Teaching Earth Sciences - Earth Science Teachers' Association

Teaching
ISSN 0957-8005
Earth Sciences
Magazine of the Earth Science Teachers’ Association
Vol 35 No 1 2010
www.esta-uk.net Registered Charity No. 1005331

Teaching Earth Sciences: Guide for Authors
The TES Editorial Team welcomes original articles on topics related to Earth science education, sent to tes.
esta@gmail.com with the author’s full name, title and address and email address.
Copy deadlines:
30 June for September publication and 31 December for March publication
Word length:
Up to approximately 2,500 words
Graphics:
• Please ensure all graphics are of a high resolution (at least 300dpi).
• It is also important to remember that images will be reproduced in black & white, so please
do not send us images where colour is important to it making sense. (For example, there is no
point using a graph with a colour key for a black & white print).
• Please do not use scanned images.
• Please send all graphics as separate files.
• Figures, tables and photographs must be captioned and referenced in the text
Scientific units:
Please use SI units throughout, except where this is inappropriate (in which case please include a
conversion table).
Format:
• Abstract of approximately 100 words (unless the article is a review)
• Appropriate headings to signpost the structure of the article
• References
References:
Please use the Harvard Referencing System. Examples below:
Articles:
Mayer, V. (1995) Using the Earth system for integrating the science curriculum. Science Education,
79(4), pp. 375-391.
Books:
McPhee, J. (1986) Rising from the Plains. New York: Fraux, Giroux & Strauss.
Copyright:
• There are no copyright restrictions on original material published in Teaching Earth Sciences if
it is required for use in the classroom or lecture room.
• Copyright material reproduced in TES by permission of other publications, rests with the
original publisher.
• Permission must be sought from the Editor to reproduce original material from Teaching Earth
Sciences in other publications and appropriate acknowledgement must be given.

Contents
From the Editor
Hazel Clark 2
From the Chair
Niki Whitburn 3
Fred Broadhurst remembered
Derek Brumhead 5
Geology and Society – ESTA Annual Course and
Conference 2010, Leicester
Gawen Jenkin 7
ESTA Conference, Southampton, 2009 9
Teaching ideas from the ‘Bring and Share’ at the Post-16 Day, ESTA
Conference, Southampton, 2009 11
Sub-surf Rocks! ESTA at Southampton
Hazel Mather 19
Climate change and sustainable development education through
the lens of Google Earth
Matthew Chilcott and Simon Haslett 20
Explosive volcanoes and the climate
Morgan Jones 24
Greenhouse to icehouse: Arctic climate change 55-33 million years
ago
Ian Harding 31
Climate change – save the planet
Ros Todhunter 36
The Tomlinson-Brown Trust: supporting the teaching of Earth
sciences
Tex Wales 38
Can the design and construction of new school and college
buildings be compatible with environmental sustainability?
Maggie Williams 40
Peneplains and plate tectonics
Mark Hayward 43
A Brief History of Oz: an Australian perspective of continental
evolution
Rick Ramsdale 48
Convoluted structural geology
Alan Richardson 52
Somerset Earth Science Centre opens
Martin Whiteley 56
Reviews 57
Diary dates 67
Teaching Earth Sciences
Teaching Earth Sciences is published biannually
by the Earth Science Teachers’ Association.
ESTA aims to encourage and support the
teaching of Earth sciences, whether as a single
subject, or as part of science or geography
courses.
Full membership is £32.00; student and retired
membership £16.00.
Registered Charity No. 1005331
Contributions to future issues of Teaching
Earth Sciences will be welcomed and should be
addressed to the Editor
Opinions and comments in this issue are
the personal views of the authors and do
not necessarily represent the views of the
Association
Designed, typeset and printed in the United
Kingdom by Hobbs the Printers Ltd, Totton,
Hampshire, SO40 3WX
Website: www.hobbs.uk.com
Editors
Hazel Clark – Editor
Mick de Pomerai – Copy Editor
Email: tes.esta@gmail.com
Advertising
Jane Hughes (retiring)
Email: tes.esta@gmail.com
Reviews Editor
Pete Loader
Email: peteloader@yahoo.co.uk
Council Officers
Chair
Niki Whitburn
Email: n.w.whitburn@bishop.ac.uk
Chair Designate
Cally Oldershaw
cally.oldershaw@btopenworld.com
Secretary
Ros Todhunter
Email: rostodhunter@aol.com
Membership Secretary
Mike Tuke
Email: miketuke@btinternet.com
Treasurer
Jane Giffould
Email: jgiffould@aol.com
Primary Co-ordinator
Tracy Atkinson
Email: tracy@kinson1.freeserve.co.uk
Secondary Co-ordinator
Chris King
Email: chris@cjhking.plus.com
Higher Education Co-ordinator
Clive Trueman
Email: trueman@noc.soton.ac.uk
Front Cover:
The danger makes
fieldwork so much more
exciting than sitting in
a nice warm lab! A sign
at Milford-on-Sea taken
on the Conference field
visit to observe the
coastal hazards.
Peter Kennett
peter.kennett@tiscali.co.uk
Do you have a photo for the cover
of our next issue?
If so, please send it in!
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences

From the Editor
Hazel Clark
I have just returned to work after the Christmas
shut down, and as usual have put on more
clothing to come inside the building! My work
colleagues are laughing, but looking somewhat
enviously at my Steptoe-like mittens and Paddington
Bear style hat!
Following on from the torrential rain during October and
November and associated floods, we are now skating
over the ice in one of the longest cold periods that I can
remember in this part of the country.
Topically, as part of its Year of Environment, Liverpool
has hosted Wild in Art’s Go Penguins http://www.
gopenguins.co.uk/site/ – a Winter’s Trail around the
city that focuses on climate change and provides hints
for ways that we can become greener. As well as the full
sized penguins, there were also schools colonies where
the decoration of each penguin was designed by the
children in association with classroom activities related to
climate change. What a fun way of getting the message
across and it has certainly been enjoyable waddling around
the Trail and interacting with the other people doing the
same thing. Perhaps the most poignant penguin was the
one decorated with two penguins standing on different
ice flows, tears rolling down their faces and the tag line
‘global warming splits up families’. Now the penguins (in
association with the Environment Agency) are advocating
recycling to reduce the impact on landfill sites. They
themselves will be recycled as they are being auctioned off
to raise funds for the Lord Mayor’s charities.
On a more serious note, it is with great sorrow that I
report the loss of Fred Broadhurst and Frank Mosely, both
renowned teachers and communicators, who had long
standing ties with the Association. An obituary for Fred has
been included in this issue and I hope to have an obituary
for Frank ready for publication later in the year.
As usual, there is a varied collection of articles for your
edification and delight such as a taster to let you know
what will be happening at the Leicester Conference and
why you will be foolish to miss it! There are several articles
related to the Southampton Conference including the ever
popular ‘Bring and Share’ and an item related to the free
CD (included with this issue) on Sub-surf rocks, plus a bit
of a theme on climate change. Then there is a mixture of
articles covering such diverse areas as building design and
environmental sustainability; peneplains and plate tectonics;
a history of Australia; convoluted structural geology and
ending up in the Somerset Earth Science Centre.
I have taken the Editorial decision to reintroduce the
geological howlers. I understand that there were some
complaints a few years ago, but I feel that we can all learn
from the misconceptions that are revealed in some of
the howlers. They are also jolly useful for filling in spaces
between articles and I would rather use something that will
make us smile than leave a blank space. I can remember
one of my school friend’s answers in a housecraft exam. The
question was “where is the hottest part of the oven and
why”. Answer “the flame – try putting your finger in it!”
Not quite the answer the teacher was looking for, but valid
none the less. So, please keep sending your howlers in.
As usual, I end with a plea. Your magazine is only as
good as the articles that you supply. Please get fingers to
keyboards and send your work to tes.esta@gmail.com.
I look forward to hearing from you soon.
Hazel Clark
Editor TES
COPY Deadlines
TES 35 2 30 June 2010 for publication in September 2010
TES 36 1 31 December 2010 for publication in March 2011

From the Chair
Niki Whitburn
Welcome to issue one of 2010. It doesn’t seem a
decade since we celebrated the new millennium and
I set off to my first GeoSciEd conference in Sydney.
Little did I realise at the time how differently this
decade might unfold for me, including changes
in direction and involvement, some fascinating
conferences and meeting so many interesting people.
Looking back at my life in the previous century it
looks quite tame, although it didn’t seem so at the
time in a challenging primary classroom.
This time I am writing as gales and floods cover the country.
Living where I do, in a hilly, wooded area, our usual
concerns are the millions of leaves covering the garden
and the hope that all the nearby trees are strong and
healthy, thus not liable to come down. However, these
concerns seem small compared to those of the residents
of Cumbria who have suffered such horrendous flooding,
described as a one in a thousand years event. This leads me
to think of all the geological links to what is happening in
Cumbria. Indeed one of the primary workshops is focussed
around rivers and erosion, and linked to underlying rocks
and soils and drainage. All this will have played a part in
the recent events, together with weather systems and the
water cycle. Indeed the events form an ideal topic for an up
to the minute investigation for schools, which could also
be linked to the human aspect with several cross curricular
links.
Once again we experienced an excellent conference at
Southampton, my personal highlight being the talk by
Iain Stewart where we were treated to extracts from his
next TV programme. It was also interesting to talk to Iain
about how his television work fits around and integrates
with his work at Plymouth University. Our thanks go to
Clive Truman for all his very hard work organising the
event for us, which I know at times was fraught with
problems, particularly when the Oceanography Centre’s
boat, Callista, was not available at fairly short notice.
His problem solving skills were much to the fore here and
resulted in delegates being able to visit the Boat Show as
an added extra. You can read more about conference
within this issue.
I recently met with Gawen Jenkin at Leicester, who is
already well ahead with the plans for conference 2010 the
theme of which is Geology and Society. Changing the Inset
workshops from Friday to Saturday had limited success
at Southampton, however the Primary and Key Stage 3/4
workshops will again be on Saturday at Leicester, with
them forming two of the strands within the programme.
Durham has been booked for 2011, for the first weekend
in July.
During conference we held our AGM at which there
were several retirements and elections. Maggie Williams
retired as Treasurer, having looked after our finances so
well for the last few years. If I needed to know anything
Maggie always had the information at her fingertips and
has guided me through many a puzzling moment. We
owe a great debt of thanks for all she has done, which
has not just involved the treasurer’s role, but many other
aspects as well. In fact we shan’t be losing her as a very
active member as she has taken on the role of Newsletter
Editor together with sponsorship liaison person relating
to our moneys from PESGB. Thank you Maggie for all you
have done and continue to do. Dawn Windley finished her
term as outgoing Chair, my thanks to her for all she did
as Chair and for her advice and help over the past year.
Jane Giffould takes over as Treasurer and Cally Oldershaw,
who was one of the previous editors of TES, has become
Chair Designate. Stephen Davies is now our display boards
manager. He would very much like to know if any of you
are attending any conferences where we are represented
(particularly ASE and the Geographical Association) and
could spare an hour to spend with our new improved
display. Jane Ladson is standing down as our Advertising
Officer and to date we still have no one to replace her.
Please consider taking on this important role, which is
quite flexible as far as timing and input. For the future,
Ros Todhunter is standing down as Secretary at the next
AGM (September 2010) so we are looking for someone to
replace her. If you would like any information about the
role please do contact her.
You will by now have received your second issue of ESTA
News, to keep you up to date between magazines. Maggie
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences

would very much like contributions for future issues,
snippets of news, outlines of courses or events, new
publications, photographs of students at work in the field,
or short items that you would like included. Please send
them to Maggie by 15th May 2010 for publication in June
2010.
Finally, I have recently been contacted by the Managing
Editor of a new European publication – Central European
Journal of Geosciences (CEJG) with an invitation for
members to submit articles for publication. More
information can be found at www.versita.com/science/
geosciences/cejg or e mail the editor Kate Cyran at
kcyran@versita.com. And don’t forget we are always
looking for articles for TES.
Niki Whitburn
ESTA Chair
Stop Press
Elizabeth Devon (a long standing member
of ESTA) has been awarded the Geological
Association’s prestigious Halstead Medal.
This medal is awarded for work of
outstanding merit, deemed to further the
objectives of the Association and to promote
Geology.
Elizabeth retired from teaching at Stonar
School, Atworth but is still very active in
promoting Earth Sciences through her
work as a facilitator with the ESEU, ESTA,
Earthlearningideas and geo-conservation in
Wiltshire.
I am sure that you will all join me in congratulating Elizabeth on this achievement.
Hazel Clark (Editor)
Your journal
needs YOU!
Wanted, enthusiastic person to co-ordinate the adverts
in Teaching Earth Sciences.
To find out what the job entails please contact
Jane Hughes via contact@esta-uk.net
Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Fred Broadhurst remembered
5 February 1928 – 1 October 2009
Frederick Munro Broadhurst, always known as Fred,
was born in Withington, Manchester, the only child of
parents May and Fred. Fred spent his childhood and
early adulthood in Burnage where he attended the
local primary school, known as The Acacias and later
in 1939, the William Hulme School.
In 1946, at the age of 18, Fred volunteered to become
a ‘Bevin Boy’ at Bradford Colliery in east Manchester.
Working underground, managing the coal trucks
transporting the coal to the surface, inspired his love of
geology (especially the Coal Measures). He decided to
further his education and (whilst working down the pit)
attended day release and night school classes at Stockport
College, studying science subjects to enable him to gain
entry to university. In 1948, with the help of the exserviceman’s
grant, he left the pit to study Geology at
Manchester University
Fred graduated in 1951 with a First Class Honours degree.
He became an Assistant Lecturer, then soon afterwards a
Lecturer, going on to gain his M.Sc. in 1953 and his Ph.D.
in 1956. Subsequently he became a Senior Lecturer, and a
supervisor for twenty PhD students.
One highlight of Fred’s career was the discovery in 1960 of
the near-complete skeleton of a 14 foot (4.3m) Plesiosaur.
The remains were found in the Alum Shales of the Upper
Lias at Ravenscar on a University field trip and caused
great excitement at the time. Later, Fred returned with
his students and spent ten days excavating the reptile.
For many years it was displayed in a large purpose-built
showcase outside the Geology Departmental library (1970-
90) and is now in the Manchester Museum.
Over thirty years ago I arranged for Fred’s rough sketch
of the plesiosaur (with baby added!) to be used on the
Manchester Geological Association membership card. It is
now the Association’s logo. At the time many knew of the
logo’s origin although unfortunately no official note was
made.
One of Fred’s many contributions was the creation of an
extraordinary network of links between adult education
classes, higher education, university research and a range
of communities throughout northwest England. Hundreds,
if not thousands, of people all over the region knew Fred
from his wonderful Workers’ Educational Association
(WEA), Manchester University Extra-Mural (later CCE) and
Wimslow Guild classes, day courses, field excursions and
visits abroad. You could not meet any person interested
in geology who did not know Fred. His passing leaves a
gap that will never be filled. He made science in general
and geology in particular both interesting and accessible.
The success of his teaching was a result of his boundless
enthusiasm for his subject, plus his patience and courtesy
in dealing with everyone he met. He had the gift of making
those with little knowledge of the subject feel just as
important as the knowledgeable ones, and nobody ever
felt left out. I spent most of my career in adult education
and I can say that Fred was the greatest adult educator I
have ever met. I have never known a person so universally
appreciated and admired. So, how appropriate that, in
2000, he should receive a national award as Adult Tutor of
the Year in North West England at the Millennium Dome in
London.
Fred also contributed greatly to the summer school held
at Bangor University which was held jointly by the WEA
and the Extra-Mural Department each year. Ian Foster and
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences

Fred worked together to deliver a weekend course there as
recently as 1996, combining their specialities as ‘Rocks and
Rails’.
In 1990, Fred retired from Manchester University to
concentrate on his work with the WEA and CCE, lecturing
at many day/evening classes and organizing foreign
geological trips with the Wilmslow Guild. With Paul Selden,
he was leader and field guide author for visits to places as
far apart as Norway, the western USA and New Zealand.
The work involved in the academic preparation and
infrastructure of each course was immense, but the huge
ability and attention to detail of both Fred and Paul ensured
some memorable trips.
Fred published over 50 articles, often in association with
other eminent geologists, in journals of international
repute. In 1982, he was awarded the prestigious John
Phillips Medal of Yorkshire Geological Society for major
contributions to our knowledge of the geology of
Northern England, and later was awarded the Silver Medal
of Liverpool Geological Society. Despite his academic
eminence, it was very easy to discuss any aspect of the
subject with him. In recent years his more general writing
brought geology to the attention of the public – the
popular 2001 book Rocky Rambles in the Peak District
(which shows his skill as an illustrator), the Guide to the
building stones of the Trafford Centre, and the recent
superb revision in 2008 of the Guide to the building stones
of Central Manchester (with Morven Simpson). This last
book, first published in 1975, was a pioneer in opening
a new field in the teaching of geology, and over the next
few years a plethora of town and city guides for the UK
appeared. The work involved in researching these guides
shows Fred at his best (along with Morven) – tracking down
architects and stone masons and discovering the names
of the often unusual rock types. Such work could involve
delicate negotiation (e.g. arranging with management for
students to be allowed to crawl around the floors of the
Trafford Centre!) something that Fred was excellent at.
I first met Fred forty years ago leading a geological trail
walk in Lyme Park. Over the succeeding years we met many
times and I benefited so much from his knowledge and
expertise imparted with much generosity; always up to
date, of course, with the latest developments and theories,
and this continued into his ‘retirement’. The last walk
that I went with him was with the MGA group at Styal in
July 2009. It lasted an hour and a half, with Fred going at
his usual 150mph. At the end when we were all looking
forward to a cup of tea, Fred said he must be off to take a
second group around. What more can one say?
He had a lovely sense of humour. My favourite example
was when we were in Dublin, thirty years ago, with the
Palaeontological Association. We came across a bus stop
sign which said – ‘The following buses do not stop here’.
We both fell about laughing and each took a photograph.
No doubt his will still be there among the many thousand
others. What a treasure trove there must be amongst
those?
It’s only a few months ago since we were emailing each
other about re-arranging his talk to the New Mills Local
History Society (‘New Mills 300 million years ago’!) and
getting down to finishing a trail on the Torrs gorge. It
is shocking that such a seemingly indestructible person
should be taken so quickly in this way. When we lose
someone like Fred, it reminds us all of our own mortality.
Despite his enormous commitments, Fred was a wonderful
family man. Having met Rosemary at a University Union
dance, they married in 1958, and had two children Andy
and Caroline. Now, there are also four grandchildren.
Fred took great delight in his children and grandchildren
and had a fantastic relationship with them. His love of
mountains and walking in the Peak District was passed on
to the family and the walks continued until summer of this
year when Fred started to feel poorly.
At the beautifully simple funeral ceremony, his
grandchildren each gave a moving appreciation of their
‘inspirational’ grandfather. His presence will be missed but
the ‘Fred Effect’ will pass on for generations to come.
Derek Brumhead
Manchester Geological Association
DDB@tesco.net
Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Geology and Society –
ESTA Annual Course and Conference,
Leicester 2010
A wet, grey Wednesday afternoon in December. The
Copenhagen summit looks likely to end in deadlock,
or worse an impotent compromise, and I’m still
thinking about Attenborough’s Horizon programme
last week on world population. Is it our fault the state
that the planet is in? After all, geologists found all
the hydrocarbons and made it possible to combust
them in such quantities! And we sustained economic
and population growth by meeting the challenge of
providing more, and cheaper, natural resources – from
copper to extend electricity supply, tantalum for every
mobile phone, to cement and bricks for new houses!
Or, were geologists just responding to the needs of
society? And in fact are we not the potential saviours
of humanity – heroes that told everyone that climate
change was possible – and, furthermore, can actually
do something about it (with carbon sequestration,
and more controversially nuclear energy)? May you
live in interesting times…!
such as methane hydrates will all be explained by experts in
the field.
Perhaps the future of the human race lies in the stars
– or at least nearby planets – so we will have planetary
geologists talking about recent research on the geology of
Mars. The practical application of geology, in a more down
to Earth sense – solving crime – will be examined by two
keynote speakers on forensic geology. Dr Laurance Donnelly
(Wardell-Armstrong) is a geologist who has collaborated
with a number of police forces in their investigations,
and for 11 years, has applied geological capabilities and
expertise to search for buried murder victims. Dr Jane
Evans, (Head of Science-based Archaeology, NERC Isotope
Geosciences Laboratory) will show how an understanding
of bedrock geology, and its isotopic composition, can
The manifold interactions of the geology of spaceship
Earth with the people who live on it are explored in the
theme of this year’s ESTA annual conference at Leicester:
‘Geology and Society’. It is after all the human-angle that
really engages many of our students – ‘Will that volcano
erupt? Can we safely build there? Can we provide water
for this village?’ This theme we hope embodies many of
the forward-looking (and ultimately optimistic!) areas of
applied research taking place in the Leicester department,
whilst not neglecting more traditional geology.
Whilst details of the programme are still being arranged,
here is a taster of what we plan to offer:
Dr Jan Zalasiewicz, author of ‘The Earth After Us’, will
discuss whether, as a result of the effects of human
activity on the global environment, we are entering a new
Geological Era – the Anthropocene. Complementing this,
Prof. Mike Petterson will discuss sustainable development
and how geology can be a force for good in delivering
economic benefits to developing countries. Examining
carbon in particular, the carbon cycle, recent climate
change, geological carbon sequestration and novel fuels
The National Space Centre, Leicester. © Leicester Shire Promotions Ltd.
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences

Jane – a 6.4 metres long sub-adult Tyrannosaurus rex skeleton, part of the Flying
Dinosaurs and origin of birds display in the Leicester Geology Department.
Photography by Design Services, ©University of Leicester.
be used to trace the origins and migration of human
communities – as well as modern murder victims.
Of course geology is not just of practical use;
comprehending the vastness of Earth history gives us
geologists a unique perspective on how we relate to the
planet and the incredible story of the evolution of life.
To remind us of the beauty and grandeur of life on Earth
Prof. David Siveter will present a special evening lecture
on exceptionally preserved fossils including the ornate
3-dimensionally-preserved species from the Herefordshire
Lagerstätte.
Talks will form just part of the conference, with plenty of
opportunities for hands-on action in workshops, INSET
courses (for Primary, KS3/4, Post-16 and HE), and fieldwork
on the Sunday. Workshop subjects planned include remote
sensing and GIS, comets and meteorites, reconstructing
diet from vertebrate skulls, and ocean drilling – to name
just a few! Field trip options are planned to include
Charnwood Forest – home to Charnia – the oldest
macrofossils in the UK, the fossil-packed Jurassic rocks to
the east, hands-on shallow geophysics, a visit to a major
quarry operation, or a tour of rock sculptures (geology and
art!) in the beautiful university Botanic Gardens.
Tungsten carbide drill head – entrance foyer, Leicester Geology Department.
Photography by Design Services, ©University of Leicester.
And if all that isn’t enough to whet your appetite there will
be plenty of opportunities to socialise, both day and night.
We are currently seeking generous sponsorship of the
conference from industry and are delighted to announce
that we plan to hold the conference dinner at the award
winning National Space Centre visitor and educational
centre. As well as a dinner within the Planets gallery,
the evening will include a drinks reception in the Rocket
Tower, space simulator rides, a 360° film show in the Space
Theatre and free access to all the galleries including the
Earth from Space, the Planets, and Exploring the Universe.
From the mantle to outer space, from the first fossils to the
Anthropocene – we hope ESTA 2010 will have something
for everyone!
Dr Gawen Jenkin
Department of Geology, University of Leicester.
The ESTA Annual Course and Conference will be
hosted by the University of Leicester on the 17th-
19th September 2010. Leicester is centrally located in
the UK and easily reached by train, bus, road and air.
The Geology Department is home to a pet dinosaur
called Jane. Further details of the conference will
be posted on the ESTA website http://www.estauk.net/leicester%20conference.html
or for further
information contact Gawen Jenkin,
geology@le.ac.uk.
"Pillow lavas were formed when the shelly
limestone hardened"
Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

ESTA Conference,
Southampton 2009
Photos by Peter Kennett
Figure 1 The R.V.Bill Conway is dwarfed by the cruise liner moored nearby
Figure 4 Marine organisms in very smelly mud
Figure 2 Dredging in the Southampton Water
Figure 5 A strict dress code is required in the halls of residence
Figure 3 Investigating the contents of the dredge
Figure 6 Ian West describes the coastal processes around Milford-on-Sea
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences

Figure 7 Ros Todhunter makes presentation to Clive Trueman at the celebration dinner for organising such a splendid conference
Figure 8 Cliff erosion at Barton-on-Sea
Figure 9 Intrepid geologists face danger in search of answers
10 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Teaching Ideas from the ‘Bring and
Share’ at the Post-16 Day, ESTA
Conference, Southampton, 2009
The ‘Bring and Share’ session at the ESTA Conference in Southampton in 2009 was as well supported and popular
as ever, with many splendid contributions. We are very grateful for all the contributions and particularly to those
people willing to ‘go the extra mile’ of writing them up (shown by asterisks). They were wide-ranging, thoughtful
and fun. Read on to find out more.
• *Paul Grant ‘A tea towel Isle of Wight monocline’
• Dave Rowley, Wells Cathedral School, Wells: ‘Reading list’
• *Chris Bedford, Radley College, Abingdon: ‘Radiometric dating made simple’
• *Peter Kennett, Chris King and Elizabeth Devon ‘Earthlearningidea – one year on’
• **Elizabeth Devon: ‘Impact calculator’ and ‘Make your own spectroscope’
• Mike Tuke, ESTA: ‘Faulting and outcrop patterns’
• ***Pete Loader, St Bedes College, Manchester: ‘Stable slopes – another angle’, ‘Death assemblages in a
nutshell’ and ‘A chip off the old block – in 3D’
• Dawn Windley, Thomas Rotherham College, Rotherham: ‘Geological Family Fortunes’
• *Dave Turner, Matlock High School: ‘Papier-mâché palaeo’
• Abigail Brown, Hagley Catholic High School, Hagley: ‘Drag and drop’
• Rebecca Gould, Scarborough Sixth Form College: ‘What do you want?’
• *William Lynn and Nichole Sloan, Oakgrove College: ‘Fossil revision cards – updated’
• *The Geological Society: ‘Speakers list’
• *Chris King, Keele University: ‘New GCSE geology textbook, The planet we live on – the beginnings of the
Earth Sciences’
Could the post-16 ‘bring and share at Leicester 2010 be even better than this? Do come and find out, and please bring your
own ‘bring and share’ ideas. With your contributions, another dynamic and uplifting session is in prospect.
Chris King.
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 11

Idea Title:
Presenter:
Brief description:
A tea towel Isle of Wight monocline
Paul Grant, ESEU Facilitator, eseu@keele.ac.uk
A table cloth or carpet is commonly used to illustrate how horizontal compression causes folding, at a
range of educational levels. This demonstrates fold shortening of the Earth’s crust.
However, if a pre-existing weakness occurs, deformational strain may well be concentrated along
these weaknesses, and this can also be demonstrated using a tea towel instead of the table cloth /
carpet. The line of weakness is induced by ironing a sharp crease into the tea towel.
Put the tea towel onto a table top with the ironed crease facing downwards, then ‘compress’ the tea
towel to produce marginal folds (equivalent to the Alps – see below) and, at a distance a fold – which
may be geometrically equivalent to the Isle of Wight monocline (see photos).
A good example of this style of deformation is the Wessex-Weald sedimentary basins, which were
formed as a consequence of crustal thinning generating normal fault zones with an approximately
E-W strike. These are the zones of weakness. Alpine compression as a result of the collision of Africa
and Europe caused intense deformation at the plate margins, but strain was also transmitted long
distances across Europe resulting in the open fold of the Weald and Thames Basin. The zones of
concentrated deformation are exemplified by the Isle of Wight Monoclinal system, formed as shown
in the photographs. See, Hillis R.R. et al (2008) Cenozoic exhumation of the southern British Isles.
Geology 36, 371-374 for a more detailed explanation.
The tea towel before deformation
by stresses from left and right
The ‘Isle of Wight Monocline’
formed between ‘Europe’ and ‘Africa’
If the tea towel is placed with the ironed crease facing upwards, then ‘compressing’ the tea towel
produces marginal folds again and, at a distance, a sharp up-lift – comparable to the structures above
blind thrusts.
Age range:
Apparatus/
materials needed:
KS4 and older
Tea towel
12 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Idea Title:
Presenter:
Brief description:
Radiometric dating made simple
Chris Bedford, Radley College, OX14 2HR, cmb@radley.org.uk
Different coloured chocolates (see apparatus list) are used to show the following:
• changing parent:daughter ratios as radioactive decay proceeds
• effect of loss or gain of daughter or parent isotope and potential errors caused
Age range: 16+
Start with (say) sixteen chocolates of one colour – this represents the number of parent atoms at time
zero. One by one, replace with different coloured chocolates (daughter atoms) until half of the original
number have been replaced. One half-life has now passed. Continue for another two or three
half-lives. Discuss the changing ratio of parent to daughter atoms as decay proceeds. One could start
again with a different number of parent atoms (chocolates) to show that it is the parent:daughter
ratio that is important, not the original number of atoms.
Now investigate the possible errors caused by loss or gain of parent or daughter chocolates. The most
obvious is to remove (eat) some or all of the daughter chocolates (eg. loss of daughter argon due
to weathering or metamorphism) after some have had time to accumulate. Discuss the new parent:
daughter ratio and what the age appears to be. Various other scenarios can also be modelled, e.g.
daughter chocolates present to begin with (presence of non-radiogenic daughter atoms in the rock),
addition of parent chocolates during decay (hydrothermal addition of parent potassium), etc.
Apparatus/
materials needed:
One packet of Milkybar moments (white)
One packet of Galaxy Minstrels (brown)
(though any sweets of two different colours are of course possible)
Idea Title:
Presenter:
Brief description:
Age range:
Apparatus/
materials needed:
New GCSE geology book, ‘The planet we live on – the beginnings of the Earth sciences’
from: http://www.learndev.org/ScienceWorkBooks.html
Chris King, Keele University, chris@cjhking.plus.com
A new geology textbook is available free online from the web address above. It is Book six in the
‘Basic books in science’ series, written particularly for students in developing countries who have no
access to printed materials. It has been written to the new GCSE Geology specification (WJEC), to
double as a GCSE geology textbook, with the same format as the geology specification of:
• Reading rock exposures: how rock exposures contain evidence of how they were formed and
subsequently deformed
• Reading landscapes: how landscapes contain evidence of the relationship between past and present
processes and the underlying geology
• Understanding the ‘big ideas’: major concepts that underpin our current understanding of the
Earth
• Fitting the major geological events that have affected the Earth into a timeline
• Understanding the importance of current geological events, as commonly reported in the media
• Understanding what geologists do: how geologists use investigational skills in their work today
14 upwards
The downloaded pdf file of the book from the website
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 13

Idea Title:
Presenter:
Brief description:
Earthlearningidea one year on
Peter Kennett, Chris King and Elizabeth Devon, Earthlearningidea, info@earthlearningidea.com
http://www.earthlearningidea.com is a voluntary website, which is continuing to provide simple
ideas for Earth science teaching with limited equipment, and which has now reached over 145 countries.
The following activities from the website were demonstrated:
Craters on the Moon – why are the Moon’s craters such different shapes and sizes?
Darwin’s big coral atoll idea – try thinking like Darwin did to solve the coral atoll mystery.
The format of the activities was shown through a live web link, and exemplified by the activity:
Trail-making – make your own “fossil” animal trails, featuring an ESTA member in a compromising
position!
Age range:
Apparatus/
materials needed:
Top Primary to Secondary
a) sand tray, cocoa powder, sifter, ball bearings of various sizes, ruler or tape measure, catapult (optional!).
b) simple model – two sheets of A4 paper and some sticky tape: deluxe model – fabric, wire, needle
and thread, small fish tank, water
c) access to data projector with live web link.
Idea Title:
Presenter:
Brief description:
Impact calculator, found at: http://down2earth.eu/impact_calculator
Elizabeth Devon, Earthlearningidea, info@earthlearningidea.com
Choose asteroid diameter, trajectory angle, object velocity, projectile density, target density and then
choose your target. You can see the crater size, crater depth and assess impact energy data.
Age range: 10 – 100
Apparatus/
materials needed:
Access to the internet
Idea Title:
Presenter:
Brief description:
Age range:
Apparatus/
materials needed:
Make your own spectroscope, as shown at: http://www.cs.cmu.edu/~zhuxj/astro/
html/spectrometer.html
Elizabeth Devon, Earthlearningidea, info@earthlearningidea.com
Using a cardboard cut-out and a small piece from an old CD, pupils can make their own spectroscopes
10 – 14 years
Cardboard cereal box
Old CD
14 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Idea Title:
Presenter:
Brief description:
Stable slopes – another angle
Pete Loader, St Bedes College, Manchester, peteloader@yahoo.co.uk
An old, clear plastic CD case with the internal moulding removed is marked on the outside with a
selection of appropriate slope angles (e.g. 30˚, 40˚, 60˚ etc) with a permanent marker pen. The empty
CD case is part-filled (trial and error) with dry sand. Children’s “playsand” works well but can be
adapted to investigate stable slope angles in other fine materials (shape, size sorting of grains). The
CD is tilted to the vertical and the sand finds its own stable angle (~32˚). This is useful in the classroom
and in the field for demonstration
The CD case before tilting …
…. and after
Age range:
Apparatus/
materials needed:
All
An empty clear CD case with inner moulding removed.
Dry sand (Children’s play sand is good)
Sellotape and/or sealer
Permanent marker pen for writing on plastic case.
Idea Title:
Presenter:
Brief description:
Age range:
Apparatus/
materials needed:
Papier-mâché palaeo
Dave Turner, Highfields School, Matlock.
Dave showed how his students had made mega models of macro fossils as teaching aids using the
resources of his friendly school art department.
Any
Chicken wire
PVA or cellulose glue
Newspaper
Paint
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 15

Idea Title:
Presenter:
Brief description:
Death Assemblages – in a nutshell
Pete Loader, St Bedes College, Manchester, peteloader@yahoo.co.uk
The shells of pistachio nuts are used as an analogue for bivalve shells. When randomly dropped into
a bowl of water they nearly always orientate with the concave part of the shell facing upwards (the
shell providing least resistance to the water in this direction (see photo). When the water is then
stirred the shells generally flip over to show a typical transported “death” assemblage identified in
some shelly limestones. This works well as a laboratory coursework investigation and simple statistics
can be easily obtained by counting with the significance of the results evaluated against probability.
This works well if around 25 shells are used in a standard kitchen mixing bowl (or equivalent). If more
are used (greater density) the shells often interfere with each other and form an imbrication also seen
in some limestones (photo).
Nutshell ‘bivalves’ after dropping into water
‘Imbricated’ nutshell ‘bivalves’
Age range:
Apparatus/
materials needed:
All
A bag of pistachio nuts
Bowl (or equivalent)
Water
A good film to watch whilst shelling (and eating) the nuts
Idea Title:
Presenters:
Brief description:
Age range:
Apparatus/
materials needed:
Fossil revision cards – updated
William Lynn, Foyle and Londonderry College, and Nicole Sloane, Oakgrove Integrated College,
Northern Ireland, roc_chic_nic@hotmail.com
This unique collection of 24 A6 revision cards for the four AS and A2 modules has been updated.
It describes the morphology, evolutionary changes, description and function of body parts for the
main invertebrate fossil groups and plants including Ammonites; Belemnites; Bivalves; Brachiopods;
Crinoids; Corals; Echinoids, Gastropods; Graptolites; Trilobites. Many schools are currently using sets
of these purchased for their students and are finding them invaluable.
A-Level
None – other than the cards. Please contact the authors for more details.
16 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Idea Title:
Presenter:
Brief description:
A chip off the old block – in 3D, from http://geology.isu.edu/topo/blocks/
Pete Loader, St Bedes College, Manchester, peteloader@yahoo.co.uk
This is an excellent website and a must for all attempting to show geological mapwork structures in
3D. GeoBlocks 3D contains interactive QuickTime Virtual Reality (QTVR) movies exploring the three-dimensional
nature of geology, specifically geologic structures within blocks. It was created by Stephen
J. Reynolds, Debra E. Leedy, and Julia K. Johnson, Arizona State University. You can rotate the blocks,
make them partially transparent to view their internal structure, cut through or erode them, displace
faults, and more. It is excellent and it also comes with downloadable exercises and worksheets!
Example: Transparent folds and faults
Worksheet example
Age range:
Apparatus/
materials needed:
All – particularly GCSE to A2
Computer
Web address – http://geology.isu.edu/topo/blocks/
Idea Title:
Speakers list from: http://www.geolsoc.org.uk/gsl/education/schools/page5537.html
Presenter:
Brief description:
Age range:
Apparatus/
materials needed:
The Geological Society
The Society publishes a list of speakers willing and keen to visit local schools to make presentations to
students about geology on a range of topics. The seven page list can be downloaded from the web
address above.
14 upwards
The list from the web address above
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 17

18 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Sub-surf Rocks! ESTA at Southampton
Hazel Mather
Sub-surf Rocks! is a new, free online resource aimed at
enhancing A-level geology teaching using seismic data.
It was produced by the charity UKOGL (UK Onshore
Geophysical Library) using datasets from its public
domain UK onshore seismic data archive. The website
www.sub-surfrocks.co.uk has been loaded to CD-
ROM and a copy is included with this issue of TES.
The resource was developed with help from members
of ESTA and is designed to relate to A-level geology
teaching requirements. At the launch in Southampton,
delegates were given a brief tour of the website which
supplies information in short sections and uses audio-visual
presentations and animations. Topics include:- background
information on seismic exploration; how seismic data
are acquired; how to interpret seismic data; a glossary of
keywords used in the text; some embedded mathematics
and a quiz. A case study of the hydrocarbon-producing
Weald Basin contains a ready-to-use student exercise and
features a 3-D model provided by the British Geological
Survey illustrating the relationships between the solid
geology, geological cross-section and seismic data.
Those at the session were then let loose with coloured
pencils and a copy of the seismic line (downloadable as A3
or A4 colour or greyscale printable files from the CD
or website) and invited to ‘find the oil’ for themselves.
The exercise requires the interpretation of three horizons
and the picking of several faults. Many delegates
commented on the excellent quality of the data
which clearly depicts the structural features. There is
a stratigraphical column to complete and questions
encouraging students to identify source, reservoir and
cap rocks before finally picking a location to drill.
A PowerPoint presentation with ‘the answer’ finished
off the session, although as is often the case with
interpretation, there may not be a definitive answer
giving scope for interesting extension activities.
UKOGL has also made available PDF images of all the
seismic lines in its library. Seismic coverage of the UK is
pretty good and so it may be possible for you to download
an image of subsurface under your school or town. See
the UKOGL website at www.ukogl.org.uk for free
downloads.
Finally I apologise for the title, it was irresistible!
Hazel Mather
pink.house@virgin.net
'technology and transport has improved so
much in recent years that the coal mines are
now located away from the coalfields'
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 19

Climate change and sustainable
development education through the
lens of Google Earth
Matthew Chilcott and Simon K. Haslett
Abstract
Climate change impacts and sustainable development
issues span many spaces and scales, from individual
homes through to local communities, regions, nations
and beyond, but requiring of students to appreciate
these diverse contexts is challenging. Google Earth
is a software package that may be downloaded free
of charge from the internet and provides continuous
global satellite imagery. It has the potential to
offer opportunities for educators to embed world
sustainability themes within the curricula of almost
any subject. The Sands of Time – A Google Earth
Approach to Climate Change Education e-publication
provides a case study that employs Google Earth in
examining climate change impacts and sustainable
development issues in North Africa. This article shows
how educators can make use of the same tool in
engaging students with digital technology in climate
change and sustainable development education.
Introduction
Google Earth offers educators and the public a new
and engaging method of exploring and learning about
the World. It is a virtual globe, map and a Geographical
Information System (GIS). It maps the earth by the
superimposition of images obtained from satellite imagery,
aerial photography and GIS 3D globe. It has proved
popular as a tool, with its easy to use simple navigation
features, and the ability to integrate other forms of internet
published content such as photographs from Panoramio
and video sequences from Youtube. As a consequence of
its widespread use, Google Earth offers the opportunity
for knowledge transfer and inclusion of the World’s
community in exploring climate change through a visually
stimulating and interactive medium. The potential for its
use across curriculum areas may yet to be fully utilised
and as educators seek engaging ways of offering students
increased levels of technology enhanced learning it is
possible to predict its increasing use across disciplines.
Academic research that employs Google Earth spans a
number of disciplines, including archaeology, biodiversity,
earth sciences, geography, health, planning, tourism, urban
development and water technology. Although Google Earth
launched its Outreach programme in 2007, its use in Higher
Education (HE) as a learning resource to support global
issues education has not been extensively documented in
the literature, but is beginning to be evaluated in the earth
sciences (e.g. Haslett, 2009a; Thorndycraft et al., 2009).
The functionality of Google Earth has enabled the
development of large budget digital media productions
that utilise Google Earth’s integrated application layers to
tell stories and reveal the human impact on the landscape.
These developments help contextualize climate change
issues for global audiences and seek to widen access and
participation of the world’s citizens in contributing to
reducing carbon emissions. These are excellent resources
that seek to engage with a broad breadth of users and
delivery contexts from the public, policy makers, scientists
to the classroom. Arguably, however, the broad approach
these take loose a sense of the ‘local’ case study that
contextualizes climate change impact on place and time in
many traditional educational contexts.
Against this backdrop it remains highly pertinent for
other educators to use Google Earth to raise awareness
of climate change impacts in location specific contexts.
This is particularly evident when considering arid and
desert climates where the impact of climate change can be
tracked and investigated using the core satellite image data
in Google Earth.
For example, the use of Google Earth in sustainable
development in business and industry is beginning to
gather pace. Indeed, the Google Earth website highlights
the growing application of the technology to industry
and business, with relevance to employment areas in
commercial and residential real estate, architecture
and engineering, insurance, media, public and nongovernmental
organizations, national and local
government, and defence, security and intelligence.
Embedding sustainable development through the use of
Google Earth provides an exciting opportunity to raise
student awareness in global sustainability issues and
exposes them to useful employability skills.
20 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Potential exists to use Google Earth in a virtual learning
environment, in a conventional classroom, or laboratory or
field setting, whether in supervised groups or self-directed,
and may be applied in almost any subject area studied at
HE Institutions. At the University of Wales, Newport, we
have developed an e-publication entitled The Sands of
Time: A Google Earth Approach to Climate Change
Education (Haslett & Savage, 2009) that can be argued to
have broad relevance. The e-publication clearly has the
potential to support student outreach programmes and offcampus
activities, such as expeditions and voluntary
placements. It is hoped that this research will help to
promote Google Earth in the University portfolio of online
learning resources in the UK and abroad. The e-publication
(Haslett & Savage, 2009) is tailored directly for educators
and reports on a sustainable development and climate
change case study developed as part of a Higher Education
Academy-Geography, Earth and Environmental Sciences
Subject Centre Funded Project. It includes an introduction
to climate change, a detailed case study and an educational
exercise all of which are available for free educational use.
The publication can be accessed directly from
http://idl.newport.ac.uk/celt/sandsoftime. The
resource has been produced using the Adobe Flash
creative authoring tool and incorporates Digital Earth
video sequences created using the Google Earth Pro video
capturing tool. This was added to with wider free to use
educational contextual video sequences obtained from
the Open2.Net creative archive. The publication has been
produced with an intuitive design which includes an inbuilt
navigation function to enhance accessibility. This enables
users of the publication to explore the materials using
the arrow keys on computer keyboards in addition to
navigating via chapter headings.
Google Earth Case Study – Climate Change and North
Africa.
Haslett & Savage (2009) present a case study of climate
change impacts in western North Africa that can be
investigated through a blended learning approach using
Google Earth. The case study originated from palaeoclimate
research undertaken on deep-sea cores collected by the
Ocean Drilling Program (ODP) offshore Cap Blanc on the
coast of Mauritania (Haslett & Davies, 2006). The data
has contributed to the development of a blended learning
exercise that attempts to encourage learners to evaluate
the past in order to understand the present (Haslett,
2009b). The main conclusion from the palaeoclimatic
data is that warmer Atlantic sea-surface temperatures
(SSTs) have promoted, in the past, increased North African
aridification. Armed with this theory, students are then
able to view atmospheric and SST records since the early
20th century and relate this to episodes of North African
aridity. Moreover, in relation to Mauritania, students can
chart the urban development of Nouakchott, the capital
city of Mauritania (located on the coast close to Cap
Blanc) (Chenal & Kaufmann, 2008), which itself appears
to correspond to local cycles and aridity and, therefore,
climate change.
Figure 1 Haslett, S.K., Savage, N. (2009) The Sands of Time: A Google Earth Approach to Climate Change Education. Newport: University of Wales. Available from http://idl.
newport.ac.uk/celt/sandsoftime/ (accessed 18th December 2009).
• Figure 1 is provided with the University of Wales, Newport’s endorsement for use in the publication.
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 21

Figure 2 NASA Earth Observatory (2006) Satellite image of Nouakchott, Mauritania, showing sand dunes threatening to take over the city.
Available from: http://earthobservatory.nasa.gov/IOTD/view.php?id=6234 (accessed 22nd December 2009).
• Figure 2 has been sourced from the NASA Earth Laboratory and is provided with a creative commons licence referenced here:
http://commons.wikimedia.org/wiki/File:Nouakchott_L7_20010109_lrg.jpg
Google Earth can be employed to examine the city of
Nouakchott and its eastern border with the Sahara
Desert. It is clear from Google Earth images that desert
sands are encroaching into the streets of Nouakchott
suburbs, leading to the abandonment of some buildings.
Google Earth images also reveal that further to the east,
environmental management practices are being deployed
to arrest the westward migration of the desert dunes,
including the planting of vegetation on the stoss side
of dunes, and the construction of a gridwork of fences
to trap and stabilise moving sand fields. Jensen & Hajej
(2001) document these management practices in relation
to preventing dunes blocking roadways in Mauritania,
but the same techniques are being used to reduce sand
inundation of the city itself. This technique of constructing
a ‘green belt’ around the city is becoming a widespread
practice in North Africa, where they are also referred to
as Green Necklaces and Green Walls (CEN-SAD, 2008).
Google Earth can be used to examine these features and
using the oblique view facility it is possible to clearly place
these within the geomorphological context of the desert
landscape. This case study demonstrates the valuable
contribution that Google Earth can make to student
learning as part of a blended learning approach, where
Google Earth exercises are complimented by data exercises
and research literature.
22 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Conclusion
Since the development of The Sands of Time e-publication
Google have developed their own series of Climate
Change Tours that are available for educators to utilise
within the Google Earth platform. Working in partnership
with Climate Change leaders, including Al Gore and
Steve Schneider, alongside Greenpeace and the World
Wildlife Fund an increasing number of climate change
tours are available from their Climate Change in Google
Earth website (Google Earth, 2009). In the UK, the
Meteorological (MET) Office in collaboration with the
Hadley Centre and other agencies have also utilised Google
Earth to educate about the impact of Climate Change
with a focus on temperature change and greenhouse gas
emission scenarios (MET Office, 2008).
In consideration of the fast evolving nature of the web
based applications the work of Goodchild (2007) is worthy
of continued review in relation to the accommodation of
broad and distinct audiences and connections between
problems and objectives for digital earth applications and
the potential for ‘virtual collaboratories’ for educators to
produce shared content for digital earth platforms.
Whilst the use of Google Earth and other online tools
provides educators with a wealth of opportunities to enrich
the student experience of sustainable development and
climate change education across subject areas it is worthy
of reflection that the Joint Information Systems Committee
in their recent Green Information Communication
Technology (ICT) briefing paper (JISC, 2009) highlight the
estimate that the global use of ICT accounts for 2% of all
carbon dioxide emissions. In the case of UK further and
higher education institutions 500,000 tonnes of carbon
dioxide emissions are estimated to be produced through
the use of ICT on an annual basis. As the teaching of this
curriculum area embraces relevant online platforms too
there is a need to also consider the carbon footprint of
such activity in an ever increasingly digital world.
References
CEN-SAD (2008) The Green Wall initiative for the Sahara and the Sahel.
Tunis: Sahara and Sahel Observatory, Introductory Note No. 3, 44pp.
Chenal, J. & Kaufmann, V. (2008) Nouakchott. Cities, 25, 163–175.
Goodchild, M. (2007) Citizens as sensors: the world of volunteered
geography. GeoJournal, 69, 211-221.
Google Earth (2009) Climate Change in Google Earth Available from:
http://www.google.com/landing/cop15/ (accessed 14th December
2009)
Haslett, S. K. (2009a) Prior use of Google Earth by undergraduate
Geography students. Planet (HEA-GEES Subject Centre Journal), No. 22,
43-47.
Haslett, S. (2009b) Unravelling the then and there to understand the
here and now: relevance of palaeoclimatology to climate change
education. In Climate Change: Global Risks, Challenges and Decisions.
IOP Conference Series: Earth and Environmental Science, 6,
doi:10.1088/1755-1307/6/7/072026.
Haslett, S. K. & Davies, C. F. C. (2006) Late Quaternary climate-ocean
changes in western North Africa: offshore geochemical evidence.
Transactions of the Institute of British Geographers, NS 31 (1), 34-52.
Haslett, S. K. & Savage, N. (2009) The Sands of Time: A Google Earth
Approach to Climate Change Education. Newport: University of Wales.
Available from http://idl.newport.ac.uk/celt/sandsoftime/ (accessed
18th December 2009).
Jensen, A. M. & Hajej, M. S. (2001) The Road of Hope: control of moving
sand dunes in Mauritania. Unasylva, 52, 31-36.
JISC Briefing Paper (2009) Green ICT Managing sustainable ICT in
education and research. Available from http://www.jisc.ac.uk/media/
documents/publications/bpgreenictv1.pdf (accessed 14th December
2009)
MET Office (2008) Climate Change in Google Earth. Available from
http://www.metoffice.gov.uk/climatechange/guide/keyfacts/
google.html (accessed 14th December 2009)
Thorndycraft, V. R., Thompson, D. & Tomlinson, E. (2009) Google Earth,
virtual fieldwork and quantitative methods in Physical Geography. Planet
(HEA-GEES Subject Centre Journal), No. 22, 48-51.
Matthew Chilcott
Institute of Digital Learning, University of Wales, Newport,
Allt-yr-yn Avenue, Newport, NP20 5DA, UK.
Matthew.Chilcott@newport.ac.uk
Simon K. Haslett
Centre for Excellence in Learning and Teaching, University
of Wales, Newport, Lodge Road, Caerleon, NP18 3QT, UK.
Simon.Haslett@newport.ac.uk
Choice of section X, Y or Z
– candidate choice = "A"!
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 23

Explosive volcanoes and the climate
Morgan Jones
Introduction
Volcanic eruptions, an awe inspiring testament
to the power of Nature, have rightly taken their
place alongside such heavyweights as Dinosaurs in
enthusing younger generations to take an active
interest in Earth Science. However, due to the sporadic
and infrequent nature of eruptions, there are still
gaps in scientific understanding of the causes and
effects of such phenomena. An emerging field of
study is the influence that volcanoes exert on the
climate. Effects associated with volcanic eruptions
have been shown to have an adverse effect on the
climate system over a period of days to decades. As
eruptions are infrequent and large eruptions even
more so, we still know little about the nuances of
these climatic effects. While this field of scientific
study has made great strides forward, the lack of
observational evidence available means there are
still gaps in our understanding. In this article, I will
summarise what we currently know about volcanic
eruptions, and then focus on how the atmosphere,
oceans, and terrestrial environments are affected by
these events.
Explosive Eruption Dynamics
When high viscosity magmas move towards the surface,
the volatiles in the magma start to form bubbles that
cannot easily escape. If the rate of ascent is also high, then
the internal pressure of these bubbles eventually exceeds
the viscous relaxation rate of the melt, rupturing the films
between bubbles and causes the magma to disintegrate
in a brittle fashion. The upwards flow of the mixture is
suddenly changed from being dependent on the viscous
properties of the magma (~ 10 7 Pascal seconds) to that
of the inertial forces of the gas phase (10 -5 Pa s). It is this
huge 12 order of magnitude jump in dynamic viscosity
that propels the disintegrating mass out of the vent close
to the speed of sound (Woods & Wohletz, 1991). A good
historical example of such an eruption is the 1991 eruption
of Pinatubo, Philippines.
The rapid injection of the gas-particle mixture into the
atmosphere leads to significant entrainment of the
surrounding air. The air is heated, expands and dilutes
the solid component of the erupted material, which
significantly reduces the eruption column density and
gives the jet buoyancy. This is countered by initial negative
buoyancy and the transference of momentum to the
surrounding air. Sufficient entrainment of air allows part of
the eruption column to become buoyant and rise through
the atmosphere (Sparks et al., 1986). The rising mass of
material forms an umbrella cloud when it reaches neutral
buoyancy, which has been estimated to be between 27
and 38 km above sea level for larger eruptions (Woods &
Wohletz, 1991) (Figure 1). The high intensity of explosive
eruptions and the fine particle size allow tephra to remain
airborne for days, capable of travelling over 3000 km
from the source prior to deposition in extreme cases
(Oppenheimer, 2002).
Eruption size and frequency
Explosive volcanic eruptions can be extremely large. The
standard way of expressing the size of a large eruption
is using the volume of pre-erupted magma that is
subsequently evacuated, termed the Dense Rock Equivalent
(DRE). To give an idea of scale, the 1980 eruption of Mount
St. Helens (USA) erupted about 1 km 3 DRE magma, while
the largest known historical eruption, the 1815 eruption
of Tambora (Indonesia), is estimated to have erupted 30 to
50 km 3 DRE of magma (Self et al., 2004). Explosive supereruptions,
a term made famous by the BBC docudrama on
Yellowstone (USA), are now defined as eruptions with preerupted
volumes in excess of 400 km 3 . This is equivalent
to an erupted mass of 10 15 kg. The largest super-eruption
deposits discovered in the geological record are predicted
to have been over 100 times larger than Tambora (1000’s
of km 3 DRE), dwarfing anything witnessed in historical
times.
These super-eruptions are extremely rare events so it is very
difficult to evaluate their occurrence globally, regionally,
or for an individual volcano (Coles & Sparks, 2006). The
average global repose period for super-eruptions exceeding
1000 km 3 DRE magma, based on geological evidence, is
0.3 to 1 Million years (Mason et al., 2004; Self, 2006).
However, large magnitude volcanism is episodic in nature
24 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Figure 1 A simple diagram showing the eruption column and cloud for a super-eruption. A) The eruption involves the evacuation of a magma chamber, causing the rocks above
to subside. This forms a Caldera. B) Part of the upwards flow out of the magma chamber remains negatively buoyant in the atmosphere, spreading out radially as pyroclastic
flows. The deposits from these are called ignimbrites. C) Part of the eruption becomes positively buoyant thanks to the entrainment and heating of surrounding air. This rises
until it reaches neutral buoyancy. D) Once at neutral buoyancy, the ash and gas spread out to form an “umbrella cloud” in the high atmosphere.
and each super-volcano has a unique behaviour. It is
plausible to have two super-eruptions from separate centres
in quick succession.
Atmospheric impact
“I had a dream, which was not all a dream.
The bright sun was extinguished, and the stars
Did wander darkling in the eternal space,
Rayless, and pathless, and the icy earth
Swung blind and blackening in the moonless air;
Morn came and went -and came, and brought no day,
And men forgot their passions in the dread
Of this their desolation; and all hearts
Were chilled into a selfish prayer for light.”
This is an excerpt from a poem entitled “The Darkness” by
Lord Byron in 1816. His poetry was inspired by what has
become known as the “year without summer”, where the
far off Tambora volcano in Indonesia had darkened the sky
and lowered global surface temperatures after erupting in
1815. Lord Byron was not alone in his gloomy outlook, his
guest at his summer house that year was Mary Shelley, who
wrote “Frankenstein” in a morbid literary competition with
Lord Byron.
Sulphuric acid aerosol (H 2
SO 4
) is the main cause of this
atmospheric disturbance, which forms from reactions of
H 2
S and SO 2
with water (Figure 2). Atmospheric lifetimes
of H 2
SO 4
are significantly increased in the stratosphere
compared to the troposphere due to the lack of removal
by precipitation. Therefore, stratospheric residence times
are governed by gravitational sedimentation, which takes
between 1 to 3 years for historic eruptions (Robock, 2000).
For explosive eruptions, the formation of an eruption
column means that volcanic emissions can be transported
into the stratosphere, and therefore lengthen the
atmospheric residence time (Figure 2). The 1991 eruption
of Mt. Pinatubo (Philippines) was the first opportunity to
track a sulphate aerosol cloud in the stratosphere using
satellite imagery. The cloud first spread longitudinally,
encircling the globe within a few weeks (Bluth et al.,
1992). Latitudinal mixing appears to take much longer, the
Pinatubo cloud was initially constrained between 20 o S and
30 o N (Long & Stowe, 1994). Thorough mixing throughout
the stratosphere occurred within 6 months (McCormick et
al., 1995), therefore affecting the whole globe.
The solid particles (termed tephra or ash) have a short
atmospheric residence time, with most of the ash deposited
within a few weeks of eruption. Small quantities of very
fine tephra can remain suspended for a few months
(Robock, 2000), but the impact on scattering incoming
radiation is comparatively brief. Sulphur has a large effect
on the Earth’s radiation budget as H 2
SO 4
aerosol particles
have a typical radius of 0.5 µm, comparable to the peak
wavelength in the electromagnetic spectrum from our
Sun. These particles strongly scatter short-wave radiation
and partially absorb in the near infra-red (Andronova et
al., 1999). Incoming light is scattered in all directions, with
back-scattering increasing the net planetary albedo (the
reflectivity of a surface) and forward-scattering increasing
the downwards diffuse radiation (Figure 2). The backscatter
effect is more dominant, causing a net cooling at
the surface during the day as less total radiation reaches
the surface (Harshvardhan, 1979). This phenomenon has
become known as a “Volcanic Winter” (Rampino et al.,
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 25

Figure 2 A schematic diagram showing the difference between explosive and quiescent emissions from volcanoes, adapted from Robock (2000). This shows the mechanisms
behind surface cooling and stratospheric warming, and the importance of aerosols reaching the stratosphere for the longevity of the climatic impact.
1988). The absorption of sulphuric acid aerosol in the near
infra-red leads to greater adsorption of re-emitted longwave
radiation from the ground, leading to a net heating
in the stratosphere (Figure 2). This partial adsorption would
affect incoming long-wave radiation too, such that the
Moon would appear blue during a Volcanic Winter. While
the phrase “Once in a blue Moon” means to have two
full Moons within a calendar month, this may offer an
alternative explanation for the origin of this saying. The
effect of stratospheric heating has important implications
for surface temperatures during winter months, which will
be explored in the next section.
While the emissions of H 2
O, CO 2
and N 2
are dwarfed
by atmospheric concentrations, their effects on other
atmospheric processes could be significant. The availability
of water is integral to the formation of H 2
SO 4
, and it is
feasible that H 2
O and CO 2
emissions could affect other
chemical reactions that interplay with the radiation
budget, such as the impact of volcanic eruptions on
cirrus cloud formation (e.g. Sassen et al., 1995) (Figure
2). Cloud formation is a poorly constrained factor in our
understanding of the atmosphere, and may be equally
important for the radiation budget of the Earth.
Terrestrial impacts
The formation of a Volcanic Winter has a pronounced
effect on surface temperatures, which affect terrestrial
environments more than the oceans due to the relative
latent heat capacities. The observed reduction in global
radiative forcing after the eruption of Mt Pinatubo was
from 237 to 232.5 W m -2 (Sarmiento, 1993). A computer
simulation of an eruption 100x the size of Pinatubo (the
size of a typical super-eruption) predicts the initial reduction
in this case would be from 237 to 177 W m -2 (Jones et al.,
2005). In this extreme case, the Sun’s disc would no longer
be visible and the rest of the sky would be brighter due to
the forward scatter. The 100x Pinatubo simulation results in
a predicted 10 o C drop in mean land surface temperatures
(Jones et al., 2005) (Figure 3). Both evaporation rates
and the atmosphere’s water capacity would decrease in
response to cooling, slowing the hydrological cycle. This
in turn would decrease the latent heat transfer from the
oceans to the atmosphere. Heterogeneities in cooling
between continents and oceans affect the frequency,
strength and location of global circulation patterns such
as the El Niño Southern Oscillation (ENSO). Therefore, the
global response would be irregular, leading to dominant
cooling and localised warming in some instances.
26 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Figure 3 Predicted annual surface temperature changes (°C) from a modelled super-eruption eruption 100 times the size of Pinatubo (from Jones et al., 2005). All of the
temperature changes are negative. The continents have larger changes due to the inferior latent heat capacity compared to water, while the moderate cooling in western
Europe is due to Winter Warming. The annual average is still a net cooling. This extreme temperature change is predicted to return to near normal after 10 years (Jones et al.,
2005).
The adsorption of outgoing radiation by sulphate aerosols
causes stratospheric heating, particularly in the tropics
where the Sun’s rays are strongest (Figure 2). During a
Volcanic Winter, this increases the latitudinal temperature
gradient between the tropics and the poles. The net result
is a strengthening of the polar vortex. As these equatorpole
winds are affected by coriolis forces, the mid-latitude
jet streams are also strengthened which affects wind speeds
at ground level. This in turn transfers more latent heat from
the oceans to the atmosphere and from the atmosphere
to land. Therefore, during winter months the sulphate
aerosols in the stratosphere cause a relative warming of the
western sides of northern hemisphere continents (Figure
3). This ‘Winter Warming’ has been observed for historic
tropical eruptions (Robock, 2000) and is predicted for more
extreme scenarios (Jones et al., 2005).
An extreme Volcanic Winter will severely disrupt ecosystems
and flora, while the deposition of ash will kill terrestrial
biota. An increase in hard freezes would kill off vast
swathes of vegetation (Rampino & Ambrose, 2000), while a
sluggish hydrological cycle will increase drought frequency
(Jones et al., 2005). The decrease in direct short-wave
radiation and the increase in diffuse radiation will affect
primary productivity. Though there is a net decrease in
incoming radiation, several studies have argued that
increased diffuse radiation leads to enhanced net primary
productivity (Gu et al., 2003; Krakauer & Randerson, 2003).
Counter-intuitive though this sounds, diffuse radiation is
able to penetrate deeper into a forest canopy than direct
radiation, allowing a greater amount of photosynthesis per
land surface area. There will be a point where the reduction
in net radiation associated with larger eruptions outweighs
this effect.
The greatest destruction of vegetation occurs in areas
affected by tephra deposition. Most forms of agriculture
and flora are severely hampered by ash deposition
exceeding 10 mm (Sparks et al., 2005). Plants are affected
by both burial and the release of toxic metals and acids
that become attached to the tephra in the volcanic cloud.
Ecosystems that are particularly vulnerable are those with
low turnover rates, such as ponds, lakes and soils (Frogner-
Kockum et al., 2006). If flora gets destroyed by ash
deposition, observations from historical eruptions suggest
that the recovery can take decades (Fagan & Bishop, 2000;
Knight & Chase, 2005). If a continent is affected by ash
deposition, as is possible from super-volcanoes such as
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 27

Yellowstone (USA), then re-colonisation of pioneer species
will take even longer as recovery of flora must do so from
the edges of the affected area. There is new evidence to
suggest that the large Toba (Sumatra, Indonesia) eruption
around 73,000 years ago caused major deforestation in
and around India, where forested areas were replaced by
wooded to open grassland (Williams et al., 2009).
A large ash blanket can affect surface temperatures by
raising the surface albedo. Tephra can have a dry albedo
as high as 0.7 (comparable to snow) so the local radiative
effect of ash deposition leads to less heat retention by
vegetation and the reflection of a greater proportion of
incoming radiation (Jones et al., 2007). This instigates
localised relative surface cooling. This climatic disruption
from an ash blanket will last for longer than that induced
by stratospheric aerosols as a slowing of the hydrological
cycle, the scale of the ash blanket, and the cohesive
nature of fine tephra will prolong the residence time of
the ash blanket (Collins & Dunne, 1986). A key factor to
the subsequent climate forcing is the geomorphology and
location of the area affected by ash deposition. Coverage
of an archipelago will differ considerably from a continent,
as an ash blanket covering the latter would affect a
greater surface area and would have a longer residence
time. Deposition of ash into ocean surface waters has its
own capacity to alter the climate, so the ratio between
continental and oceanic effects is dictated by what
proportion of the fallout area they cover. The residence
time of an ash blanket is dependent on local precipitation
patterns, as deposition in a tropical environment would
lead to quicker erosion than deposition in a more arid
environment.
Oceanic impact
As with terrestrial ecosystems, the aerosol induced
Volcanic Winter will affect marine primary productivity. A
net decrease in direct solar radiation thins the euphotic
zone, limiting the depth to which photosynthesis can
occur. This would be a transient effect limited to the
lifetime of the stratospheric aerosols, but may affect the
health of stationary organisms such as corals. While the
temperature changes in the oceans are much less than
terrestrial ecosystems, the previously described effects
in the atmosphere and on land alter global heat and
freshwater fluxes and therefore the temperature and
salinity of the surface oceans. This is particularly important
in the North Atlantic, where the increase in winds speeds
that causes the Winter Warming lead to an increase in the
thermo-haline circulation. Again, this effect is predicted
to be transient (Jones et al., 2005), but an important
consideration nonetheless.
Another key factor is the deposition of tephra directly
into ocean surface waters, which can lead to rapid
biogeochemical changes. The solid particles in an eruption
cloud act as nuclei for condensing gases, aerosols and
metal salts (Rose, 1977; Oskarsson, 1980). These surface
accumulations are highly soluble, dissolving rapidly on
contact with water (Frogner et al., 2001; Duggen et al.,
2007). Both nutrients and toxins are released into the
water column, which have the potential to both fertilize
and poison surface water environments (Frogner-Kockum
et al., 2006; Duggen et al., 2007). This has important
ramifications for the ocean-atmosphere system, as it
has been suggested that an enhancement in primary
productivity from increased nutrient supply could increase
the biological pump for atmospheric CO 2
(Sarmiento,
1993; Watson, 1997). Mechanical mixing experiments
using volcanic ash with seawater suggests that deposition
of just 4mm of ash coverage can significantly increase
micronutrient levels (Jones & Gislason, 2008).
These are new and exciting developments but the science
is still in its infancy. Any increase in marine primary
productivity would be offset by the decrease in incoming
radiation during the Volcanic Winter. Moreover, the
potential for fertilisation is dependent on the pre-existing
chemistry of surface waters (Duggen et al., 2009). Areas
that have high nutrient levels but low chlorophyll levels,
such as the eastern-equatorial Pacific Ocean, can have
large phytoplankton bloom when enriched in key limiting
nutrients such as Fe (e.g. Morel et al., 1991). Deposition in
areas with regular replenishment of nutrients, such as areas
of upwelling, may have a more limited impact. Importantly,
nutrient release is accompanied by the release of elements
that can inhibit biological growth, including many that
are fertilisers at lower concentrations (Sunda, 1988-1989;
Bruland et al., 1991).
Ecosystem stress is further increased by a transient drop in
pH due to acids such as H 2
SO 4
(Frogner et al., 2001; Jones
& Gislason, 2008). Decreases in pH levels affect organisms
dependent on CaCO 3
for shell or skeleton formation
(Riebesell et al., 2000; Feely et al., 2004). Biogenic
carbonate precipitation is dominated by micro-organisms
(Milliman, 1993), suggesting that declines in these species
has serious implications for food web structure and health.
Decreases in pH would lead to reduced calcification rates,
malformation, and enhanced dissolution of susceptible
organisms. This is the same problem receiving attention
in the world’s media at present with the rising CO 2
levels
from human activity causing an “ocean acidification” (e.g.
Riebesell et al., 2000), except this is a natural transient
effect. Whether this effect occurs at all is dependent on
the magnitude of tephra deposition, the chemistry of the
dissolving acids (which vary considerably in quantity and
speciation between volcanoes), and the extent of diffusion
and mixing in the water column. In summary, there are
many unknowns associated with the fate of volcanic
28 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

emissions in ocean surface waters, but initial studies
suggest that in some cases the effects may be considerable.
Conclusion
I hope this summary has conveyed to you the difficulties
associated with assessing the impact of a future eruption,
as there are many variables to be taken into consideration
and there are still big gaps in our understanding. Large
eruptions have been suggested as possible catalysts for
longer term changes to the ocean-earth system (Rampino
& Self, 1992), though this relationship remains contentious
(e.g. Oppenheimer, 2002). Predictions of a 100x Pinatubo
sulphate aerosol forcing suggest that the depressed
temperatures during Volcanic Winter are insufficient to
initiate a glaciation at current climatic conditions (Jones
et al., 2005) (Figure 3). Deforestation and an increase in
surface albedo from tephra deposition encourage more
persistent snow cover (Jones et al., 2007). While these
effects last longer than the Volcanic Winter and would
act as an amplifier to the cooling signal, the scale of the
disturbance appears inadequate to instigate prolonged
changes to the climate at current conditions.
While the aerosol induced Volcanic Winter is the dominant
forcing for historic eruptions, there are other factors that
may only become significant for larger eruptions. Terrestrial
surface effects can have a large effect on the carbon cycle,
such as changes to soil respiration, deforestation, and
changes to primary productivity. In marine environments,
variations in marine primary productivity can have a large
impact on atmospheric CO 2
levels. However, predicting
these changes is extremely difficult, and could feasibly
be unique for each eruption as much depends on the
time, location, chemistry, and magnitude of the eruption.
Timescales of ecosystem stresses, fertilization events,
and recovery of flora and fauna are poorly constrained,
although it is plausible that these disruptions could
combine to significantly enhance decadal, centurial, or even
millennial climatic variability.
Super-eruptions that have occurred in the Upper
Pleistocene have been implicated as bottlenecks for human
and animal populations, based on evidence of overall low
human genetic diversity (Rampino & Ambrose, 2000).
Major historic eruptions have caused famines, plagues,
and crop failures, so the impact of an event the scale of a
super-eruption will have serious implications for food web
structure and health. If a super-eruption were to occur
in the near future (a very big “if”) the impact would be
catastrophic. Agriculture and water supply would be initially
devastated in many communities, with supplies unable
to sustain the current human population. The Northern
Hemisphere would be particularly threatened as this is
where most food production occurs and where population
densities are highest (Self, 2006). Such large events are
extremely uncommon, so the chances of one occurring
in our lifetime are very slim. However, there will be future
super-eruptions, so it is imperative that we learn all we can
about such phenomena.
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W.L., Spinhirne, J.D., Eloranta, E.W., Hagen, D.E. & Hallet, J. (1995)
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(2005) Supereruptions: Global Effects and Future Threats. Report of a
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A more comprehensive list of references can be
obtained by emailing me at the address below.
Morgan Jones
Morgan.jones@lmtg.obs-mip.fr
"Lava contains vesicles, which are small air
holes which can indicate the direction of the
Earth’s magnetic field at the time."
30 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Greenhouse to icehouse:
Arctic climate change 55–33 million years ago
Ian C. Harding
Abstract
Until recently little had been known about the
palaeoclimatic or palaeoceanographic history of the
Arctic, a region that has a major role in regulating
modern climate. However, over the past five years
the availability of new study material has permitted
the first glimpses of the dramatic events that have
characterised the past 55 million years of Arctic
history, from the ice-free greenhouse climate of
the early Palaeogene to the onset of Northern
Hemisphere glaciation.
Introduction
The Arctic has a crucial role to play in global climate
regulation due to the interaction between the atmosphere,
oceans and ice cover, and the transport of water, heat and
salt – not least in being a major site for the generation
of cold bottom waters to drive the global conveyor belt
(Rahmstorf, 2002). However, extensive media coverage
has recently demonstrated the amplified effect of
anthropogenically-induced climatic warming on this region
(IPCC AR4, 2007), resulting not only in major reductions
in the area and thickness of summer sea ice, the area of
multi-year sea ice (Comiso et al., 2008; Stroeve et al.,
2008), but also the extent of fresh water discharge into
the Arctic (Peterson et al., 2002). Predictions have been
made that the Arctic will experience ice-free summers
by the year 2100 (Boe et al., 2009), although there are
indications this may be a conservative estimate. Indeed
the summer of 2009 saw the first trans-Arctic crossing by
cargo ships from eastern Asia to Europe without the aid
of ice-breakers (Paterson, 2009). However, whilst there is
still significant uncertainty regarding predictions of future
climate evolution in the Arctic, we have recently begun
to understand more about past climatic variations in this
region, which may help to constrain climate projections.
Climatic conditions of the geological past can be
deduced from a variety of different proxies, from the
sedimentological to the geochemical. Just as desert
sandstones, evaporites, coals, tropical limestones, laterites
and bauxites can provide evidence of ancient warmth,
cold climates can be inferred from the presence of tillites,
ice-rafted dropstones and the surface textures present on
mineral grains ground in continental ice masses (Eldrett
et al., 2004; Eldrett et al., 2007). Micropalaeontology
also has a major role to play in palaeoclimatic and
palaeoceanographic studies, by examining the evolution
and extinction of different microscopic organisms and
their palaeogeographic distributions. However, in order to
quantify the magnitude of climatic change, geochemical
studies can be undertaken on such microfossils: such as
stable oxygen isotopes or magnesium/calcium ratios. Such
measures have been successfully used to discern the course
of climatic events 65-33 million years ago (Palaeogene) in
other parts of the world, from the Antarctic to the Pacific
Ocean (Zachos et al., 2001; Figure 1), often by using the
continuous sedimentary records locked in deep-sea cores
drilled successively by the Deep Sea Drilling Project (DSDP),
Ocean Drilling Program (ODP) and the current Integrated
Figure 1 Benthic oxygen isotope curve for the Palaeogene, illustrating the climatic
events discussed in the text (modified from Zachos et al., 2001).
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 31

Ocean Drilling Program (IODP). Regrettably it has proven
extremely difficult to determine conditions over this period
in the Arctic, firstly as there is a lack of both land-based
outcrop material or deep-sea sediment cores available to
study, and that material which is available contains very few
calcareous microfossils to utilize for geochemical analysis
(Eldrett et al., 2007).
However, new research has recently begun to clarify
climatic events in high northern latitudes, firstly by
identifying and producing accurate ages for an almost
complete Palaeogene record from ODP core 913B from
the Norwegian-Greenland Sea (Eldrett et al., 2004), and
for outcrop sections on the island of Vest Spitsbergen
in the Svalbard Archipelago (Harding et al., 2008). In
addition, the cores resulting from the first European-led
IODP cruise to the high Arctic, the Arctic Coring Expedition
(ACEX), have also produced new material with which
to examine northern high latitude climatic fluctuations
(Moran & Backman, 2006). In order to combat the lack of
the conventional calcite-walled microfossils in these cores,
researchers have turned to the very rich assemblages of
organic-walled microfossils in these cores which include
the remains of planktonic dinoflagellates and terrestriallyderived
spores and pollen (Eldrett et al., 2004; Eldrett et
al., 2009). New organic geochemical palaeotemperature
proxies have also been developed: the TEX 86
sea-surface
temperature (Schouten et al., 2002) and CBT/MBT soil/air
temperature (Weijers et al., 2007a) proxies. These are based
on quantifying the abundance of certain biomolecules
(membrane lipids) produced by, respectively, marine and
terrestrial crenarcheotal bacteria.
The PETM (~55 million years ago)
The PETM is identified by a massive negative stable carbon
isotope perturbation in both carbonate and organic
carbon which marks the Palaeocene-Eocene boundary,
approximately 55 million year ago (Sluijs et al., 2007).
This negative carbon isotope excursion is believed to
have resulted from an input of at least 1.5 x 10 18 g of
13
C-depleted carbon, probably in the form of methane
from dissociating seafloor gas hydrates (Dickens et al.,
1995), an amount similar in magnitude and composition to
current and future predictions of fossil fuel emissions. The
PETM lasted for some 170,000 years, and evidence from
low and mid-latitude sites indicate that this geologically
transient event was accompanied by major environmental
perturbations including a 4–8 ºC rise in surface and deepsea
temperatures and major terrestrial and marine biotic
changes (Sluijs et al., 2007). However, until the ACEX core
material became available, virtually nothing was known
about this event in the high northern latitudes.
Both the sediments from the ACEX core and the Central
Basin of Vest Spitsbergen have yielded a mass occurrence
of the PETM marker-species of dinoflagellate Apectodinium
augustum (Sluijs et al., 2006; Harding et al, 2008; Figure
2). This species first appeared in tropical latitudes before
the PETM, but migrated polewards as global sea surface
temperatures rose during the warming event (Crouch et
al., 2001), and provide an initial indication of how elevated
sea surface temperatures may have been in the Arctic at
this time. Just how high the temperatures were has been
estimated using the TEX 86
(Sluijs et al., 2006) and CBT/MBT
(Weijers et al., 2007b) organic geochemical proxies – and
A striking picture of Arctic climatic perturbations has
started to emerge from these cores, specifically three
major events (Thomas et al., 2006; Zachos et al., 2001):
the Palaeocene-Eocene Thermal Maximum (PETM), the
mid-Eocene Azolla Event and the greenhouse to icehouse
transition at the Eocene-Oligocene boundary (EOB).
Figure 2
a) Negative stable carbon isotope excursion as recorded in the Longyearbyen
section on Vest Spitsbergen.
b) Absolute abundance data for the PETM-marker species of dinoflagellate cyst
Apectodinium augustum (inset). Grey band marks main isotope excursion event.
32 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

the results are extremely striking. It has been estimated that
Arctic (summer) temperatures increased from around 18 ºC
to over 23 ºC during this event (Sluijs et al., 2006; Weijers
et al., 2007b). These extremely high values indicate that
the Arctic would probably have been ice-free year round.
The temperatures are so high that climate models find
them difficult to replicate, indicating that greenhouse gas
concentrations must have been much higher than those
of the present day and probably operated in conjunction
with other feedback mechanisms to result in such high
early Palaeogene Arctic temperatures (Sluijs et al., 2006).
Sedimentological evidence from the Vest Spitsbergen
sections indicates that at the height of the warming
event sea level reached its maximum level (possibly due to
thermal expansion), resulting in a marine incursion, water
column stratification, and lowered bottom-water oxygen
levels. Stratification was further enhanced by surface water
freshening which was caused by an increase in terrestrial
runoff – another consequence of the global warming
– indicated by huge abundances of low salinity plankton. A
picture emerges of an ice-free Arctic PETM characterised by
high eustatic sea levels, and stratified, deoxygenated water
masses supporting unusual, high-dominance plankton
assemblages.
The Azolla Event (~50 million years ago)
The dramatically enhanced high northern latitude
precipitation indicated by the Arctic PETM results
described above corroborates fully coupled palaeoclimate
simulations of the early Palaeogene greenhouse world.
However, the ACEX core provided some even more
extraordinary evidence for such conditions in the form of
massive abundances of the reproductive structures of the
free-floating fern Azolla found in middle Eocene Arctic
sediments (Brinkhuis et al., 2006). Azolla was clearly
flourishing in the restricted Arctic Basin surface waters
(Figure 3). These surface waters are beieved to have been
freshened by increased terrestrial runoff, as the only
other microfossil present in these sediments are also of
freshwater affinity: diatoms and chrysophyte cysts. These
freshened surface waters existed in the Arctic for a period
of some 800,000 years. Lower concentrations of Azolla
are also found in marine sediments from the Nordic seas
surrounding the Arctic, and it has been suggested that
these occurrences may represent spill-overs of freshwater
from the Arctic Ocean which transported the fern
remains further south (Brinkhuis et al., 2006; Figure 3).
An increase in salinity and sea surface temperatures seem
to have terminated the Azolla blooms in the Arctic Basin.
However, it has been postulated that the high Palaeogene
atmospheric carbon dioxide levels could have been reduced
by the Azolla blooms, CO 2
being converted into organic
carbon that was then locked into Arctic bottom sediments,
so high are the concentrations of Azolla and other organic
material in these middle Eocene sediments.
The Eocene-Oligocene greenhouse-icehouse transition
(~33.5 million years ago)
The boundary between the Eocene and Oligocene epochs
(~33.5 million years ago) is a critical phase in Earth history.
An array of geological records, including a rapid two-step
shift in benthic foraminiferal oxygen isotopes (the
Oi-1 glaciation event), and climate modelling experiments
indicate a profound shift in global climate, from a world
largely free of polar ice caps to one in which Antarctic ice
sheets approached their modern size (DeConto & Pollard,
2003). However, until recently there was very little known
of the early glaciation history in the high northern latitudes
(Zachos et al., 2001). New analyses of ODP Site 913B has
yielded evidence for extensive ice-rafted debris, including
dropstones up to 7cm in diameter, in late Eocene to early
Oligocene sediments from the Norwegian–Greenland Sea
that were deposited between about 38 and 30 million
years ago (Eldrett et al., 2007). These dropstones are likely
to have been rafted to the site of deposition by glacial ice
(shed from nearby East Greenland) rather than sea ice,
something corroborated by grain surface structures. These
data suggest the existence of isolated glaciers on Greenland
about 20 million years earlier than had been supposed
previously (Eldrett et al., 2007).
Figure 3 Palaeogeographic reconstruction of the Arctic Ocean during the Azolla
event, showing positions of the ACEX site (ODP Site 302-4a) in the Arctic and ODP
Site 913B in the Norwegian-Greenland Sea. Large white arrows indicate suggested
routes of freshwater spill-overs carrying Azolla into the Nordic seas (based on
Brinkhuis et al., 2006).
Other studies have now corroborated the sedimentological
evidence for climatic deterioration in the Arctic prior to the
Eocene-Oligocene boundary (EOB). Our studies using the
CBT/MBT proxy indicates a mean annual air temperature
(MAAT) in the late Eocene of ~13–15 °C, with a gradual
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 33

Figure 4
a) Striated dropstone from Eocene sediments of the ODP 913B core.
b) Quartz grain exhibiting surface features (e.g. conchoidal fractures) resulting from abrasion in continental ice.
c) Electron micrographs of warm indicator Eocene pollen grains extracted from ODP 913B samples.
long-term cooling of ~3–5 °C starting near the EOB
(Schouten et al., 2008). We have now corroborated this
evidence by employing another set of proxy data derived
from the well preserved spore and pollen assemblages
extracted from samples from Site 913B. These terrestrially
derived microfossils have permitted the determination of
the first high northern latitude terrestrial climate estimates
for the Eocene to Oligocene interval (Eldrett et al., 2009),
including mean annual precipitation and temperature
estimates. By comparing the known climatic tolerances
of the fossil forms with their nearest living relatives, a
method known as Bioclimatic Analysis has indicated that
the most striking temperature variation is represented not
in mean annual or warm monthly mean temperatures,
but in the cold-month (winter) mean temperatures, which
demonstrate a cooling of ~5-6 ºC down to values of
0–2 ºC across the EOB. This therefore indicates increased
seasonality set in before the Oi-1 event and serves to
demonstrate that the stable oxygen isotope shift across the
EOB records both a temperature decrease and a build-up of
ice. However, the relatively warm summer temperatures at
that time mean that continental ice on East Greenland was
probably restricted to alpine outlet glaciers (Eldrett et al.,
2009, Weijers et al., 2007a).
Conclusions
The new palaeoclimate records described above have
radically improved our understanding of the dramatic
environmental changes that occurred through the Arctic
Palaeogene. By illustrating some of the climatic variability
34 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

experienced by this region have been over the last 55
million years, we can provide a geological context for those
developing predictions for the future climatic development
of this region.
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(2008) The Palaeocene-Eocene Thermal Maximum in the high Arctic:
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J.S. (2007b) Warm arctic continents during the Palaeocene-Eocene thermal
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Ian Harding
School of Ocean & Earth Science, University of
Southampton, National Oceanography Centre, European
Way, Southampton, SO17 3RT.
ich@noc.soton.ac.uk
Cause of Mass Extinction...... “the earth
was hit by a giant ammonite”
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 35

‘Climate Change.........Save the Planet’
This is the cry we hear from those demanding action
on reducing global warming. But shouldn’t it be “Save
the Developed Nations’ Lifestyles” as the planet
will remain even when the climate changes – it’s our
standard of living that will change.
As Earth Scientists should we be considering how geology
and the exploitation of our Earth’s finite resources fit into
this changing global human picture?
If you teach Earth Science you are already interested in how
the Earth is formed, how Earth systems work over time
and how we explore and exploit the Earth’s resources from
soil to oil. The next step could be to take this knowledge
further and into the future .........
• What Earth resources will be left in the future?
• How sustainable are our resources?
• When will they run out?
• What problems will Earth Scientists be solving in 40
to 50 years time.
• What skills do we teach our students today to be of
use in the future?
These links have been put together by an ESTA member
with an interest in fostering interdisciplinary approaches,
who has endeavoured to select a few starting points,
which may not be common knowledge in some geological
circles, but that have relevance to both present and future
generations. Have a look at the list, it’s compiled so that
anybody interested in the how Earth Science will meet our
future needs can, at no expense except their time, view
some relevant material covering soil, food, peak oil and
sustainability.
And just to make sure you have the alternative arguments
for the causes of global warming I have put in an extra
website, number 8 below – an interesting geological
viewpoint to promote discussion with your students.
What do you think? How are we going to cope in a
changing world?
Let’s have a discussion, is this topic relevant to the Earth
Science curriculum? Environmental Science curriculum?
Citizenship curriculum? Why don’t you tell us your views?
Ros Todhunter
ESTA Secretary
36 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Climate Change . . . Save the Planet links
1. The award-winning documentary by Megan Quinn: “The Power of Community: How Cuba survived Peak
Oil.” This is a well informed documentary. It brings home the reality, rather than speculation, of basic skills needed
in Oil shortage, and how no one person or profession is exempt – all will need to adapt. It is an ideal example of
people who had to adapt quickly to living local with very little warning. There is also the documentary’s website:
www.powerofcommunity.org/cm/index.php Megan Quinn is considered by many a good spokesperson for the
next generation. She has studied peak oil, foreign policy and is trained communicator. See written interview:
www.inthewake.org/quinn1.html
2. Further to the case study of Cuba, Monty Don (president of the Soil Association) includes three gardens from
Cuba in Programme One of his BBC series “Around the World in 80 Gardens”: www.bbc.co.uk/gardening/
tv_and_radio/aroundtheworld_index2.shtml#programme_one This site has links to the Cuba Organic
Support Group (COSG)
3. The DVD by EF Schumacher “Life of the edge of the Forest”, 1977 touches on the End Of Growth Economy.
It is available through http://www.efschumacher.co.uk/index.htm The EF Schumacher Society: linking people, land,
and community by building local economies. http://www.smallisbeautiful.org/index.html
4. Richard K. Lester, MIT Professor of Nuclear Science and Engineering and Director of the Industrial Performance
Center. Transcript of speech addressing US governors on 14th July 2008, “Energy Innovation: What’s Here and
What’s Coming” http://www.theoildrum.com/pdf/theoildrum_4323.pdf
5. Dr Alice Roberts is a senior lecturer of Anatomy, Archaeology and Anthropology at Bristol University, as well as a
writer and media presenter. Her BBC Radio 4 programmes, “Costing the Earth, The Great Mineral Heist” touches
on the depletion of mineral content in some soils and food: www.bbc.co.uk/radio4/programmes/people/
VGVmL25hbWUvcm9iZXJ0cywgYWxpY2UgKGJiYyBwcmVzZW50ZXIp
6. Professor Iain Stewart’s comment at the ESTA 2009 Conference Keynote lecture was approximately: ‘If we are
intelligent, now is the time to show it.’ Could this theme be developed to including world food issues and soil
degradation? Link to his television series, “Earth: the Power of the Planet”: www.plymouth.ac.uk/PlanetEarth
7. Richard Heinberg of the Post Carbon Institute delivered the Soil Association’s Lady Eve Balfour Memorial
Lecture 2007, “What Will We Eat When The Oil Runs Out?” Transcript: www.energybulletin.net/node/38091;
Short video clip: www.youtube.com/watch?v=_S0RvVrdvF0 Heinberg also has his own website: www.
richardheinberg.com/Home.htm; and Post Carbon Institute www.postcarbon.org/
8. Global warming? Don’t wait up! The Earth has her own tricks to keep the carbon count in control By Ian Plimer,
Professor of Geology at the University of Adelaide. Read more: http://www.dailymail.co.uk/debate/article-
1231673/Global-warming-Dont-wait-The-Earth-tricks-carbon-count-control.html Ian Plimer’s book, Heaven
and Earth: global warming – the missing science, is published by Quartet Books.
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 37

The Tomlinson-Brown Trust:
Supporting the Teaching of Earth Sciences
Tex Wales
Abstract
The Tomlinson-Brown Trust (TBT) is a charitable trust
which welcomes applications for funding from schools
across the age range needing financial support for
Earth Science initiatives. This article describes how the
Trust came about, some of the initiatives it has already
supported and how to apply for a grant.
Introduction
Between the late 1930s and the early 1960s, Yardley, a
co-educational Grammar School situated in Birmingham’s
inner city, was one of the very few secondary schools
throughout the UK which offered Geology as a Higher
School Certificate/A Level subject in its 6th Form. In fact,
while not unique, it was very special and arguably the lead
school in this science in England and Wales.
Geology had been introduced into the 6th Form curriculum
by Dr. Mabel Tomlinson (the senior Geography teacher),
a distinguished academic and field Geologist whose
research had provided the definitive interpretation of the
River Severn terraces. On her retirement in 1959 she was
succeeded by Geoff Brown who was privileged to carry on,
expand and enhance this tradition into the mid 60s.
These two teachers inspired generations of pupils with
their enthusiasm for Earth science. Each year they made
it possible for the brightest to go on to University and
subsequently to take up distinguished careers in many fields
of the Earth Sciences, particularly in teaching, research in
the petroleum and mining industries, and the Geological
Survey.
public awareness of Earth Science issues. This is done by
raising and managing funds to make awards accessible
to school students (under 18 years), schools and youth
organizations and to individuals or groups who seek
financial support in order to pursue practical projects (field
or laboratory work etc).
The Trust relies on donations from career geologists and
others wishing to support the teaching of Earth Sciences.
TBT’s mission is to promote the study of Earth Sciences
in both Primary and Secondary Schools as a component
part of the Science curriculum. In so doing help create an
increased knowledge, understanding and awareness of the
natural world, its present condition and future challenges.
Being a relatively small, private charity TBT needs to target
its support to what it considers as ‘value for money’
initiatives.
This currently includes:
• Supporting field visits – provision of additional
funding that would make a field trip viable, and/or
help particularly deserving pupils who perhaps
might not otherwise have the opportunity of
participating in a field trip.
• ‘Pump priming’ new Earth Sciences initiatives.
TBT has previously supported:
Rock and Fossil Road show for Primary Schools
The “Rock and Fossil Road Show” targets Key Stage 2
classes of up to 30 primary aged pupils. Pupils (age range
Fifty years on, the teaching of Geology at Yardley has long
since gone. Thankfully however, the tradition lives on in the
form of the Tomlinson-Brown Trust.
The Tomlinson Brown Trust
The Trust was formed in 2004 by a group of these
Yardley Earth Scientists and its interest was focused upon
the Abberley and Malvern Hills Geopark (Hereford and
Worcestershire Earth Heritage Trust). The general aim is to
promote and encourage the appreciation, education and
38 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

14-18) from King Edward VI Five Ways School, Birmingham,
support the Road Show by each supervising 4 young pupils
in the testing of rock with acids etc. and the handling of
specimens of igneous, sedimentary and metamorphic rocks
and fossils.
TBT funds helped with transport costs for the road show
which to date has visited twelve primary schools.
Field visits to Iceland
TBT supported field trips to Iceland for King Edward VI Five
Ways School, Birmingham in 2008 & 2009 by providing:
• assistance with general transport costs
• individual grants to students without which they
would have been unable to attend field trips
Earth Heritage Trust – ‘Champions Project’
The Champions Project aims to increase community
awareness and understanding of Earth Heritage by
encouraging local groups to champion RIGS sites on their
doorstep. This involves people in monitoring site conditions;
reporting any changes and/or threats to the site; using the
site for education and/or recreation and learning about
its unique importance and place in the wider geology and
landscape of the area.
For further information about the Champions Project
contact the project manager Eve Miles: Phone: 01905
855184 or email e.miles@worc.ac.uk website http://
www.earthheritagetrust.org TBT has agreed to support
selected schools with funding to help them prepare for
Champions Project activities.
Applications
TBT welcomes applications for funding from primary and
secondary schools who require financial support for Earth
Science initiatives.
For more information about TBT
and its support activities or an
application form please contact:
Tex Wales, Secretary,
Tomlinson-Brown Trust
0121 705 5805
Note from the editor – there is now a link to TBT on the
ESTA website under resources. See http://www.estauk.net/tomlinsonbrown_trust.html
"Radon can easily mix with the reservoir
water and intoxicate the water which would
affect the drinkers of the water."
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 39

Can the design and construction of new
school and college buildings be compatible
with environmental sustainability?
Sustainability is all about meeting the needs of the
present without compromising the needs of future
generations. The need to reduce our CO 2
emissions
and energy consumption is one of our most pressing
concerns and according to CABE (The Commission
for Architecture and the Built Environment) “The
construction and servicing of buildings is responsible
for approximately 50% of UK carbon emissions.
Improving the energy efficiency of new and existing
stock is therefore essential if we are to achieve the
government’s target of a 60% reduction in CO2
emissions by 2050”. (See: http://www.cabe.org.uk/
publications/environmental-sustainability-and-thebuilt-environment)
This short article outlines how an ESTA member (as Head of
Geology and Assistant Principal with responsible for Estates,
Premises & Services) worked in partnership with architects
and construction teams on a project to create a new library
and learning centre in a Further Education college. One
challenge of this project was to discover how the design
and construction a new educational building that could be
compatible with environmental sustainability.
About the building project
The main aim of this project was to create light, airy
learning and teaching spaces in a new learning resources
block as a replacement for an existing library area. This
original library, housed in a typical flat-roofed building
of the 1960s, was cramped, had limited work areas and
insufficient computing facilities. The new three-storey
building (Figure 1) was planned to provide an inviting and
attractive learning environment where students could
easily access a library and learning resources and would
be provided with a range of work spaces and computing
facilities.
How did the project team plan to meet environmental
sustainability themes?
The team not only considered the environmental impact
from the design, construction and operation of the building
project, but also considered the environmental impacts with
respect to the materials and equipment that would be used
in the building upon its completion.
Environmental impact from the design, construction
and operation of the project
The following design features were included in the project
as an attempt to ensure the programme was compatible
with environmental sustainability:
Figure 1 The Learning Curve
• The building has a two-tiered roof with a “green
roof” at the lower level – a living roof planted
with Sedum (an alpine plant), to retain and
manage rainwater, help to improve air quality, add
insulation and provide diverse habitats for small
plants and insects (Figure 2).
• The design incorporated wind catchers – these are
40 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Figure 2 The living roof planted with Sedum
environmentally friendly methods of providing
natural ventilation to the space, so there would
be no need to make use of mechanical ventilation
systems run by electricity (Figure 3). Wind catcher
systems are designed to operate so that warm air
rising to roof level decreases the air pressure within
buildings, allowing cooler air to enter the via the
units. The resultant change in air pressure produces
sufficient airflow. Furthermore, wind blowing onto
the windward side of a ventilation stack increases
the throughput of air and encourages stale and
stagnant air to be extracted through the leeward
side of the roof unit.
• Sun pipes were included, providing shafts of
natural light into the upper floor of the building
and helping to reduce electricity consumption. The
sun pipe system (Figure 4) makes use of the Sun’s
renewable energy by reflecting and intensifying
sunlight down through highly reflective, mirrorfinish
aluminium tubes.
• High value insulation materials were integrated
into the design – the specification exceeded U
values (overall coefficient of heat transmission) at
the time of construction. (Note: U values indicate
the heat flow through materials)
• The 3-storey block was constructed on a sloping
ground surface and the site layout of was planned
so that part of the lower ground floor was set
into the ground. It is 1.8m below existing ground
Figure 3 A wind catcher
Figure 4 The sun pipe system reflects and intensifies sunlight down through highly
reflective, mirror-finish aluminium tubes.
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 41

level, reducing the visual impact and scale of the
block. This means that from outside the college’s
perimeter fence it gives the impression of a 2-
storey building. There are only windows on one
side of the building on all floors. Infrequently-used
storage rooms are located on the ‘dark’ side,
below ground level, reducing electricity costs for
lighting.
• The building is predominantly UVPC-free.
• MDF (medium density fibreboard) is not used for
the construction of the building.
• No carcinogenic construction materials were used
in the building of the Centre.
• The building has a siphonic drainage system that
incorporated one full-bore pipe, which is more
efficient than the traditional 6 or 7 rainwater pipes
that could have been used on a building of this
size. Consequently this drainage system avoids
wasting building resources because it significantly
cuts down the amount of plastic pipe work
required.
Environmental impact with respect to the materials
and equipment used in the building.
The following items were included in the scheme with
a view to try to be compatible with environmental
sustainability:
• The project included installation of energy efficient
PCs, scanners & printers i.e. machines that shut
down automatically when not in use.
• MDF (medium density fibreboard) was not used in
the Centre’s furniture.
• Energy efficient hand dryers were installed in the
toilet facilities and the toilet rolls are largely made
of recycled material.
• The Centre’s printers and photocopiers use paper
made with a high percentage of recycled material
or paper manufactured from sustainable forests.
• Notice boards in the Centre are made of board
that contained a high proportion of recycled
material.
• Permanent display boards in the Learning Centre
are used to raise environmental awareness
(amongst staff and students) by having information
about environmental issues on display.
• Collection facilities were installed in the building
to collect batteries, plastic bottles, aluminium cans,
printer cartridges and paper for recycling.
Conclusion
This project showed that an environmentally sustainable
building could:
1. Reduce energy use, pollution and water use.
2. Recycle materials and hence reduce waste during
the building’s lifetime.
3. Use low environmental impact materials produced
from renewable sources.
4. Be managed to ensure the buildings’ sustainable
design features are used effectively.
From my (limited) experience I would therefore suggest
that the design and construction of new school or
college buildings can be compatible with environmental
sustainability. At the start of this project in 2000/1, the
key idea of integrating environmental sustainability into
the design process from its beginning was a novel idea,
but since this project was completed it is encouraging to
note that there has been considerable progress towards
developing a code for sustainable buildings. (See:
www.towards-sustainability.co.uk/issues/built/ and
www.ukgbc.org/site/). Moreover a better buildings
initiative, recognising success through the annual Better
Public Building Award (www.betterpublicbuildings.
org.uk), has since been established.
I hope that this brief article will highlight a number of
useful points that could be helpful either to initiate debate
with students about environmental sustainability issues
in the news or to increase their awareness of how such
issues can be related to their own ‘work environments’.
The study of geology engages students in a range of issues
that include sustainable development. By suggesting to
students how, even on a local or small scale, the buildings
they use can encourage living and working patterns that
reduce consumption of natural resources and increase
biodiversity could be useful in helping our students
develop positive attitudes regarding “protection and
responsible stewardship of their environment” (part of the
“wider curriculum” referred to in the new AS/A Geology
specifications).
Other useful links
www.greenflagaward.org.uk
www.buildingforlife.org
Maggie Williams
hiatus@liv.ac.uk
42 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Peneplains and plate tectonics
Mark Hayward
Abstract
Regional-scale erosion surfaces known as peneplains
preoccupied geomorphologists for about sixty years of
the twentieth century. By the time the theory of plate
tectonics had become embedded in the Earth sciences,
the peneplain concept had virtually disappeared
from view. Recent research, however, indicates that
the concept, albeit in a revised form, could have an
important role to play in understanding landforms on
a large scale in the context of plate tectonics.
Introduction
It is surprising that two recent physical geography texts
(Holden, 2008 and McKnight & Hess, 2008) devote no
space to landforms at the regional scale. The latter, an
American text, includes a map of world landform regions,
but states that the pattern is random and will not be
considered any further! The other text, a widely used
British one at undergraduate level, covers plate tectonics
briefly. The explanation of regional-scale surface features
is an important aspect of geomorphology that has been
quite neglected. The theory of plate tectonics provides a
framework to explain the distribution of landform regions.
The peneplain concept provided geomorphologists with
a phenomenon that can be mapped and correlated from
place to place at a regional scale (morphostratigraphy).
The quantitative revolution in geography from the
1960s onwards led to an emphasis on smaller-scale
process studies. This was a paradigm shift away from the
dominance of Davisian denudation chronology, which
underpinned the peneplain concept. Meanwhile, a better
understanding of tectonics undermined the eustatic
view of world-wide changes in base level that many
geomorphologists believed in.
It is not intended to argue for a return to W M Davis’s cycle
of youth-maturity-old age that dominated geomorphology
for half a century towards the end of the last millennium.
This article will focus on one of his important concepts,
the peneplain, and summarise some recent research by
Earth scientists, while setting it alongside arguably its
stratigraphic counterpart, the unconformity. Google
Scholar was used to search for relevant recent research,
using the keywords peneplain, planation surface and
unconformity. Most ‘hits’ were in the form of abstracts,
but several were pdf files. Unless otherwise stated, the
term peneplain will be used in a broad sense, following
Fairbridge & Finkl (1980): ‘a polygenetic surface of low
relief’: in other words, an extensive lowland formed by
weathering and erosion.
Do peneplains exist?
Peneplains were once fundamental to geomorphological
analysis (Figure 1). Phillips (2002) however, states that
‘despite more than a century of effort, no convincing
example of a contemporary peneplain has been identified,
and the identification of relict peneplains is uncertain and
controversial’. He sets out to demonstrate mathematically
that the relationship between erosion and deposition rates
and uplift or erosion are ‘dynamically unstable’. Therefore,
tectonic stability alone is insufficient to account for the
lack of peneplains, and must be considered together with,
for example, changes in sea level, climate and isostatic
changes.
Nevertheless, whether considering large-scale surface
features of the Earth, or extensive unconformities in the
geological record, evidence of widespread erosion surfaces,
or planation surfaces (therefore peneplains in Fairbridge’s
sense) is incontrovertible.
Examples of peneplains in recent research
Coltori et al (2007) write that ‘Planation surfaces are
an old-fashioned topic in geomorphology, but they are
nevertheless important where they make up much of
the landscape’. Furthermore, ‘These surfaces indicate
that eastern Africa underwent long episodes of tectonic
quiescence during which erosion processes were able
to planate the surface at altitudes not too far from sea
level’; in other words they are peneplains in the Davisian
sense. Successive planation leads to stepped topography.
Peulvast & Claudino Sales (2004) have re-evaluated
stepped planation surfaces in North East Brazil, relating
them to continental rifting and Atlantic opening in the
Cretaceous. Campbell et al (2006) document the Neogene
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 43

Figure 1 Wales is a classic example of an area mapped in terms of planation surfaces interpreted as Davisian peneplains (Brown, 1960) with successive incision events related
to eustatic sea level fall. This view is of the Black Mountains near Abergavenny.
geological history of lowland Amazonia. They describe a
major peneplain, an isochronous, Pan-Amazonian feature
that formed following the early to mid-Miocene phase of
Andean tectonic uplift. Peneplanation may have begun
about 15 Ma and ended about 9.5–9.0 Ma. A thin cover
of sediments was then laid down over most of lowland
Amazonia, burying the peneplain, which is readily observed
in riverbank exposures as an angular unconformity. The
authors correlate this unconformity with surfaces elsewhere
in South America, linking the erosional phase to ‘a common
cause, which is interpreted to be the still on-going collision
between the South American and Nazca tectonic plates’.
The Appalachian region of eastern North America was a
classic location for identifying peneplains. Stanford et al
(2001) correlate late Cenozoic fluvial deposits and erosional
landforms and Coastal Plain marine deposits to identify
periods of valley incision and planation, with incision
related to glacioeustatic lowering of sea level during
growth of the Antarctic ice sheet in the Middle to Late
Miocene and initiation of Northern Hemisphere ice sheets
in the Late Pliocene. The authors make the bold claim
that planation in coastal regions of low relief on passive
margins can be achieved in less than 20 million years, with
dissection in less than 5 million years.
As can be seen from the above, Earth scientists are still
continuing to identify peneplains, and these are sometimes
interpreted in the original sense of an erosional lowland
reduced to near base level at the end of an extended
period (cycle?) of erosion. However, it is preferable to
use the meaning of the term adopted by Fairbridge
(above). He believed that the complex history of subdued
cratonic surfaces, with their occasional pedological
evidence, veneers of marine deposits, and periodic
tectonic disturbances, needed a multidisciplinary
approach: which called for a ‘meeting of the minds’
between geomorphology, soil science, stratigraphy,
palaeoclimatology and plate tectonics (Fairbridge, 1988).
Battiau-Queney (1996) reviews a number of weathering
indicators that can be used to study past surfaces, but
stresses that weathering alone is unlikely to be able to
produce extensive lowlands, and that there may have been
geomorphological systems in the past with no modern
analogues. Fluvially-based erosional explanations, she
claims, are likely to be inadequate as well.
Peneplains and tectonic activity
Erosion surfaces have been observed in alpine locations.
Babault et al (2005) produced a very interesting paper on
the Pyrenees, where high elevation peneplains had been
44 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Figure 2 Planation surfaces (peneplains in the broad sense) continue to be identified, including in high relief areas. This is the Alps seen from Thun in Switzerland.
traditionally interpreted as a product of fluvial erosion
to base level. These authors propose an interpretation in
which deposition of material from the highland zone in the
piedmont zone causes a rise in the base level of the range,
which greatly reduces the erosive efficiency of the drainage
system and leads to the progressive smoothing of the relief.
They believe that their model could apply to other alpine
ranges. Babault and colleagues (2007) have subsequently
devised an experimental model supporting their field
observations. This idea has generated much debate, and
the interpretation of the Pyrenees has been questioned
(e.g. Sinclair et al 2008). In the Alps themselves, Linder
(2005) describes where Cretaceous sediments are cut off
by a major unconformity. On this surface occur a number
of fossil dolines (limestone solution hollows). This period of
erosion was caused by the emergence of the
area from the shrinking Tethys Sea due to forebulge during
the Early to Middle Eocene. Sinclair et al (op. cit.) believe
that the Alps (Figure 2) and the Apennines are active
mountain belts whereas the Pyrenees are not. Coltori
& Pieruccini (2000) discuss the significance of a major
planation surface cutting across the Apennines in Italy.
The authors noted that: (1) it is better preserved on harder
rocks; (2) it cuts strata ranging in age from Palaeozoic to
early Lower Pliocene; (3) it smoothed-off tectonic structures
older than early Lower Pliocene; (4) it is buried below
continental and marine deposits younger than late Lower
Pliocene; (5) it is displaced and deformed by reactivation
of thrust faults and high angle normal faults. The authors
found the planation surface useful in providing information
about rates of uplift and faulting in the Apennines. From
another point of view, however, the phenomenon is
another demonstration of a widespread peneplain and
associated unconformity.
Sheth (2007) places peneplains as a central theme in his
review of the Deccan plateau in India. Sheth regards the
top of the Deccan basalt pile in the Western Ghats as a
heavily lateritised planation surface of late Cretaceous
to early Tertiary age which developed after the eruptions
during stable tectonic conditions. Laterite is a type of
tropical soil typical of semiarid regions today, characterised
by enrichment of iron oxide. Laterite is also found in places
underneath the Deccan lava flows, which themselves
have covered a number of planation surfaces. Weathering
products, called saprolites, have been found on a number
of the ancient land surfaces. More specifically, scientists
may also refer to palaeosols (fossil soils). These should
include evidence of pedological processes as well as
weathering.
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 45

It should be noted that peneplains have sometimes been
regarded as marine planation surfaces. Le Masurier &
Landis (1996) and Landis et al (2008) present evidence
for such in New Zealand and Antarctica, with major
implications for tectonic history and evolution. Garcia-
Catellanos et al (2000) explain how marine planation
surfaces in the Ardennes-Eifel region have been deformed
by Quaternary uplift related to a hotspot associated with
volcanism, as in the case of the well-known Laacher See.
Discussion and Conclusions
Clearly, large-scale geomorphology
(“megageomorphology”) has been the subject of a
number of recent studies in the Earth sciences, and is a
topic that invites, no, requires the collaboration of different
scientists with their own expertise. Regionally extensive
areas of low relief, denudational and not sedimentary
basins, occur on all the continents. Widespread
unconformities are known to occur. High level plateaus
can be mapped. The surfaces which have been exposed
to extended periods of weathering and erosion and
have not been scoured by Quaternary ice sheets, can
provide evidence in the form of palaeosols and sediments
which provide evidence to enable interpretation of their
formation, geological history, and, sometimes, dating. Even
in those regions intensively glaciated, there are occurrences
of saprolites on planation surfaces, as, for example,
demonstrated in Scandinavia by Lidmar-Bergström (1999).
The roles of weathering, fluvial and marine planation,
tectonic activity, isostasy and eustasy can be assessed in the
light of the evidence and plate tectonics. Classic localities
can be re-evaluated in relation to modern theory and
observations (Aalto, 2006).
For the geology teacher, unconformities are a fact of life,
and like book-ends in the library of Earth history. Relating
them to major erosional hiatuses leading to peneplains on
land, marginal sedimentation in epeiric seas and tectonic
activity indicates the intellectual excitement that is available
in topics like geological history or palaeogeography.
Ah, geography… What about the teacher of physical
geography and geomorphology? Can we say farewell to
gabions and groynes? Alas, geomorphology, particularly
landforms on a large scale, plays a minor role, if any, in
modern AS/A2 specifications. Judging by the two texts
referred to above, the same may be true at undergraduate
introductory level on both sides of the Atlantic. This is a
shame, because geomorphology without plate tectonics is
like biology without evolution, the Bible without Genesis,
Hamlet without the Prince.
Earth scientists need the breadth of vision of, for example,
Fairbridge & Finkl (1980). Here is a preliminary attempt to
explain the occurrence of peneplains on cratons in terms of
cycles over long time spans. Such investigations will require
interdisciplinary collaboration between geomorphologists
(typically in geography departments in Europe) and
geologists. Babault et al (2006) believe that geomorphology
needs geophysics, ‘considering both deep lithospheric and
surface processes because any surface uplift originates at
depth in the Earth’. Fairbridge’s call for a ‘meeting of the
minds’, referred to above, should not be forgotten.
Cratons are major elements of global megageomorphology,
along with their sedimentary covers. Orogenic belts of
various ages stand out as linear features on maps, and
within these there are surfaces mapable and interpretable
as peneplains. Therefore, the pattern the world’s landform
regions is far from random, but is explicable within the
theory of plate tectonics.
References
Aalto, K.R. (2006) The Klamath peneplain: a review of J S Diller’s classic
erosion surface. Geological Society of America Special Publications, 410,
pp.451-463.
Babault, J., van den Driessche, J., Bonnet, S., Castellort, S. & Crave, A.
(2005) Origin of the highly elevated Pyrenean peneplain. Tectonics, 24,
TC2010, doi:10.1029/2004TC001697.
Babault, J. (2006) Reply to comment by Yanni Gunnell and Marc Calvet on
‘‘Origin of the highly elevated Pyrenean peneplain”. Tectonics, 25 TC3004,
doi:10.1029/2005TC001922.
Babault, J., Bonnet, S., van den Driessche, J. & Crave, A. (2007) High
elevation of low-relief surfaces in mountain belts: does it equate to postorogenic
surface uplift? Terra Nova, 19, pp.272–277.
Battiau-Queney, Y. (1996) A tentative classification of paleoweathering
formations based on geomorphological criteria. Geomorphology, 16,
pp.87-102.
Brown, E.H. (1960) The Relief and Drainage of Wales. Cardiff: University of
Wales Press.
Campbell, K.E. Jr., Frailey, C.D. & Romero-Pittman, L. (2006) The Pan-
Amazonian Ucayali Peneplain, late Neogene sedimentation in Amazonia,
and the birth of the modern Amazon River system. Palaeogeography,
Palaeoclimatology, Palaeoecology, 239, pp.166-219.
Coltori, M, & Pieruccini, P. (2000) A late Lower Pliocene planation surface
across the Italian Peninsula: a key tool in neotectonic studies. Journal of
Geodynamics, 29, pp.323-328.
Coltori, M., Dramis, F. & Ollier, C.D. (2007) Planation surfaces in Northern
Ethiopia. Geomorphology, 89, pp.287-296.
Fairbridge, R.W. (1988) Cyclical patterns of exposure, weathering and
burial of cratonic surfaces, with some examples from North America and
Australia. Geografiska Annaler Series A, 70, pp.277-283.
Fairbridge, R.W. & Finkl, C.W. Jr. (1980) Cratonic erosional unconformities
and peneplains. Journal of Geology, 80, pp.69-86.
Garcia-Castellanos, D., Cloetingh, S. & van Balen, R. (2000) Modelling
the Middle Pleistocene uplift in the Ardennes-Rhenish Massif: thermomechanical
weakening under the Eifel? Global and Planetary Change, 27,
pp.39-52.
Holden, J. (2008) Physical Geography and Environment: an Introduction.
Second Edition. Harlow: Pearson Education.
Landis, C.A., Campbell, H.J., Begg, J.G., Mildenhall, D.C., Patterson, A.M.
& Trewick, S.A. (2008) The Waipounamu erosion surface: questioning the
antiquity of the New Zealand land surface and terrestrial fauna and flora.
Geological Magazine, 145, pp.173-197.
Le Masurier, W.E. & Landis. C.A. (1996) Mantle plume activity recorded
by low-relief erosion surfaces in West Antarctica and New Zealand.
Geological Society of America Bulletin, 108, pp.1450-1466.
46 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Lidmar-Bergström, K. (1999) Uplift histories revealed by landforms of the
Scandinavian domes. Geological Society of London Special Publications,
162, pp.85-91.
Linder, P. (2005) An Eocene paleodoline in the Morcles Nappe of Azeindaz
(Canton of Vaud, Switzerland). Eclogae Geologicae Helvetiae, 98, pp.51-
56.
McKnight, T.L. & Hess, D. (2008) Physical Geography: a Landscape
Appreciation. Harlow: Pearson Education.
Peulvast, J.P. & Claudino Sales, V. (2004) Stepped erosion surfaces and
palaeolandforms in the northern Brazilian “Nordeste”: constraints and
modes of morphotectonic evolution. Geomorphology, 62, pp.89-122.
Phillips, J.D. (2002) Erosion, isostatic response and the missing peneplains.
Geomorphology, 45, pp.225-241.
Sheth, H.C. (2007) Plume-related regional pre-volcanic uplift in the Deccan
Traps: absence of evidence, evidence of absence. Geological Society of
America Special Papers, 430, pp.785-813.
Sinclair, H.D., Gibson, M., Lynn, G. & Stuart, F. (2008) The Evidence for a
Pyrenean Resurrection: a response to Babault et al (2008). Basin Research
doi: 10.1111/j.1365-2117.2008.00391.x
Stanford, S.D., Ashley, G.M. & Brenner, G.J. (2001) Late Cenozoic fluvial
stratigraphy of the New Jersey Piedmont: a record of glacioeustasy,
planation, and incision on a low-relief passive margin. Journal of Geology,
109, pp.265-276.
Mark Hayward
Queen Mary’s College, Basingstoke.
mark.hayward@qmc.ac.uk
"C14 has a half life of 14 years"
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 47

A Brief History of Oz:
an Australian perspective of continental evolution
Rick Ramsdale
Abstract
Plate tectonic reconstructions use the convention of
presenting Africa as the central reference point when
illustrating plate movements. As a result it is not
easy to see what was going on in the antipodes. This
article summarises 3500 million years of continental
evolution from the point of view of Australia, a
continent with a long, eventful, and far from marginal
geological history.
Introduction
The diagrams in this article are based on recent
reconstructions, but have been redrawn to simplify general
events in a long and complex sequence. They mainly use
present day coastlines instead of shelf or ancient cratons
to aid recognition. No scales are given other than modern
Australia is around 3800km from east to west. Many useful
websites are available for anyone wanting to follow up the
various interpretations of continental movements. Some are
listed at the end.
Australia is literally an ancient land. Many of the present
day surfaces across central and Western Australia are
exhumed erosion surfaces dating back to the Mesozoic.
However, the earliest evidence for an extensively weathered
erosion surface is in Western Australia. This surface is
overlain by cherts and basalts that have been dated at 3500
million years (Ma).
Around 2900Ma the gold deposits in the Pilbara craton
were emplaced and about 2600 to 1900Ma the huge
banded iron oxide formations of the Hamersley Range
were formed. These events occurred on small, disparate
fragments of crust which were brought together by
Precambrian plate movements to form the core of the
continent we now know as Australia. The subsequent
2000Ma has also been eventful (Figure 1).
The growth of core Australia. [3500 to 1600Ma]
All continents have recognizable ancient metamorphic
cores which have younger rocks deposited on top or
‘welded on’ around their edges by orogenesis. The crust
comprising Australia can be roughly divided into two parts.
The ancient Precambrian core is in the west and Cambrian
and younger rocks on what is now the eastern seaboard.
The Tasman line is the boundary between these two
different pieces of crust (Figure 2).
Evidence comes from the radiometric ages. For example,
the Yilgarn granites are 3000 to 2600Ma. In northern
Pilbara there are sediments and basalts dated at 2800
to 2700Ma lying unconfomably over the granites and
greenstones. While in the Gawler craton there are granites,
basaltic volcanics and gneiss which were metamorphosed
between 2640 and 2300Ma. Careful study has revealed
that these pieces of crust have very different geological
histories. This indicates that not only are they very old
but also that they were separated from each other before
about 2200 Ma.
The Pilbara and Yilgarn cratons came together between
2200 and 1620Ma with orogenic events suggesting that
there were four periods of compression. As a result there
are several Precambrian basins lying close to the cratons
Figure 1 Timeline of the Evolution of Australian Continental Crust (data taken from Johnson).
48 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

The formation of Gondwana (and Laurussia) [750 to
500Ma]
During the period 750 to 500Ma plate tectonic forces
caused the ancient cratonic areas of South America and
Africa to collide with what was left of Rodinia (which by
now had been locked together for at least 600Ma – a time
span longer than the Phanerozoic). This collision formed a
new super-continent, called Gondwana made up of South
Africa, and South America in the west, and Australia,
India and Antarctica in the east (Figure 4). This huge
continent, and the evidence contained in its late Paleozoic
and Mesozoic rocks, occupies a special place in the
development of the Continental Drift/Plate Tectonics story.
Figure 2 Sketch map of the main structural elements of Australia (adapted from
Johnson and Lane). Cratons: P = Pilbara; Y = Yilgarn; G = Gawler. Amadeus,
Musgrave and Capricorn are examples of Precambrian basins and fold belts.
The Tasman Line divides Precambrian from Post Precambrian Australia.
with a roughly WNW – ESE strike (Figure 2). The Gawler
craton collided towards the end of this period, completing
the main scaffolding of Australia’s continental core as we
now know it. Just a couple of millennia later this nucleus
had been expanded by further collisions to form a supercontinent
called Rodinia.
The formation of Rodinia. [1300 to 750Ma]
When re-assembled, Rodinia comprises the Australian
cratons, most of Antarctica, India and Laurentia (which
is currently, of course, in the northern hemisphere).
Fragmentary evidence also suggests that the African
cratons of Congo, Kalahari and West Africa, plus the
Amazonian craton of South America, and possibly
fragments of China were also close by. Igneous rocks
related to these collisions have been dated at 1300 to
1100Ma.
The break-up of this supercontinent left only the India-
Australia-Antarctica ‘remnants’ of Rodinia locked together.
This fragmentation is signaled in the geological record by
basic intrusions and volcanics in places that are now as far
apart as Australia, India, Madagascar and North America.
These events have recently given radiometric dates between
830 and 795Ma indicating a significant period of basic
magmatism related to this period of continental rifting.
Meanwhile, in the northern hemisphere, other fragments
of continental crust were beginning to come together to
form a second super-continent called Laurussia. During
the Carboniferous and Permian periods this northern
super-continent, collided with the northwestern edge
of Gondwana, forming a single slab of continental crust
containing almost all of the known continental fragments
of the time. This really enormous slab of crust is called
Pangaea (Figure 5).
The formation of Pangaea [350 to 225Ma]
Such a large piece of continental crust was not able to
remain together for more than a few million years before
rifting caused fragmentation about 240Ma. Plate tectonic
forces caused the fragments to disperse around the globe
– no doubt only to collide again at some future point on
Figure 4 Gondwana at 180 Ma (adapted from Johnson). An = Antarctica;
Au = Australia; In = India; Af = Africa; Sa = South America
Figure 3 Rodinia at around 750Ma,
soon after its breakup (adapted
from Johnson). An = Antarctica;
Au = Australia; Ba = Baltica; In =
India; La = Laurentia; Si = Siberia;
TL = Tasman Line. (At this time the
Antarctic peninsular was not in its
present position, nor was the eastern
seaboard of Australia. The precise
form and extent of the northern
Indian crust is unclear, and is now
buried below the Himalaya.)
Figure 5 Pangaea around 200 Ma (loosely adapted from the uwgb website).
An = Antarctica; Au = Australia; In = India; Af = Africa; Sa = South America
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 49

its other side. The rifting marked the end of Pangaea, but
in the southern hemisphere the India-Australia-Antarctica
fragments remained together for a further 60 million years.
Building Australia East of the Tasman Line
[550 to 0Ma].
In Australia west of the Tasman Line, most of the last 500
million years have been characterised by tensional stresses.
These created subsiding basins and allowed infrequent
marine transgressions to deposit shallow water successions
unconformably over the Precambrian with shoreline and
alluvial fans along the margins of those cratons that still
remained above sea level.
However, to the east things were very different. Here,
the geological successions are indicative of a series of
destructive plate margins and suggest an intermittent
succession of arc and trench structures building
progressively further eastwards over time (Figure 6). Deep
water marine deposition began in the Cambrian, and
continued into the Ordovician allowing graptolitic muds
and turbidites to accumulate to the east of the Stavelly
andesitic arc, and shallow marine carbonates to the west.
This was terminated at 460 to 435Ma by the Benambran
orogeny. Then, slightly further eastwards the deep ocean
sediments, volcanics and turbidites of the Molong arc,
dated at 420 to 415Ma began to accumulate.
During the Devonian the Calliope Arc sequence was being
formed about 300 km east of the position of the Molong
arc deposits. These rocks indicate andesitic and rhyolitic
volcanism was occurring in a belt from Central New South
Wales, northwards to Queensland. The Tabberabberan
orogeny at 390 to 385Ma ended this cycle of
sedimentation, only for another system, the Bowen-Hunter
arc, to develop even further eastwards, characterised by
major eruptions of rhyolitic lavas and tuffs.
In this way orogenic strips were accreted onto the eastern
side of the Australian Precambrian core throughout most
of the Phanerozoic. Compression and volcanism continued
intermittently into the mid Cretaceous. However, by the
late Cretaceous crustal doming and extensional faulting
had begun, signaling the onset of widespread rifting. After
1600 million years, these southern continental slabs had
started to part-company.
During the Phanerozoic most of the western Australian
area was terrestrial with few marine transgressions, the two
most notable being in the Ordovician and the Cretaceous.
However, during the Carboniferous/Permian a period of
general uplift created a large emergent area, and it was at
this time that the classic Gondwana successions began to
be formed across the super-continent.
The Carboniferous/Permian Gondwana Succcession
[325 to 250 Ma].
In part, it was the combination of Carboniferous glacial
deposits and the overlying Permian coal seams rich in
Glossopteris flora found in now widely spaced continents
that persuaded Wegener to suggest in 1915 that a single
large southern continent had once existed and had
subsequently broken up and the fragments moved apart.
Figure 6 Periods of Andesite/Rhyolite Volcanism East of the Tasman Line (adapted
from Johnson). Along with other geological evidence, these episodes of acidic
and intermediate volcanism indicate the development of a series of destructive
plate margins. These added crustal material to Australia east of the Tasman Line
throughout the Phanerozoic.
During the Carboniferous Gondwana was close to the
South Pole and a significant glacial episode occurred
between 325 to 295Ma. Striated pavements, varved clays
and tillite deposits were left across parts of Australia, India,
Antarctica, Africa and South America. This was followed
by thick deposits of Permian coal across all these areas,
which are only preserved in basins due to post Permian
deformation and erosion. Despite being widely separated
50 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

The fracturing of Gondwana was a prolonged affair and
began in the northwest of what is now Australia in the mid
Jurassic, at about 154Ma. The rifting proceeded to unravel
roughly in an anticlockwise direction, almost like tugging
on a loose thread. The southern rifting began around
99Ma and separation from Antarctica was complete by
around 84Ma. On the east coast the fracturing rifted away
the New Zealand crustal slab and opened the Tasman and
Coral Seas in the east and north east. Then, except for the
spreading Southern Ocean Ridge, it just stopped.
Figure 7 The Indo-Australian Plate today (adapted from Johnson). Au = Australia;
In = India; PNG = Papua New Guinea; NZ = New Zealand; CS = Coral Sea;
TS = Tasman Sea
by plate movements these terrestrial Gondwana deposits
have important botanical similarities linking them together.
There are, however, significant differences between these
coal seams and the Carboniferous ones familiar to us in
Europe, apart from the obvious point that these deposits
are Permian in age.
Unlike the flora of the European coal basins, which were
spore-bearing, fern-like lycopods (e.g. Lepidodendron)
these Permian plants were gymnosperms (like Glossopteris).
These plants are akin to conifers which are modern
gymnosperms. The plant fossils from Gondwana show
strong growth rings and have leaf fossils concentrated
in certain sedimentary layers with very few in the beds
just above and below. Both features are taken to indicate
marked seasonal temperature changes from summer to
winter, meaning that these coal seams formed in temperate
climates, not tropical ones. These coal seams accumulated
as peat in high latitude basins where it was the cold
temperatures preventing complete decay of the organic
deposits, rather than burial in anoxic tropical delta-top
sediments.
During the Triassic, the Bowen orogeny deformed these
coal deposits causing folding, thrusting and uplift, allowing
erosion to separate the outcrops across the whole area of
Gondwana. Later rifting, of course, separated them even
further.
The fragmentation of Gondwana [154 to 0Ma].
The usual pattern of continental rifting and subsidence can
be recognized around the Australian coast marking the
breakup of Gondwana into its modern constituent parts,
although the rifted sections are now buried or subsided
below sea level.
In the meantime, constructive plate margins had moved
Africa and South America westwards whilst India had
sped northwards to bury its northern part deep below
the Eurasian crust in the spectacular Himalayan collision.
The opening of the Southern Ocean has allowed a cold
circumpolar current to establish itself and this has affected
the weather systems and caused Antarctica to become
colder, and the interior of Australia to become drier.
Today the Indo-Australian plate can be observed moving
northeastwards at approximately 67mm per year. On its
leading edge is a destructive margin just north of Papua
New Guinea (PNG). India is now firmly lodged on the
western side of the plate whilst on the eastern edge is a
complex plate margin through New Zealand, which leaves
part of South Island on the adjacent Pacific plate. But that
is another story.
Further reading
Johnson D. (2004) The Geology of Australia. Cambridge University Press.
Lane P. (2007) Geology of Western Australia’s National Parks: geology for
everyone. Margaret River, Western Australia
Websites
For plate reconstruction maps:
http://www.uwgb.edu/dutchs/platetec/
plhist94.htm#300my Accessed February 2010.
For plate reconstructions with inferred plate margins:
http://www.scotese.com/precambr.htm Accessed
February 2010.
For further details on Glossopterids:
http://www.ucmp.berkeley.edu/seedplants/
pteridosperms/glossopterids.html Accessed February
2010.
Rick Ramsdale
Rick.ramsdale@btinternet.com
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 51

Convoluted Structural Geology
Alan Richardson
For many years I have submitted formal comments to
the WJEC regarding their A level geology examination
papers. While I consider the system by which the
board responds to these to be deeply flawed, it
was most gratifying to see one of my repeated
observations finally bear fruit in the pages of Teaching
Earth Sciences (Vol 34; No 1), in the form of Pete
Loader’s affirmation that two limbs with different
angles of dip do not constitute an asymmetric fold.
However, I found myself less impressed with the
response of the ‘OCR AS/A2 Geology Author Team’
to Mike Brooks’ helpful observations regarding the
factual errors in their recent book. All too often I
have heard science teachers justify the dissemination
of untruths by claiming that the real explanation is
too complex for their students. There can never be
a justification for teaching students something they
will later have to unlearn. It is our job to help them
approach the truth, if necessary in small steps: we
have to present complex ideas in ways that they can
understand. If it is too complex for them to achieve
complete understanding, then we must stop at the
point beyond which comprehension falters. I hope
the following notes will clarify some aspects of fold
geometry, and offer an accessible explanation of the
development of asymmetric folds that approaches
the truth without overwhelming the average A’ level
student, yet avoids an explanation that would be
subsequently contradicted in higher level courses.
Descriptors of fold geometry are frequently confused,
even in university texts. However, there is an elegant logic
to the terminology which, if presented in a systematic
manner, makes it easy to assimilate. Figure 1 shows the
main elements of a fold. The hinge is the zone of maximum
curvature and separates two limbs. The axial plane is an
imaginary plane, which bisects the angle between the
limbs. The fold axis can be thought of as the orientation of
a line on the folded surface, which can be moved across
the surface without flexing. It is often easiest to identify it
along the hinge line (the line of maximum curvature), but
the axis is an orientation, and can be identified in other
ways (such as the intersection of bedding with axial planar
Figure 1 The structural elements of a fold.
cleavage), without the fold itself being observed: it does
not have a particular location on the fold.
Many aspects of fold geometry can be described by
reference to a small set of logical criteria. Most students
are familiar with the concepts of wavelength and
amplitude (Figure 2), and can apply them reliably. Figure 3
illustrates the concept of fold symmetry: irrespective of the
orientation of a fold, a symmetric fold has limbs of equal
length, while an asymmetric fold has limbs of different
length. To suggest otherwise would demand an explanation
of why the term ‘symmetry’ has a different definition in the
context of geology.
In many texts, folds with limbs of different dips are
erroneously defined as being asymmetric. The folds may
be symmetric or asymmetric, but the variation in limb dip
is a function of attitude. Attitude is determined by the
orientations of the axial plane and the limbs, as shown
in Figure 4. In 4a, the limbs have similar dips, so the
axial plane is more or less vertical – the fold is therefore
Figure 2 Wavelength is measured between two adjacent antiformal (or synformal)
hinges. Amplitude is half the distance between antiformal and synformal hinges,
measured at right angles at the wavelength.
52 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Figure 5 Plunge refers to the dip of the fold axis. In a non-plunging fold, it is
horizontal.
Figure 3 A symmetric fold has limbs of equal length: the fold axes are
perpendicular to the enveloping surface. In an asymmetric fold, the limbs are
unequal, and the axial planes are oblique to the enveloping surface.
Figure 4 Fold attitude is defined by the orientation of the axial plane and the
younging directions of the limbs.
Figure 6 The inter-limb angle of a non-plunging fold can be calculated by
subtracting the sum of the dips of the two limbs from 180˚.
described as ‘upright’. In 4b, the axial plane has moved
away from the upright, but the younging direction in both
limbs is upwards – the fold is therefore said to be ‘inclined’.
4c shows a fold in which the axial plane is so inclined that
the younging direction in one limb is now downwards,
allowing the fold to be defined as ‘overturned’. In 4d,
the axial plane is more or less horizontal and the fold is
‘recumbent’. It is the inclined fold that is most frequently
mis-identified as asymmetric.
Plunge refers to the inclination of the fold axis: a plunging
fold has an inclined axis (Figure 5b); if the axis is horizontal,
the fold is described as non-plunging (Figure 5a). The
attitude of the axial plane is irrelevant.
The inter-limb angle, as the name implies, is the angle
between the limbs. In a non-plunging fold, it can be
calculated by adding together the dips of the two limbs,
and subtracting them from 180˚: the remainder is the interlimb
angle, as shown in Figure 6. This gives 5 categories of
fold (Figure 7):
• gentle folds have an inter-limb angle of
120˚ – 180˚.
• open folds, in which the inter-limb angle is
70˚ – 120˚.
Figure 7 Five categories of fold can be recognised based in inter-limb angles.
• close folds with an inter-limb angle of 30˚ – 70˚.
• tight, in which the onter-limb angle is less than 30˚
• isoclinal (literally, “equal dip”) if the limbs are
approximately parallel.
In some systems of classification, the ‘gentle’ and ‘open’
categories are merged, as are the ‘closed’ and ‘tight’
for inter-limb angles greater than, and less than 90˚
respectively.
Figure 8 illustrates the difference between cylindrical folds,
which are persistent and have straight hinge lines (8a), and
non-cylindrical folds, which are impersistent (8b).
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 53

Figure 10 Antiforms and synforms can be identified from dip information alone.
Figure 8 Cylindrical folds have straight hinges, while those of non-cylindrical folds
are not.
If two adjacent folded surfaces have the same shape, the
fold they enclose is a similar fold: the layer will be thicker
in the hinge than in the limbs (Figure 9a). If the distance
between the two surfaces remains constant (in other words,
the thickness of the layer does not vary) the deformed layer
constitutes a parallel fold (Figure 9b). The deformation of a
sequence of rocks displaying a range of competencies will
generate parallel folds in the competent layers, and similar
folds in the incompetent layers (Figure 9c).
Upward-arching (or upward-closing) folds are antiforms;
those which arch or close downwards are synforms. In the
absence of way-up criteria, folds cannot be classified as
anticlines or synclines. In the former, the oldest rocks are
found in the core of the fold (whether it closes upwards
or downwards); in the latter, the youngest rocks are in
the fold core. Figure 10 illustrates the dip information by
which antiforms and synforms are identified. Figures 11a
and 11b show the criteria by which anticlines and synclines
are defined – way-up criteria are used to identify the
younging directions shown on the diagrams. Both anticlines
and synclines can be antiformal or synformal – the two
pairs of terms are not interchangeable. Neutral folds
close sideways, so they cannot be defined as antiforms or
Figure 11a Synclines and anticlines in a normal sequence.
Figure 11b Synclines and anticlines in an inverted sequence.
synforms. However, their attitude does not preclude their
identification as anticlines or synclines.
Figure 9 The inner and outer surfaces of a similar fold have the same curvature, and
the thickness of the layer increases in the hinge. In a parallel fold, the curvature of
the inner surface is much tighter than that of the outer, and the layer maintains the
same thickness at all points.
The crest of a fold is the highest part of an antiform; the
trough is the lowest part of a synform. If the folds are
upright, these are likely to coincide with the fold hinges,
however, in folds with other attitudes they may not
(Figure 12).
54 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

The foregoing is a summary of terms that can be used to
describe and record folds. Once students are familiar with
the ways in which folds can vary, it is possible to consider
their interpretation in terms of mechanisms of formation.
In this article, I would just like to deal with the topical
problem of explaining the development of symmetric and
asymmetric folds, which the OCR AS/A2 Geology Author
Team seem to suggest is too complicated to be explained to
A level students, without employing a fallacy. The following
is not a full explanation, and will leave the able student
asking more questions, but it takes a step in the direction
of the truth and will not have to be unlearnt if the student
progresses to a higher level of study.
In each of the following examples, only the maximum
principal stress axis (σ max
) is shown. In the first scenario,
the three layers have the same competence (ductility) and
lie at right angles to the axis of compression. The layers all
get thinner, and extend in a direction at right angles to this
axis, however, no folds develop (Figure 13a).
In the second case, the axis of compression lies parallel to
the layers, but once again, all three layers are ductile, and
have identical physical properties. Consequently, they all
behave in exactly the same way: thickening and shortening
without folds developing (Figure 13b).
If a layer cannot accommodate the shortening by a
consequent thickening, it will buckle. In the third situation,
the axis of compression is parallel to the layers, and leads to
the development of symmetric folds Figure 13c).
However, if the axis of compression is oblique to the
layering, as in the fourth case, the resulting folds will be
asymmetric (13d).
Figure 12 The locations of crests, troughs and hinges in an overturned antiform and
corresponding synform.
In summary: if the axis of compression is more or less
perpendicular to the layers, shortening will not produce
folds. If it is parallel to the layers, shortening generates
symmetric folds. If it is oblique to the layers, the result will
be asymmetric folds. At A level, I do not think it needs to
be any more difficult than that. Nevertheless, this limited
explanation can be used to explain why the two limbs of a
developing fold may develop parasitic folds with opposite
senses of asymmetry: the erroneous description of the
development of asymmetry offered by the OCR team offers
no help in explaining the phenomenon.
If an individual teacher conveys a misconception to a class,
it disadvantages a few individuals. When an author does
the same, more students are exposed to the error, but the
teacher can overcome it through lectures or handouts.
However, when examiners publish misconceptions in
textbooks, specifications and mark schemes, teachers
are faced with a dilemma: do they teach the untruths,
knowing that they will be rewarded in the exam, or do they
teach the truth and run the risk of their students being
penalised when the examiners’ mark scheme offers no
credit for the correct responses? Ultimately it is up to all
teachers of Geology to feedback to the examiners through
formal channels whenever errors are identified. Equally it
is the professional responsibility of examination boards to
respond formally in such a way that all teachers are aware
of the arguments and resolutions, so that no candidates are
disadvantaged.
Figure 13 The ways in which layered sequences respond to compression are
controlled by many variables. The development of asymmetric folds can be
explained very simply in terms of the axis of compression being oblique to the
deforming layers.
Alan Richardson
as.richardson@virgin.net
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 55

Somerset Earth Science Centre Opens
Martin Whiteley
The new Somerset Earth Science Centre
was formally opened in July 2009 by Her
Royal Highness, The Princess Royal. The
centre, which is adjacent to Moons Hill
Quarry in Stoke St Michael, near Shepton
Mallet, provides learning experiences for
school children and students of all ages
through classroom activities and field
work.
Funded and managed by the Mendip Quarry
Producers (MQP), an association of the
leading quarrying companies in Somerset, the
purpose-built centre offers a range of flexible,
curriculum-led topics for students in Key
Stages 1 to 4 and those in further and higher
education. Topics depend on the age of pupil,
but include all aspects of quarrying, geological sciences,
river studies, environmental impact management and
sustainable development. Students are based at the centre,
with field work opportunities in the adjacent lake and
woodland, and excursions to local quarries and nationally
important geological sites such as Tedbury Camp Quarry
and the De La Beche unconformity in nearby Vallis Vale.
The Somerset Earth Science Centre has evolved from the
MQP’s East Mendip Study Centre which for 12 years was
located next to Hanson’s Whatley Quarry. Since it opened
in 1997, the centre received over 4,000 visitors a year from
some 50 different schools, colleges, organisations and
clubs.
In 2005 it became clear that a major upgrade to the
facilities, or a new building, was needed to guarantee its
future. The MQP secured a grant from Somerset Minerals
Forum to consider the options and in due course a
decision was made to build a new facility at Moons Hill.
Capital funding was secured primarily from the MQP, with
contributions from Somerset County Council’s Aggregates
Levy Sustainability Fund and other sponsors. The centre is
managed by a charitable company with directors appointed
from the MQP and the District Council.
HRH The Princess Royal opening the new Somerset Earth Science Centre on 29th July 2009.
The new £600,000 single-storey building has a large
classroom and display area, staff office, changing rooms
and toilets. Some of the internal walls incorporate local
building stones and the attractive external façade is faced
with Lower Lias limestone. The building is designed to be
carbon neutral and features a number of energy saving
initiatives, including its own wind-power turbine and
ground source heat pumps.
The Somerset Earth Science Centre will continue to
provide all educational activities free of charge and you are
encouraged to make use of this unique facility. For further
information and to discuss how the centre can help your
teaching requirements, talk to either Gill Odolphie or Mary
May.
Website: www.earthsciencecentre.org.uk
Email: info@earthsciencecentre.org.uk
Phone: 01749 840156
Martin Whiteley
mjwhiteley@yahoo.co.uk
56 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Reviews
The Control of Nature
John McPhee
Farrar, Straus & Giroux. 1990
ISBN13: 978-0-374-52259-9 $9.46
First published in
1989, this book
may not be a new
addition to Earth
Science teachers’
bookshelves but
is nevertheless an
engaging book
that has charm
and relevance to
those interested
in the engineering
challenges faced
in tackling some
of man’s biggest
battles with nature.
It is of particular interest to those following the WJEC
AS Geology specification (GL3 – Geology & the Human
Environment).
More of an historical account of events than a geological
one, McPhee details the strategies and tactics through
which people attempt to control nature and carries us to
the front lines of the still-raging battle between man and
nature.
The book focuses on three key locations : Louisiana, on
the lower Mississippi River, USA, where even today
engineers are fighting a continuing battle with the river
which threatens to follow a new route to the sea and cut
off New Orleans and Baton Rouge from the rest of the
United States; Iceland where inhabitants confront the red
hot lava of the 1973 volcanic eruption in an attempt to
save the crucial harbour of Heimaey, Westmann Islands;
and Los Angeles, USA where basins are built to catch
devastating debris flows from the San Gabriel Mountains.
Unflinchingly honest, yet unashamedly editorial, the three
long stories (or chapters) pit relentless nature against
mankind in a clash of wills reminiscent of Greek tragedy.
What emerges are tales of determination, folly and grim
triumph; a modern mythology where nature supplies the
gods and man plays himself at his imperfect best.
If you have been lucky enough to visit the Westmann
Islands, Iceland yourself, Chapter Two is perhaps of most
interest. Here, McPhee brings to life the 1973 eruption and
the people involved in the taming of the volcano – Eldfell.
There are vivid comparisons made to Vesuvius in AD79,
Hawaiian eruptions and the controlled bombing of Etna,
Sicily by the military in an attempt to divert the devastating
lava flows and save land and lives. McPhee’s research
involves eye witness accounts and key quotes from those
involved in the battle at the time. The stories are well told
and bear witness to the ultimate resilience of the people of
the Westmann Islands.
McPhee doesn’t just write about science, he writes
about people who apply and sometimes defy science in
their struggle to control nature and protect themselves
from the inevitable. Blending the best of Sunday-paper
feature writing with the drama and insight of a novelist,
he has produced a fascinating account of the struggle of
the engineers in New Orleans, the Icelandic people on
Heimaey and the head-in-the-sand mentality of Southern
Californians when it comes to mudslides.
I would recommend the book to any students of Geology,
or indeed Geography but also to Earth Science teachers to
gain a further insight into some of the major geological/
historic events of the last 40 years. My only real criticism of
the book is that whilst there are illustrations, there are no
maps (or diagrams) in the book to put the locations into
a geographical context and readers would have benefited
greatly from such inclusions.
Dawn Windley
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 57

Death of an Ocean –
A Geological Borders Ballad
Euan Clarkson & Brian Upton
Dunedin 2009
ISBN 9781906716028 £25.00
Put your feet up,
have a glass ready,
and thoroughly
enjoy a book which
is easy to read
while also being
informative. Do
we need anything
else on Iapetus
and Caledonian
Mountains? Yes
we need this book
that gives a concise
account with
reference to South
East Scotland (an
area east of the Clyde valley and M74).
The experienced authors Euan Clarkson, a retired professor
of palaeontology, and Brian Upton a retired professor of
petrology write about the demise of the Iapetus Ocean and
the subsequent Caledonian Mountain Chain, followed by
the changes in environment during Scotland’s northward
drift. The book also includes information on graptolite
ecosystems, plus occasional references to pioneers of
geology who worked in this region. Reference is made to
James Hutton (with good description of Sicar Point) and
Arthur Holmes both of whom are referred to as the great
‘Time Lords’- move over Dr Who!
The target audience is everyone from the amateur
geologists, AS/A2 students to the professional geologist.
For the student it includes many concise explanations of
geological phenomena for example radiometric dating.
The book is not intended to be a comprehensive field guide
although all sites referred to are those that have been used
for teaching students e.g. the famous graptolite site at
Dobb’s Lynn which still looks similar to when I visited it over
40 years ago, but with this new found knowledge I can’t
wait to go back – (and I also hope the waffle house is still
there in Moffat).
The illustrations and photographs add to the text although
some photos could do with more annotation e.g. how easy
is it for an amateur to distinguish the fault in photograph
5.2 of the folds and faults at Pettico Wick.
It would be useful to see a grid reference given to the
key localities and then listed in a page at the back of the
book. This would help anyone who wished to visit this
region to locate the sites with more precision, compared
with following a description such as ‘exposures of pillow
lava near Noble House, SE of A701 between Leadburn and
Romanno Bridge’.
These are minor criticisms as this book is one of the
best geological reads I have encountered. Some of my
geological knowledge has been reinforced, but I have also
learnt many new things. But more than this, reading the
book has given me a desire to revisit this area of Scotland
(which is well known as ‘Bill McClaren Country’ in the
world of rugby union) but will be known from now on as
the classical geological region displaying evidence for the
‘Death of an Ocean’
This is a book that brings the region alive, the authors
are to be complimented on their style of writing and
the content. I thoroughly recommend this book to all
geologists, those starting on the path or those coming
to the end. This book is a template for anyone else who
wishes to write about the geology of any other region of
the British Isles. Finally, as someone who has also been
involved with folk music, this book is a ‘ballad’ which will
stand the ‘sands of time’.
Ray Humphries
Deep Time Cabaret:
An Earth Science Drama
Time present and time past
Are both present in time future
And time future contained in time
past.
T S Elliot: Four Quartets Burnt Norman
I spent last Halloween watching a new show with an Earth
science theme: Deep Time Cabaret. The production was
at the Harlequin Theatre in Northwich, a town famed for
its exploitation of the Earth’s resources, namely salt, and
a town that has been blighted by the exploitation of the
Earth’s resources. Recently millions of pounds have been
spent in Northwich grouting up the old flooded salt mines
as both mines and town were on the verge of collapse.
The play had opened in another mining part of Britain, the
Forest of Dean; the first performance was underground in
the Clearwell Caverns, a former haematite mine, followed
by a performance at the Science Festival in Manchester.
58 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

The starting point of the Deep Time Cabaret (written
and directed by Bob Frith of the Horse and Bamboo
Company) was the exploitation of the geological resources
of Rossendale – sandstone quarrying and coal mining.
The Deep Time Cabaret links into the myths and legends
of miners and quarrymen – spirits, ghosts and grey ladies
seen in mines. Similar mining and quarrying legends are
common across the country from Rossendale to the Forest
of Dean. These myths and stories are also in the Tales
of Hoffman – the Cabaret uses a film excerpt by Tracey
Holland to pick up this theme, with fleeting glimpses of a
grey shadowy figure, or was it a wolf, flitting through the
murky mine passages.
The overall theme that runs through the Deep Time
Cabaret is time; linking the past to the future and the
future to the past. Showing that the exploitation of Earth’s
resources is limited by time – the Earth resources are finite.
The set is a wooden framework of trestles and ladders
up and across the stage, with objects, baskets, lamps
and tools hanging down. Like the wooden supports of
an underground mine – reminiscent of the old mining
photos of the Cornish mines or my trips underground in
the Florence (haematite) Mine at Egremont, west Cumbria,
the Bronze Age copper workings at the Great Orme,
Llandudno, the Ecton Copper Mines of Derbyshire and the
Snailbeach lead and zinc mines of Shropshire.
The Deep Time Cabaret opens with a steady beat of piano
music, with the occasional sound of far off digging and
hacking of rocks, chanting songs in foreign tongues or
strong accents. Could these be the lost voices of former
miners or miners working just around the corner of the
mine passages? As the light dimmed two men with
head lamps appeared, then total darkness. The miners
demonstrated not seeing their hands in front their faces.
The same darkness as underground at Egremont, Ecton
and Snailbeach when we were all told to turn off our lamps
– very black, very quiet – a sense of waiting and listening,
hearing the weight of the rocks above our heads.
A person appeared holding a candle in their mouth – again
an image seen on the old Cornish mining photos. The
underground theme is well set, as the miners climb up and
through and over the wooden framework in the dark with
haulage noises from a far off mine shaft. This mining theme
particularly appeals to me as an ex-coal geologist and to my
delight the mine surveyors then appeared with a selection
of instruments, getting the measure of the underground
Earth.
The Cabaret was divided into acts, introduced with the use
of a blackboard. The act titled ‘Deep Time Lecture’ really
appealed to me, with its very effective use of mixed media
from songs to films to the disembodied ‘Stephen Hawking’
voice of science explaining seriously the slow speed of
continent movement. Again the hand motif occurs, this
time to demonstrate the rate of growth of finger nails and
the rate of plate movement.
This is really the first introduction to the ‘Deep Time’
concept in the Cabaret, which is developed again to my
liking with the use of food and geological processes.
While one actor fills bags with slices of different types of
bread and cakes, another fixes the bags to a cable across
the stage and hauls them like mine tubs across the stage,
where they are received, emptied and the bread and
cakes are stacked layer by layer in a transparent container
– repeated time after time. Eventually the layers are
compressed. The repetition simulates the slowness of the
transport and deposition of layers of sediment and the
slowness of time it takes to compress layers of sediments
to layers of rock. The stacking and compressing of layers
goes on all the while to the sound track of the ‘Stephen
Hawking’ voice of serious science repeating and repeating
..........‘ millions of years’ .........’ gradual compression’.
The myths and legends of the mine workers’ lives
underground are portrayed very effectively with Punch
and Judy type puppets and shadow puppets accompanied
by a drippy, drip, drip of water sound track. The mining
machinery shadow show has a definite Heath Robinson feel
about it. The theme the Cabaret now introduced appears
to be how Mother Earth or the spirit of the mines agrees
to the exploitation of the heart and wealth of the Earth,
but at a price. As if the wealth of the Earth is on loan. I
assume implying how mined Earth resources are finite
– not renewable, with the message that the price of past
excavation and exploitation is paid in the future.
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 59

The Deep Time Cabaret then changes tack to deep space
and to even deeper time with the stars, the constellations
and the universe interwoven with mythology of the Greek
gods – harder for myself to grasp as I’m definitely a downto-earth
geologist and preferably an under-the-earth
geologist, rather than away with the stars. But the use of
the woman mine worker’s white shawl as the projection
screen for the images of the Milky Way was fascinating.
I went to see the Deep Time Cabaret with no idea of what
it would offer and came away delighted at the mining links,
the sedimentary bread and cake layers and the songs, but
surprised at the Lancashire clog dance. I do recommend
you to go and see the show or welcome it into your school.
Deep Time Cabaret is certainly a new way to view scientific
concepts and definitely sparks cross-curriculum discussion
on science, myths, our mining heritage, all set against the
beating heart of the Earth and the ticking clock of Deep
Time measuring time present, time past and time future.
Deep Time Cabaret is supported by the Heritage Lottery
Fund, Groundwork Pennine Lancashire and the Arts Council
England. Web materials are available for schools as an
education packet from http://www.horseandbamboo.
org/deeptimecabaret.htm
Ros Todhunter
rostodhunter@aol.com
Deserts and desert
environments
Laity, J.
Chichester: Wiley-Blackwell. 2008. 342 + xiii pages.
ISBN: 978-1-57718-033-3. £29.99
Western society has been interested in the warm deserts of
the world ever since the days of 18th Century exploration,
yet the focus of
this interest has
changed over
time. The era
of exploration,
colonisation and
reconnaissance
mapping
has passed,
but deserts
increasingly have
become a focus
of scientific and
applied studies
owing to their
vast areal extent, ever-growing human populations, the
significant resource potential of many areas, and issues
such as land degradation and biodiversity loss.
The book Deserts and Desert Environments by Laity
reflects this growing interest, and forms part of
Wiley-Blackwell’s Environmental Systems and Global
Change Series, which is aimed primarily at advanced
undergraduates and graduates taking degree courses in
the geosciences and cognate disciplines. In line with the
ethos of this series, Laity aims to portray an understanding
of the desert environment as a whole – its climate,
hydrology, geomorphology, and basic biology – and to
illustrate human interactions and environmental concerns.
Nevertheless, the emphasis throughout the book is on
geomorphic systems.
Chapter 1 starts by defining the desert system, including
its physical and biological components, and outlines how
desert characteristics vary regionally and globally, and how
they have changed over time. Chapter 2 expands on this
theme of global variation by outlining the major deserts of
the world, and illustrating their great diversity. Subsequent
chapters examine the physical components of deserts
in more detail: the climatic and hydrologic frameworks
(Chapters 3 and 4); past and present lake systems (Chapter
5); weathering and hillslope systems (Chapter 6); soils and
landsurface characteristics (Chapter 7); the role of water as
a landforming agent (Chapter 8) and aeolian processes and
landforms, including sand transport and dune formation
(Chapter 9) and erosive landforms and dust transport
(Chapter 10).
Thus far, the book’s content is similar to many other desert
geomorphology textbooks, but where it differs is in its
more explicit consideration of the nature, environmental
requirements, and geomorphic impacts of desert plant and
animal communities (Chapters 11 and 12). The coverage
is brief, but reflects a growing recognition of the need to
link atmospheric, hydrospheric, geospheric and biospheric
processes if we are to gain an integrated understanding
of desert system dynamics. Throughout the book there
are references to human-environment interactions and
environmental concerns, and Chapter 13 considers human
impacts more explicitly, particularly in the context of the
oft-used but contested term ‘desertification’.
The book adopts a global perspective, with examples and
case studies drawn from many desert areas of the world.
The academic literature on deserts is well represented
and reasonably up-to-date, especially with respect to
geomorphology: an extensive reference list (35 pages)
contains a number of ‘old classics’ and a smattering of
more recent studies from this millennium, including several
with a 2007 publication date.
60 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

With an introductory textbook of this nature, however,
coverage of some topics inevitably is unclear, uneven or
patchy, and there are some debatable statements. For
instance, terms such as ‘deserts’, ‘semi deserts’, ‘arid’,
‘hyper arid’ ‘semiarid’, ‘dry-sub humid’, ‘dry lands’, ‘true
deserts’ and ‘desert fringes’ are all introduced within the
first 12 lines of Chapter 1 but the definitions of – and
differences and similarities between – these related
terms are never made clear, and what little explanation
is provided is likely to confuse rather than clarify. This
lack of clarity with regard to these key terms persists
throughout the book, and is particularly acute when the
first figure seems to use a different definition of ‘desert’
than is given in the first paragraph of Chapter 2, while
the figures in Chapter 2 use yet another classification
and map ‘deserts’ and ‘arid regions’ separately. In terms
of the balance of topic coverage, around 51 pages are
devoted to aeolian processes and landforms (Chapters 9
and 10), but river processes and landforms are covered
in only around 20 pages (Chapters 4 and 8), despite the
fact that rivers are a more important geomorphic agent
than the wind in many deserts. In examining water as a
geomorphic agent, the role of groundwater sapping in
slope and valley development is stressed (Chapter 8), but
there is no acknowledgement of recent studies that have
challenged this interpretation. Wetlands are given relatively
short shrift, despite the fact that collectively they can fulfill
important biological, sedimentological, and hydrochemical
functions in many deserts, although to some extent this is
counterbalanced by the emphasis on lake systems (Chapter
5). The role of fire – increasingly recognised as an important
agent of physical and biological change in deserts – is
mentioned only briefly in a few places (the term ‘fire’ does
not even appear in the index).
images don’t really add anything further in the way of
understanding. Even where scale bars have been included
in photographs of features at ground level, the units on
the scale bars are not obvious or are not explained in the
captions, again making them very hard to interpret. This is
a shame, for otherwise the layout, typeface and production
of the book are very good.
Now for the litmus test: will I be recommending this
book for my own advanced undergraduate class in desert
geomorphology or for my postgraduate students? The
answer is ‘yes’. Despite its shortcomings, it contains
enough information and different perspectives to be
suggested reading alongside other desert geomorphology
textbooks. At the very least, I will be recommending that
the book finds its way onto the library shelves.
Stephen Tooth
Rivers Basin Dynamics and Hydrology Research Group
Aberystwyth University
Dorset and East Devon
landscape and geology
Malcolm Hart.
The Crowood Press. 2009. 240 pages
ISBN: 978-1847970893 Softback £18.99,
These sorts of issues are by no means unique to this
desert book, and on the whole it does a good job in
conveying the distinctiveness and diversity of deserts and
desert research. The most disappointing aspect, however,
is undoubtedly the quality of some of the illustrations.
The preface (p.xiii) claims that: “One of the goals of this
book is to provide the reader with imagery designed to
enhance their understanding of global deserts …. [and]
illustrate the spatial dimensions and regional topography
of deserts”. While the book does include a large number
of maps, ground-level and aerial photographs, and orbital
(satellite) imagery, some of which are annotated, many of
the aerial photographs and orbital images are completely
lacking scales or coordinate systems. For those readers
unfamiliar with deserts, these images will be very hard to
interpret without scales, and they cannot be easily related
to other sources of desert imagery (e.g. on Google Earth)
without coordinates. Some black-and-white images are
also reproduced as colour plates in the centre of the book,
yet without the requisite scales and coordinates, the colour
This is a very welcome addition to the growing number
of guides to the Jurassic Coast of East Devon and Dorset.
Written by Malcolm Hart, Professor of Micropalaeontology
at the University of Plymouth, the book is a winning
combination of academic rigour and well illustrated travel
guide. It will prove an invaluable resource for Geography,
Geology, Archaeology and Environmental Science teachers
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 61

when planning field visits to the area as it covers not only
the well known, well trodden locations but a large number
that are off the beaten track but equally important, well
explained and grid referenced.
The introduction addresses the wider geological setting
of the region in terms of earth systems processes with
reference to tectonics, climate change, ocean/atmospheric
processes and the evolution of life. The structural controls
on the formation of the Wessex Basin are explained in a
clear and concise style which will be of particular interest to
geologists.
The book is generously illustrated with over 240 colour
photographs plus a number useful maps and diagrams
to guide the reader through the myriad of sites of
interest along this spectacular stretch of coastline. The
book is divided into three main sections, the first deals
with the geology and geomorphology of the region
and has considerable detail on the stratigraphical and
palaeontological highlights of the area. The second explains
and evaluates the impact of man on the landscape from the
earliest settlers through Roman times to the impact of the
extractive industry and the present day. Finally, conservation
issues and the future of the area both in the short term
and the much longer geological term are considered in a
scientific and sober fashion.
There is a useful glossary of terms and a further reading list
at the end which complements the informative and well
written text. On balance, this is an excellent introduction to
area and probably the most comprehensive guide published
to-date. In short, an essential purchase.
Ian Kenyon,
Truro School
Earth’s Climate – Past and
Future 2nd Edition
William F Ruddiman
W.H.Freeman & Company 2007 388 pages
ISBN 0-7167-8490-4 Paperback £58.99
This book leaves no stone unturned in attempting to
identify the possible causes of climate change through a
range of scales from the geological past into the future.
Topics are covered very thoroughly in a detailed text which
is supported by numerous colour images. A well structured
book it is subdivided into 5 main sections; framework of
Climate Science, Tectonic-scale Climate Change, Orbital-
Scale Climate Change, Deglacial Climate Change, Historical
and Future Change which are then further sub-divided into
a total of 19 chapters. For teachers wishing to use the book
as the basis for an entire course there are course outlines
allocating lectures to the chapters, all based upon the US
Semester system.
Although the language and detail would, in my opinion,
be too challenging for even the most able A level student
the book provides a valuable source of material for teachers
delivering climate change in A level Geology, Geography
or Science. Even then some may find that they simply dip
in and out for specific images and data. Several of the
chapters can, however, be directly related to current A Level
Geology specifications. Each chapter contains a series of
Review Questions and reference to additional resources.
Following 14 chapters on the physical causes of climate
change linked to orbital changes, plate tectonics and
astronomical control the final 5 chapters assess the past,
present and future role of humans in altering the climate of
our planet.
62 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Earth’s Climate provides a multidisciplinary approach which
in the latter stages develops a clear chronological sequence
of recent change. The book concludes with useful
appendices on the Isotopes of Oxygen and Carbon and a
particularly useful glossary.
I would certainly consider this book as a one off copy for
the library to support the development of resources but as
a text book for student use it is both aimed at, and is more
appropriate for, degree level specialists.
Stuart Hitch
Department of Geography and Geology
King Edward VI Grammar School
Chelmsford
Essex CM1 3SX
Journeys from the Centre of
the Earth:
How Geology shaped Civilisation
Iain Stewart.
Century 2004 Hardcover: 288 pages
ISBN-13: 978-1844138135. £10.50
Four of the most impressive Wonders of the Ancient World
were destroyed by earthquakes (being the Colossus of
Rhodes, the Temple of Zeus, the Temple of Artemis and the
Mausoleum of Halicarnassus), which shows the power that
the planet can bring to bear against humanity. It is clear
that however strong a man-made building is, it is always at
risk from the ever-moving earth. The power of the earth to
affect civilisation is the main subject of this book.
Earth’s geology has had a constant effect on the various
civilisations that have colonised its surface since the end
of the last ice age (c. 12,000 years ago). This book looks
at history through the eyes of a geologist, from the
glorious colours of the Lascaux Caves (painted c. 15,000
years ago) through to the modern day, though the book
is centred about the Mediterranean civilisations from the
Old Kingdom Egyptians in around 3000BC to near the end
of the Roman Empire in around AD 500. It examines the
geology and history of the Mediterranean from Gibraltar in
the West to the Black Sea and the Dead Sea in the East. As
Stewart says, the period since 1784 has been designated by
some, ‘The Human Age’. This was the first time that man
made more of a difference to the atmosphere than the
natural outpourings of gas (from volcanoes/cows etc).
It is important to note that geology does not only effect
civilisation through cataclysmic events. As the sands of time
slowly fall, a gradual change of climate can spell doom for
a flourishing society. Over the last 10,000 years, Stewart
tells us the amount of rainfall in the various countries
around the Mediterranean has varied massively. In less than
1500 years (2200BC-700BC), the Greeks went from trying
to conserve ever last drop of rain and river water in huge
underground cisterns, to flood control as the rivers swelled
and they could not control the sheer volume of water
passing through them.
Everyone knows that geography has a huge effect on
history (hence why the French study them as one subject
– histoire-géo), but the aim of this book is to show that
geology has just as significant an effect. While you may
want to build a city (e.g. Rome, which was built on top of
seven hills) or a fort on top of a hill (geography), you also
need to make sure that the water table is high and the
rocks are porous so that you can get enough water through
wells to last out a siege (geology).
While being a serious piece of academic writing, the main
purpose of this book is to popularise geology. There are
no footnotes or endnotes and annoyingly no index. This
does make finding anything in the book rather difficult.
However, the photographs are amazing and many of the
diagrams (drawn by Stewart himself) are very useful indeed.
A few more maps might have been helpful to see an
overview of the area in question, but it is all laudable work.
This book would certainly be of use to anyone doing A
level or above in Geology, History (mostly Ancient History
rather than Modern History), Archaeology, Geography,
Classical Civilisation or Sociology. I found the book to be a
tremendous read as well as being highly informative, and
would thoroughly recommend it to anyone with an interest
in the physical world and its effect on society.
Benedict Sharrock,
A level student, Geology Dept. St. Bede’s College,
Manchester
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Introduction to paleobiology
and the fossil record.
M.J. Benton and D.A.T. Harper.
Wiley-Blackwell, Oxford. 2009.
ISBN 978-1-4051-8646-9. Paperback. £34.50.
Companion website:
http://www.blackwellpublishing.com/paleobiology
Each fossil group is covered in adequate detail – it is of
interest to see that the graptolites occupy 13 pages, by
comparison with the 26 (smaller) pages in Clarkson’s
textbook. Indeed, the book could well be used beyond
second year level. Illustrations, both line drawings and
photographs, are mostly clear. The text is always readable,
and for those chapters for which the reviewer has some
experience, commendably accurate. It may be noted that
individual chapters have been read by experts in that field.
The general chapters form a major part of the book,
and could almost form a separate textbook in their own
right. Fossils in time and space includes a good account
of biostratigraphy, and the use of fossils, leading to types
of zonation. It also includes a description of sequence
stratigraphy, leading to the recognition of cycles of
astronomical change, and cyclostratigraphy. The chapter
on taphonomy is an excellent account of the physical
and chemical changes taking place after death, with the
illustrations of the muscle fibres of a Jurassic horseshoe
crab the highlight. I particularly liked the quotation from
Frankenstein which prefaced this chapter!
Palaeontology is very well served at the present, by
textbooks ranging from those suitable for school use (such
as Milsom and Rigby’s Fossils at a glance) to advanced
textbooks (e.g. Clarkson’s Invertebrate palaeontology
and evolution). However, not all cover the whole field of
palaeontology, which Introduction to palaeobiology and
the fossil record does. The book is intended for first- and
second-year university geologists and biologists.
In total, this book is an incredible tour-de-force, imparting
both so much knowledge, and the tools with which to
examine and interpret finds. Its breadth of coverage
would aptly entitle it to be called an encyclopaedia of
palaeontology, and as such, will provide almost all a student
would require for a palaeontology course, and at its price it
is a bargain. It can be enthusiastically recommended.
Denis Bates
Aberystwyth
The field is covered in twenty chapters, the first seven
being on general topics: Paleontology as a science
(American spelling is used throughout); Fossils in time and
space; Taphonomy and the quality of the fossil record;
Paleoecology and paleoclimates; Macroevolution and the
history of life; Fossil form and function; Mass extinctions
and biodiversity loss. A chapter on the origin of life leads
to eleven chapters on specific fossil groups, including
fossil plants and trace fossils. A final chapter covers the
diversification of life. In addition to the written book,
there is also a companion resources website. A series of
special topic boxes are scattered throughout the text: Hot
topics/debates; Paleobiological tool; Exceptional and new
discoveries; Quantitative methods; Cladogram/classification.
For each chapter, there are review questions, a reading list,
and a further list of references (publications are given up to
2008).
64 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Excursion Guide to the
Geology of East Sutherland
and Caithness (Second
Edition)
Edited by Nigel Trewin and Andrew Hurst
Publisher Dunedin in association with Aberdeen
Geological Society. 2009
ISBN 13: 9781906716011. Price: £14.99
through fluvial, aeolian and playa lake deposits
to the deep lake laminitis with the world famous
fossil fish fauna.
• The Jurassic succession adjacent to Helmsdale fault
which is demonstrated with particular reference
to the famous Helmsdale Boulder Beds deposited
beside an active submarine fault scarp, and the
Lower Jurassic succession which has an affinity with
the Beatrice Oilfield.
All the excursions are colour coded for easy reference, well
planned and informative Each begins with the purpose for
that excursion; clear information on access; other general
information; tides; length of time needed to complete the
excursion and even the best time of the year to go.
Each itinerary is easy to follow with all localities located
using grid references. The itineraries are illustrated with
clear maps and diagrams and fabulous photographs. If you
sat down and looked only at the photographs you will learn
a great deal about sedimentary rocks and structures.
If you like fossils this book has superb cartoon diagrams
to show how the flora and fauna relate to different
environments e.g. in relation to the Helmsdale Boulder
Beds, plus other information on trace fossils in the Ousdale
Mudstones, and fish in the Achannaras Beds.
It would take you at least a week to follow all the
excursions which vary from a 1-2 hours itinerary to whole
day excursions. However, don’t worry if the weather is
unsuitable, the letter H on the excursion map indicates a
convenient hostelry!
Why did I select this for my first book review? Immediately I
was impressed by the quality of the photographs. Secondly
it is an area of Scotland I am unfamiliar with and thought it
was time to brush up on my knowledge.
I found this book to be a well illustrated (and not just
the photographs) and well informed excursion guide
that provides a good overview to the geology of North
East Scotland. The book begins with a comprehensive
account of the geological history of the area (35 pages)
followed by guides to six geological excursions Golspie;
Borra; Kintradwell to Helmsdale; Ousdale; Caithness and
Kildonna.
Both editors are Professors at the Department of Geology
and Petroleum Geology, School of Geosciences, University
of Aberdeen. Andrew Hurst specialises in Petroleum
geology while Nigel Trewin specialises in early terrestrial
environments, palaeoecology and sedimentology. Their
knowledge and expertise is evident in the amount of detail
contained within this excursion guide. Some knowledge
of geology is expected from the reader, but I recommend
this excursion guide to anyone who wishes to study the
geology of North East Scotland and as a library book for
students who are following the Evolution of Britain module
at A2.
Ray Humphreys
The excursions are focussed on:–
• The Devonian Old Red Sandstone of Caithness
and covers the major features of the Caithness
Flagstone from the marginal unconformities,
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 65

Vesuvius – A Biography
Alwyn Scarth
Terra Publishing 2009,
ISBN 978-1-903544-25-9 £24.95
needed spatial dimension as the various stories unfold.
Most of these are written with the immediacy of an eye
witness account and Scarth has graphically detailed the
eruptions, sometimes on an hourly basis. The chapters are
well referenced with further reading at the end and an
extensive bibliography. I particularly like the many aside
notes, blocked in a different background colour, which
further develop a geological point, some social comment,
or simply an interesting piece of historical perspective.
So we read that “Soon after 10.00 a.m. on 17th December
(1631), it seemed indeed that the Last Judgement was
about to be delivered.... An old women in Granatello
described how the flow had emerged completely white,
‘like a silver baton’ and had rolled over the ground at first
(as a pyroclastic flow).” Written in this way the science
is secondary but implicit in the narrative for those with a
geological background. And it makes a great read.
Vesuvius is a dangerous volcano, though quite how
dangerous I was not really aware of until reading this book.
Most students in exams will recall specifics of the AD 79
eruption that destroyed Pompeii and Herculaneum (some
even using the correct spelling) and, true to form, this
book details this eruption, but only as one of the many
events that has transformed Naples and the surrounding
Province of Campania. For Alwyn Scarth, well known to
us for his many books on the subject of volcanoes, has
written a biography of Vesuvius from its birth long before
mankind first settled in the region, right up to the present,
with some worrying speculation about the inevitable future
events.
The book was written in 2009 and is currently only
published in hardback by Terra Publishing – well known
to us to be specialists in producing readable books in the
Earth sciences. This book is no exception and consists of 13
chapters chronicling the daily history of each major event,
not only of Vesuvius, but also the Campi Flegrei caldera to
the west. This is based on the latest geological research,
backed up by contemporary historical accounts. Each
chapter is well illustrated with black and white satellite
images, photos, maps, diagrams and art that give a much
Campania has one of the longest recorded human histories
anywhere in the world, and volcanoes have played a
dominant role in fashioning the human environment. This
is, therefore, not just a biography of a volcano but, also
bound up in the pyroclastic deposits, mudflows and lava,
is a biography of the changing social, spiritual, intellectual
and political development of Campania as it finds its place
in the changing world. So in addition to the letters of Pliny
the Younger and the aid relief organised by the Roman
Emperor Titus following the AD79 eruption, we read about
the archaeological work of Giuseppe Fiorelli in excavating
the remains at Pompeii, and learn of the work of Sir
William Hamilton (of Emma Hamilton and Admiral Nelson
fame) in the 1760’s as one of the founders of modern
volcanology. And there are many more.
In all, this is a very readable book for the non specialist as
well as those with a little more geological knowledge and
a great book to take with you should you be intending
to take the equivalent of the eighteenth century “Grand
Tour”. There are also some great case studies for students
taking the Geology of the Human Environment course at
AS. You are promised explosive stuff and this book delivers.
And with this view of the volcanic history of the region, the
overriding impression is that, inevitably, this is something of
which we have not heard the last!
Peter Loader
St. Bede’s College, Manchester
66 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

Diary
March 2010
1st March until 11th April
Veolia Environnement Wildlife Photographer of the Year
exhibition
Natural History Museum
Cromwell Road
London
SW7 5BD
1st March until 27th May
Ida fossil cast on display
Natural History Museum
Cromwell Road
London
SW7 5BD
10th March
Lecture: Carbon Capture and Storage: Our Only Hope to
Avoid Global Warming?
The Geological Society,
Burlington House.
Piccadilly, London,
W1J 0BG
Contact: www.geolsoc.org.uk/
24th – 25th March
Conference: Carbon Storage Opportunities in
The North Sea
The Geological Society,
Burlington House.
Piccadilly, London,
W1J 0BG
Contact: www.geolsoc.org.uk/
27th – 28th March
Rock’n’Gem Show
Cheltenham Racecourse
Prestbury Park,
Cheltenham,
Gloucester
Contact: www.rockngem.co.uk
April 2010
9th – 10th April
Geographical Association Conference: Geography: The Big
Picture
Derby University
Contact: www.geography.org.uk
14th April
Lecture: The Search for Source Rocks on Mars
The Geological Society,
Burlington House.
Piccadilly, London,
W1J 0BG
Contact: www.geolsoc.org.uk/
24th – 25th April
Rock’n’Gem Show
Newark Showground,
Winthorpe,
Newark, Notts
Contact: www.rockngem.co.uk
May 2010
12th May
Lecture: The Evolution of a Megaproject on Sakhalin Island
The Geological Society,
Burlington House.
Piccadilly, London,
W1J 0BG
Contact: www.geolsoc.org.uk/
June 2010
5th – 6th June
Rock’n’Gem Show
Kempton Park Racecourse
Staines Road East (A308),
Sunbury on Thames, West London
Contact: www.rockngem.co.uk
www.esta-uk.net Vol 35 No 1 2010 Teaching Earth Sciences 67

9th June
Lecture: The Chemistry of the Oceans: Past, Present &
Future
The Geological Society,
Burlington House.
Piccadilly, London,
W1J 0BG
Contact: www.geolsoc.org.uk/
26th – 27th June
Rock’n’Gem Show
Elsecar Heritage Centre
Elsecar,
South Yorkshire.
Contact: www.rockngem.co.uk
30th June
Conference – Lyell Meeting 2010: Comparing the
geological and fossil records: implications for biodiversity
studies
Flett Lecture Theatre,
Natural History Museum,
Cromwell Road
London
SW7 5BD
Contact: www.nhm.ac.uk
July 2010
3rd – 4th July
Rock’n’Gem Show
Newcastle Racecourse
High Gosforth Park,
Newcastle-upon-Tyne
Contact: www.rockngem.co.uk
August 2010
7th – 8th August
Rock’n’Gem Show
Kempton Park Racecourse
Staines Road East (A308)
Sunbury on Thames,
West London.
Contact: www.rockngem.co.uk
14th – 15th August
Rock’n’Gem Show
Royal Welsh Showground
Builth Wells,
Mid Wales.
Contact: www.rockngem.co.uk
September 2010
8th September
Lecture: A Lot of Hot Air: Degassing and Volcanic Eruptions
The Geological Society,
Burlington House.
Piccadilly, London,
W1J 0BG
Contact: www.geolsoc.org.uk/
17th – 19th September
ESTA Annual Course & Conference
Leicester University
Contact: linmarshall@btinternet.com
68 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net

9th June
Lecture: The Chemistry of the Oceans: Past, Present &
Future
The Geological Society,
Burlington House.
Piccadilly, London,
W1J 0BG
Contact: www.geolsoc.org.uk/
26th – 27th June
Rock’n’Gem Show
Elsecar Heritage Centre
Elsecar,
South Yorkshire.
Contact: www.rockngem.co.uk
30th June
Conference – Lyell Meeting 2010: Comparing the
geological and fossil records: implications for biodiversity
studies
Flett Lecture Theatre,
Natural History Museum,
Cromwell Road
London
SW7 5BD
Contact: www.nhm.ac.uk
July 2010
3rd – 4th July
Rock’n’Gem Show
Newcastle Racecourse
High Gosforth Park,
Newcastle-upon-Tyne
Contact: www.rockngem.co.uk
August 2010
7th – 8th August
Rock’n’Gem Show
Kempton Park Racecourse
Staines Road East (A308)
Sunbury on Thames,
West London.
Contact: www.rockngem.co.uk
14th – 15th August
Rock’n’Gem Show
Royal Welsh Showground
Builth Wells,
Mid Wales.
Contact: www.rockngem.co.uk
September 2010
8th September
Lecture: A Lot of Hot Air: Degassing and Volcanic Eruptions
The Geological Society,
Burlington House.
Piccadilly, London,
W1J 0BG
Contact: www.geolsoc.org.uk/
17th – 19th September
ESTA Annual Course & Conference
Leicester University
Contact: linmarshall@btinternet.com
68 Teaching Earth Sciences Vol 35 No 1 2010 www.esta-uk.net