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FOUNDED IN 1977 

Picture courtesy of Coaltech 

AUGUST 2008 Vol. 1 

Editor: Stoffel Fourie 

sfourie@csir.co.za 

August 2008 No.1


SAGA 

NEWSLETTER 

August 2008 

In this issue... 

* President's report for 2008-2009 * Geophysical Dictionary 

* Get to know our new SAGA President. * New Equipment for the Physical Property 

Laboratory at the CGS. 

* Past president’s Report 2007-2008 * Hired, fired, and retired. 

* Note from the editor * The DGS of Botswana 

* Special honour for Manfred hauger * A true physics story. 

* SAGA’s Armageddon * Shallow high resolution seismic surveys: 

Resolution and frequency content is everything – 

A simple tool to help with survey planning: C.J.S. 

Fourie and C.L. van Dam. 

2008-2009 Council Members 

President Mr. S.J. du Plessis CSIR sduplessis1@csir.co.za 

Vice-President Mr. A. Wolmarans De Beers Anton.wolmarans@debeersgroup.com 

Past-President Ms. P. Du Pisani Anglo American pdupisani@angloamerican.co.za 

Treasurer Mr. G. Campbell Gap Geophysics gapgeo@icon.co.za 

Editor Dr. S. Fourie CSIR sfourie@csir.co.za 

Members Mr.T. Odgers Red Dog S.S. reddog@geoafrica.co.za 

Mr. A.R. Vorster De Beers anre.vorster@debeersgroup.com 

Ms. S. J. Webb Wits. Geophysics webbs@geosciences.wits.ac.za 

Mr. K. Trofimczyk Anglo American ktrofimczyk@angloamerican.co.za 

Dr. D. Vogt CSIR dvogt@csir.co.za 

Dr. Lindsay Linzer 

Lindsay.Linzer@gmail.com 

Western Cape Branch Committee 

Chairman Mr. W. de Meyer 

Vice chairman Solomon Lephoto PetroSA solomon.lephoto@petrosa.co.za 

Sec/ Treas Vincent Mashaba PetroSA Vincent.mashaba@petrosa.co.za 

Members Tobias Tonsing Tullowoil Tobias.tonsing@tullowoil.com 

George Smith UCT George.Smith@uct.ac.za 

Buhle Hlatshwayo Tullowoil Buhle.hlatshwayo@tullowoil.com 

Heinz Pferdekamper Tullowoil heinz.pferdekamper@tullowoil.com 

Geoffrey Jackson Tullowoil Geoffrey.jackson@tullowoil.com 

Lihle Madyibi UCT Lihle.madyibi@uct.ac.za 

SAGA ADMIN 

Jann Otto 

RCA Conference Organisers 

P O Box 72147 Parkview 2122 

011 728 8173 fax 011 728 1675 

events@rca.co.za www.rca.co.za 





FEES 

Anyone wishing to join SAGA can please contact Jann Otto (ADMIN) for 

assistance: 

Members R250.00 

Associate/affiliate members R250.00 

Student members R60.00 

Sustaining/institutional members R2500.00/US$775.00 

Overseas members 

US$37.50 

SADC Countries R250.00 

ADVERTISEMENTS 

Anyone wishing to advertise in the SAGA newsletter must please contact the 

Editor (Stoffel Fourie at sfourie@csir.co.za). Rates (per issue) are as shown below; 

½ page ad. b/w R100/$50 Full page b/w R200/$100 

Full colour full page (min. 2 issues) R625/$625 

Brochure insert (


SAGA President 2008-9: Report 

Your newly elected SAGA President is Stefaans du Plessis, Research Group Leader 

at the CSIR Applied Geoscience research group. 

Stefaans in Peru, Consulting to a mining company (December 2007) 

The SAGA AGM held in May 2008 was a very enjoyable affair at a function held at 

the old Johannian club in Houghton, Johannesburg. It was a very cosy venue with 

fires to neutralise the effect of the cold winter evening. The evening was attended by 

around 40 people. Petro du Pisani, the SAGA President for 2007-8 presented her 

report on the activities during her term. Her report is elsewhere in this newsletter. The 

SAGA year 2007-8 under Petro’s competent leadership and enthusiasm was a busy 

year for SAGA, with two visiting SEG distinguished lecturers, monthly talks, three 

courses (Uranium, MT and Geophysics in Exploration), as well as the highly 

successful SAGA2009 Biennial Conference at the Wild Coast Sun. On behalf of me, 

as new SAGA President and the SAGA committee, and SAGA members, we would 

like to sincerely thank you for your efforts in making 2007- 8 a most successful year 

for SAGA. Well done and congratulations on a significant achievement. It certainly 

was a lot of fun as well! 

The SAGA treasurer, Geoff Campbell arrived just in time for delivering his usual 

eloquent, clear and concise and entertaining report. SAGA is happy to report that the 

finances look solid at the moment. 

In order to strengthen our relationship with the Geological Society of South Africa 

(GSSA), we invited a number of GSSA representatives to the SAGA AGM. From the 

Egoli Branch of the GSSA, we had Dr George Henry (Chairman Egoli Branch of the 

GSSA) and Erika Barton (who sends out the SAGA talk announcements to Egoli 

Branch members) as well as a Vice President of the GSSA, Dr Pamela Naidoo, 

representing the GSSA, attending the SAGA AGM. During 2007, we had an informal 

arrangement whereby Egoli Branch GSSA talks announcements were sent to SAGA 

members and SAGA talks announcements in return to Egoli Branch GSSA members. 





The highlight of the evening was an excellent talk by Dr Ludwig Combrinck from the 

Hartebeeshoek Radio Astronomy Observatory (HARTRAO) facility on current and 

future exploration of the moon. Terry Odgers was very surprised to hear that the 

moon is drifting away from the earth at about 4 cm per year – admittedly, I also did 

not know that… Apparently there’s also a lot of Helium on the surface of the moon – 

waiting to be exploited! 

During 2007, RCA, Robbie Cameron’s events company and Jann Otto took over the 

SAGA Secretary role, building on the highly successful and mutually beneficial 

relationship SAGA has developed with RCA, whilst organising the SAGA conference. 

We have made great progress towards organising SAGA2009, and look forward to 

working together during the term 2008-9. Thank you to Robbie and Jann and the 

other RCA staff members for their enthusiasm and most professional service. 

A special thank you is required for Stoffel Fourie who has volunteered to do the 

SAGA newsletter. Stoffel got stuck in immediately and this is his first effort - I hope 

you enjoy reading the newsletter. Thank you Stoffel, for your enthusiasm and rapid 

delivery of the newsletter after taking over the task. 

Since the AGM we had the following monthly talks: 

July 2008: Dr. Stoffel Fourie talked on his PhD topic “In-Situ Subsurface Density 

Estimations Using a Seismic Technique” 

August 2008: Professor Gordon Cooper talked about potential field filters 

Activities planned: 

September 2008: Talk by Stefaans du Plessis, “Recent Dighem dyke detection 

survey results from a Total Coal colliery”. 

October 2008: Wireline logging course presented by Marcus Chatfield 

November 2008: Hoping to host an SEG distinguished lecturer 

Please approach the committee if you have done something interesting that you 

would like to present at a SAGA monthly meeting, or if you know someone who has 

something to present. 

SAGA 2009 Biennial conference in Swaziland “From ancient rocks to modern 

techniques”. 

The main event in 2009 to look forward to is the SAGA2009 biennial conference to 

be hosted 13-18 September 2009 in Swaziland. Swaziland is home to the oldest 

dated rocks in Africa “The ancient gneiss complex”. The nearby Barberton Mountain 

land is one of the best exposed greenstone belts in the world. Swaziland is also close 

to the famous and large Kruger Park game reserve, borders Mozambique that is an 

excellent diving and fishing and beach holiday destination. Swaziland bosts a couple 

of game reserves, all within 40 minutes drive of the Royal Swazi Spa hotel, located 

outside Mbabane (the capital of Swaziland). Swaziland and the Milwane game 





reserve (10 minutes drive from the Royal Swazi Spa) is a top birding destination, and 

early morning birding trips will be organised. At Hlane game reserve (about a 40 

minute drive from the Royal Swazi Sun), you can walk with rhinos. 

We are very happy to report that the sponsors and exhibitors have already started to 

stake their claims and have committed themselves to supporting SAGA2009. Thank 

you to Keith Fisk (Getech), CGG Veritas (Michele Denis), Robert Wilson and Laurent 

Ameglio (Terraquest), for sponsoring big events at 2009 such as the The Gala Dinner 

with a Difference ‘House on fire’, the Shebeen evening (SAGA2007 it was the ‘pirate 

party’), and the opening of the trade show ice breaker cocktail event. Simon Bate 

(Aegis) is sponsoring the Golf day, Ria Tinnion (Geosoft) the ‘pub in the hub’. We 

highly appreciate your support. Every day more sponsors are coming to the party. 

Other sponsorship options are available as well www.sagaonline.co.za 

It is also fantastic that Maarten de Wit is again bringing Inkaba yeAfrica to SAGA, 

and Inkaba yeAfrica will run parallel technical sessions at SAGA. 

We are also indebted to Professor Alan Jones (DIAS), bringing SAMTEX to 

SAGA2009. 

Africa Array will again be a major participant at SAGA2009 and for that we thank 

Professor Dirks, Ray Durrheim, Sue Webb and all the Africa Array students. 

We look forward to welcoming you all at SAGA2009. 

We also plan lots of field trips: Komati valley, home of the Komati-ites, spinnifex 

textures etc; Sheba (mine) Top quad bike trip; Possibly Sheba mine (underground 





visit) and Lily mine as well as possibly visits to mining activities in Swaziland in 

conjunction with the Egoli Branch of the GSSA. 

In addtition to this, a number of workshops and courses will be on offer. We also 

hope to have more than one SEG distinguished lecturer at the SAGA2009 

conference. 

The SAGA2009 conference committee: 

Conference Chair: Stefaans du Plessis 

Technical Chair: Dr. Declan Vogt 

Workshops and Courses and social events: Petro du Pisani 

Gholf and field trips: Kazek Trofimczyk 

Website: Terry Odgers 

Special sessions: Ray van Rensburg 

Student affairs and SEG: Sue Webb 

Professional Events Company: RCA, Jann Otto, Robbie Cameron and team 

Sponsored by GETECH 









Get to know our new SAGA President: - Stefaans du Plessis 

Stefaans completed his B.Sc. degree in geology and physics at the University of 

Potchefstroom (now Northwest University) in 1988, and went on to study for B.Sc. 

Honours in Exploration Geophysics at the University of Pretoria in 1989. He joined 

Anglovaal (later Avmin) in 1990 and worked on both mine and exploration projects in 

southern Africa. He was part of the exploration team that discovered the massive 

sulphide deposit that became the Nkomati nickel mine, and also pioneered the use of 

the airborne Dighem technique used to detect non-magnetic dykes in coal fields, and 

in collaboration with John Bishop, successfully used down hole magnetometric 

resistivity (DHMMR) at Nkomati to detect massive sulphides – the first time the 

technique was used on excellent conductors – DHMMR was developed to detect 

weak conductors. He interpreted 30,000 line km of SYSMIN programme Airborne EM 

data over the eastern extension (under surface cover) Matchless Amfibolite belt, as 

well as interpreting the ground EM surveys on identified targets from this airborne EM 

survey. Stefaans then transferred to Avgold as Chief Geophysicist from 1998 to 

1999, working on projects in both East and West Africa. He did private consulting and 

lecturing for a brief spell in 2000-2001, and then joined Anglo American as a 

Divisional Geophysicist, responsible for consultations, oversight and assurance, and 

group support for the company's subsidiaries. He was involved in the interpretation of 

the high resolution Midas aeromagnetic surveys flown over all of Anglo Platinum 

mines on the Bushveld Complex. Stefaans also spent time in Morocco interpreting 

EM surveys, and was responsible for a successful Coaltech 2020 aeromagnetic 

project whereby all the industry airborne magnetic data was sourced and collated into 





a map. A dyke lineament map for the Witbank and Highveld coalfields was also 

produced. 

In February 2006 Stefaans left industry to become the Research Group Leader 

(RGL) in the Applied Geoscience (AG) Research Group of the Mining Competence 

Area - Natural Resources and the Environment of the Council for Scientific and 

Industrial Research (CSIR). He gained managerial experience by overseeing the AG 

research projects involving both geophysical and geological inputs, as well as 

conducting several consulting projects. He initiated and managed the flagship "Glass 

Rock" Parliamentary Grant Project, now into its third year. He also oversaw the 

commercial borehole radar surveys that are now a widely used technique. He has 

also been acting Mining Competence Area Manager when the need arose. 

Stefaans joined African Nickel, a junior exploration company, as Consulting 

Geophysicist in September 2008, thereby starting another chapter in the adventure 

called life. 

Stefaans has been an active member of SAGA since around 1990, presenting at 

many of the conferences, and was chairman of the committee that put together the 

very successful and enjoyable conference "Making Waves" at the Wild Coast Sun in 

October 2007. During 2007 he was Vice President of SAGA. He has also volunteered 

to chair the team organising the next SAGA conference in 2009 to be held in 

Swaziland. This conference is going to be even better than the Wild Coast 

conference and it is a must to attend! 

SAGA Past President’s report 2007/8, Petro du Pisani, Anglo American 

Dear SAGA members 

The 2007/8 SAGA year has flown past. It has been a full and eventful year, 

which has confirmed that SAGA is an active and enthusiastic association within 

the Southern African geoscientific community. 

The highlight of the year was the 2007 SAGA Biennial Technical Meeting and 

exhibition which took place at the Wild Coast Sun in October 2007. 





2007 Conference 

The theme of the conference was “Making Waves” which referred as much to 

geophysical waves as to the contribution that our members make through out 

Industry, Research and Academia. The conference committee was led by 

Stefaans du Plessis, who did an excellent job of coordinating the effort and 

keeping everybody calm. Conference organizers RCA were contracted to organize 

the conference and their friendly and efficient manner ensured that the 

conference ran smoothly with no major hiccups. 

Prior to the conference various courses and workshops were presented over two 

days, such as Inkaba ye Africa, SAMTEX, In-mine Geophysics workshop, Geosoft 

and Intrepid courses. A field trip from Durban to the Wild Coast Sun was led by 

Dr. Geoff Grantham. 

The conference was attended by a record number of delegates and exhibitors 

setting the bar high for the next conference to be held in Swaziland in 2009. 

Without various sponsors (listed on our website) the conference would not have 

been possible and they are sincerely thanked for their contributions. The 

standard of technical presentation and content was raised in 2007 by a peer 

review process of papers, coordinated by Lindsay Linzer, the Technical Chair for 

the conference. The Best paper awards went to: 

Fugro Best Paper: Frikkie de Beer (Necsa) 

Fugro 2 nd paper: Declan Vogt (CSIR) 

Fugro 3 rd paper: Susan Webb (Wits) 

Fugro 4 th paper: Andreas Chwala (IPHT-Jena) 

Best Student paper: Stephanie Scheiber (Wits) 

Best Mining paper: Anton Wolmarans (De Beers) 

Best poster: Fatheela Kaldine (Anglo American) 

Best student poster: Marion Miensopust (DIAS) 

The full conference proceedings have been given an ISBN number and are 

available at the National Library. 

As usual the comprehensive technical programme was complimented by a busy 

social programme which included a golf day, Icebreaker, Beach party and Gala 

dinner. Two awards were presented at the French-themed gala dinner, namely: 

The geophysical enterprise award to Ray van Rensburg, and 

The meritorious geophysical service award to Reynie Meyer. 

The conference was huge success technically, socially and financially. Planning 

for an even bigger and better conference in 2009 is already underway. Members 

are encouraged to start conceptualizing their brilliantly scientific and thought 

provoking papers for submission early in 2009. 

Administration 

In 2007, after doing an excellent job of organizing SAGA’s administrative affairs 

for 2 years, Gorete de Oliveira handed over the reigns to Jann Otto from RCA. 

RCA have been running the administrative function for SAGA, attending 





meetings, taking minutes and making sure members pay their dues. The Council 

thanks both Gorete and RCA for their contribution in 2007/8. 

Monthly meetings and talks 

A number of successful talks were hosted in the 2007/8 year. Talks were given 

by: 

Vic Simmonds (Crimesight) 

Allan Place (MDA Geospatial Services) 

Kazek Trofimczyk (Anglo American) 

Ken Witherley (Condor Consulting) 

Wayne Pettit (BHP Billiton) 

SAGA was also privileged to host a SEG distinguished lecturer in May 2008. Tad 

Ulrych entertained a packed CSIR auditorium with his talk: 

“The role of amplitude and phase processing and inversion.” 

Courses and workshops 

SAGA ran two highly successful courses in the previous term, namely: 

Magnetotellurics for Natural Resources by Dr. Alan Jones in March 2008, and 

Geophysics in Exploration (in conjunction with GSSA) in April 2008. 

AGM 

The new SAGA council was elected at the AGM held on 6 June 2008 at the 

Johannian club in Johannesburg. 

Stefaans du Plessis (President) 

Anton Wolmarans (Vice-President) 

Geoff Campbell (Treasurer) 

Stoffel Fourie (Newsletter Editor) 

Terry Odgers 

Declan Vogt 

Anre Vorster 

Kazek Trofimczyk 

Lindsay Linzer 

Petro du Pisani (Past president) 

Sue Webb (Student affairs & SEG liaison) 

New members elected to the council included Anton Wolmarans and Stoffel 

Fourie (who will be the new Newsletter Editor). Standing down from the Council 

were Magdel Combrinck and Dave Hatch. Thanks to Magdel and Dave for their 

outstanding contribution during the many years they both served on the Council. 

Manfred Hauger was awarded a SAGA meritorious award at the AGM for is long 

term to contribution to South African geophysics. 

President’s comment 

2007/8 has been an excellent year of collaboration, with SAGA making their 

voices heard at the First SEG General Assembly of all associated Geophysics 

Societies In January 2008. This resulted in a distinguished lecturer gracing our 

shores and will hopefully lead to many learning experiences in the future. 





Furthermore SAGA collaborated with the Geological Society to present a highly 

successful introductory Geophysics course. Efforts have been made in 2007/8 to 

include and communicate with our Western Cape branch members and I hope 

that these ties can be strengthened through continued dialogue and cooperation. 

The geoscientific community faces many exciting opportunities and challenges 

over the next year, including booming commodity prices combined with the 

challenge of rising skills shortages. SAGA will continue to serve is members to 

best its best abilities in these interesting times. 

None of the achievements SAGA can celebrate for the 2007/8 term would have 

been possible without the fantastic support provided by the SAGA Council, RCA 

and to you the SAGA members. Thank you all! 

Best regards 

Petro du Pisani 

SAGA President 2007/8 

Note from the Editor…… 

It is a while since the last SAGA Newsletter was released. We hope that with this 

edition of the SAGA Newsletter we will spark a new interest within the SAGA 

members to contribute actively towards the newsletter. Please also contribute 

towards the dictionary. As usual, we will give news about the hired, fired and 

married…. of our community, but we would also like to get contributions from our 

neighbours and abroad; for an added international flavour. 

In this edition we will remind you of our next SAGA Conference in 2009 and we 

honour some of our geophysicists that made a large contribution to our community 

during the last 50 years. We would also like publish papers of our members and 

students. If we get enough support we would like to compile a volume of papers at 

the end of the year of the papers published in the SAGA newsletter. 

In the next issue…….We will report on more of our distinguished members that 

contributed to our community. We will continue with the dictionary and publish a 

paper by Ian Saunders on the national seismology network. 

SAGA also plans to bid for the International EM Conference to be held in South 

Africa in 2012. The bid committee is currently Geoff Cambell of GAP Geophysics, 

Valeriya Zadorozhnaya of the CGS and Stoffel Fourie of the CSIR. Help was 

pledged from Alan Jones, Edgar Stettler and Mark Hamilton. 

Enjoy it…. Stoffel 





A Special Honour: - Meritorious Service Award to: Manfred Hauger – 

SAGA recognise his long term contributions of 50 years to the South African 

geophysical community. 

Manfred Hauger was born on 25 

September 1930 at Grootfontein in South 

West Africa. He started primary school in 

1937 at Otavi. He started secondary 

school in 1944 in Windhoek. He attended 

the HPS German school. He started a 

B.Sc with Geology at the University of 

Pretoria in 1952, with Simon Zacht and 

Prof. Lombaard. He could not finish his 

studies due to finances. The funding he 

should have received from family in East 

Germany could not reach him due to the 

Berlin Wall. 

Manfred started to work in February 1953 

as a technician at the Geological Survey 

of South Africa. He started field work in 

April 1953 near Hammanskraal. They 

stayed in a field camp with tents. They 

did the siting of boreholes for 

groundwater near Hammanskraal, using 

the Gane-Enslin Resistivity equipment. 

The PARI instrument (Phase Amplitude 

Ratio Instrument) was also used. It was a 

Tube driven Electromagnetic system. It 

used a round Tx loop with a 1.5kw 220V 

generator. This system was very 

sensitive to vertical structures and thus 

good for groundwater. Manfred had and 

still has an extensive knowledge of tubes, 

and was able to fix the PARI system. 

He also did groundwater exploration for 

the Department of Agriculture on the 

Springbok Plane. The purpose was to 

find boreholes that can deliver more than 

10 000 Gallons per hour to irrigate 

tobacco fields. They suspected this will 

destroy the aquifer, which happened 9 

years later. 

He developed the first water level 

instrument in South Africa to replace the 

old wet measuring tape system. It used 

a voltmeter and was more accurate. 

Multiple copies of this system were built 

by the Geological Survey. 

In 1954 he did the first geophysical 

surveys that started the Rooiberg Tin 

mine. He could map the faults and 

dykes. A survey near Messina was done 

to detect the shallow dipping Copper 

beds in the area. 

He did a self potential survey near 

Barberton in 1955. This started the 

beginning of Barbrook Goldmine. To be 

more mobile Manfred got himself a 

caravan. He did water divining for all the 

railway stations between Warrenton and 

Kimberley. Water was needed for the 

small communities that serviced the 

stations, but more so for the steam 

engines. 

In 1955, Bellsbank, close to Barkley West 

opened for diamond prospectors and 

diggers. He was commissioned to detect 

the Kimberlite Dykes and Fishers. The 

large contrast in resistivity between the 

Kimberlites and the Dolomites produced 

very good results. The thickness varied 

between 10cm to 10m. It is a very dry 

and arid place with dry boreholes. 





When deeper digging started there was 

so much water that it could not be 

pumped to continue mining. Mining had 

to stop at the water table. 

During the mining process a digger found 

a piece of meteorite. Manfred organised 

via the Commissioner of Mines that it 

was placed in a Museum. 

In 1956 the Goldmine Industry started to 

experience more problems with 

groundwater. Manfred started a 

weekly/monthly borehole measurement 

program where the water levels were 

measured in deep exploration holes. 

Borehole elevations were measured with 

Barometers. These results showed that 

the area can be divided into separate 

compartments. 

In 1957 Manfed and Dr. Kleywegt started 

to explore for the Dolerite and Syenite 

dykes in the Wits. All dyke positions were 

measured with a “vlaktafel” and Alidade 

and a map was made. This started the 

pumping of the Wits to save the Gold 

Mining industry. As the water table 

dropped due to pumping, fountains dried 

up like Gemsbokfontein, Venterspos, 

Bank and Oberholzer. Sinkholes started 

to appear. 

By 1961 it was not clear what would be 

the best way to detect the areas of 

possible sinkhole formation. A test 

gravity survey was started and the results 

indicated that a gravity survey was the 

best way to detect possible weak zones. 

He did some heat flow experiments by 

measuring temperatures in shallow 

boreholes, 24 hours after they were 

drilled. They were in a profile across the 

Venterspos Dyke. The dyke gave a very 

good magnetic and electromagnetic 

response. The temperature readings 

corresponded very well with the 

geophysical results, confirming that more 

heat flow form igneous structures. 

The South African Railways asked for a 

survey in De Aar to find water for their 

large steam train fleet. They used water 

from the Brakriver at Karoluspoort. He 

used resistivity and a seismograph that 

was developed by the CSIR to detect the 

size and depth of the aquifer. It was the 

first time that a hammer seismic 

instrument was used on such a survey. 

The results were proved by Auger holes. 

Pump tests were done. A tracer 

Flourosine was used for the first time to 

try and detect the groundwater flow, 

which didn’t give good results. It was 

later established that the organic material 

and the plant roots absorbed all the 

tracer molecules. Draining tests were 

done to pump water into dams. Only 

dams with plants at the bottom drained, 

the rest was only normal evaporation. 

In 1962 his involvement with the seismic 

method started. Manfred did the survey 

for a pipeline between Kouga Dam and 

Port Elisabeth and a seismic refraction 

survey for a bridge near Despatch. He 

became more involved with the seismic 

team, especially when instruments broke 

– Radio tubes. Manfred finished off the 

survey between Glencorner, Gamtoos 

and Hanky. 

Manfred started the seismic survey near 

Dannhauser and Dundee for Coal 

reserves. The camp was later moved to 

Laingsburg. He did seismics from 

Laingsburg to Barrydale and from 

Laingsburg to Sutherland. Later, a profile 

was done from Koringplaas to 

Sutherland. 

In 1963 he took part in seismic profiles 

between Jamestown and Stutterheim and 

near Middelburg. 

In 1964 he converted a seismic refraction 

system to be more portable. He did 

surveys with this instrument at Milnerton 

and Cape Town. 





He also did the surveys for the 

Theewaterskloof Dam in Riviersonderend 

and the tunnel through the Fransch Hoek 

mountains into the Berg River. 

He did surveys between 1966 and 1970, 

across the PE Cretaceous basin, starting 

at Kinkelbos. He did a seismic profile at 

Colchester where the CSIR did some 

deep resistivity work, to compare results. 

A borehole position was established, and 

it was the only borehole in the PE 

Cretaceous Basin that produced a little 

bit of oil. The next surveys on the basin 

were then done at Oudtshoorn. 

By 1971 Manfred did a seismic refraction 

survey at Melkbos Strand for the 

Koeberg Nuclear power station. The 

government also drilled about 500 

boreholes near Beaufort West for 

Uranium exploration. Manfred did the 

radiometric logging of the holes. 

Manfred did the geophysical surveys for 

the Sterkfontein Dam and the Kilburn 

Pumpstation. Manfred did the Seismic 

Refraction Survey for the pipe line form 

the Grootvlei Dam near Standerton to 

Secunda, also in 1971. 

Between 1972 and 1975, Manfred took 

over the Paleomagnetic Laboratory from 

Dr. Henthorn. He had to do instrument 

support. He immediately improved the 

design of the Helmholtz cage that is to be 

used during AF-Demagnetisation. 

Manfred designed and build the neutron 

gamma system for a borehole probe. He 

measured all the boreholes drilled for 

coal in the Secunda area with this probe. 

From 1976 to 1980, Manfred build a 

prototype DC equipment (ERMA) to find 

clay deposits in the west rand. The same 

receiver can also record EM signals. 

In 1985, together with Dr. Edgar Stettler, 

he started with the development of MT 

equipment. He did MT-profiles from 

Sishen to keimoes and from Darling to 

Moreesburg and also stations in Kokstad 

and Chinoyi in Zimbabwe. 

He developed software for the 

Paleomagnetic Laboratory to control the 

data acquisitioning and processing. 

In 1989 Manfred was involved with the 

testing of the new Pulse EKKO GPR 

system, with Cristo Craill and Stoffel 

Fourie. 

He started with work on the site for the 

Mohale Dam and at the hot water springs 

near Tsipise. 

He did the geophysical investigation at 

Vaalputs for the nuclear waste site, and 

developed a drilling system with a small 

diamond drill to take paleomagnetic 

samples. 

Several MT-Surveys followed, and he 

retired from the Geological Survey in 

1994. 

He was contracted to stay on at the 

Council for Geoscience. He started then 

on the development of the Microlight 

Airborne system, together with John 

Kulper. 

He also started with the development of 

the RIPS system. In 2005 his contract 

with the CGS was not renewed. Manfred 

still do development work for 

improvements on the RIPS system and 

to debug new palaeomagnetic 

equipment. He is also developing an 

EKS system at the moment. He is still a 

member SAAG and the PSA. 





SAGA’s Armageddon (July 2008): - Look what you have 

missed. 

Near-Earth Asteroids 

Potentially Hazardous Asteroids (PHAs) are space rocks larger than approximately 

100m that can come closer to Earth than 0.05 AU. None of the known PHAs is on a 

collision course with our planet, although astronomers are finding new ones all the 

time. 

On July 24, 2008, there were 962 potentially hazardous asteroids. 

July 2008 Earth-asteroid encounters: 

Asteroid Date(UT) Miss Distance Magnitude. Size 

2003 YE45 July 13 16.5 LD 15 1.4 km 

2008 BT18 July 14 5.9 LD 13 1.0 km 

2003 LC5 July 15 62 LD 16 1.4 km 

2008 NP3 July 17 6.8 LD 18 85 m 

Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 

LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest 

approach. 

Reference: www.spaceweather.com 

SAGA’s Geophysical Dictionary 

A 

Acceleration 

The rate at which an object's velocity changes with time. 

Accelerometer 

An instrument that measures acceleration. 

Airborne Gravity 

Airborne gravity is the measurement of the gravity field from the air, using an 

aeroplane, airship or satellite. 

Altitude Correction 

An altitude correction is made to correct or compensate for the height or elevation 

above a certain reference level. In the earth sciences it is usually above sea level. 

Altitude corrections are usually made in barometric, gravity, magnetic, seismic, radio 

nuclide and satellite applications. 

Please contribute. Ed. 





REPLACEMENT EQUIPMENT 

FOR THE PHYSICAL 

PROPERTIES LABORATORY 

The function of the Physical Properties 

Laboratory of the Council for Geoscience is 

to facilitate research on the rock magnetic, 

palaeomagnetic and physical properties of 

rock samples. 

During 2007 the Physical Properties 

Laboratory has acquired several new 

instruments for the study of rock magnetic 

and palaeomagnetic properties. These 

instruments include: 

• The JR-6A dual speed spinner 

magnetometer from AGICO for 

measurement of remnant magnetization of 

rocks using classical (i.e. non-quantum, 

non-cryogenic) operating principles. 

Kappa Bridge 

• The CS-3 furnace apparatus which is 

attached to the MFK1-FA model and 

measures the high temperature variations 

of magnetic susceptibility which enables the 

determination of Curie transition 

temperatures. The Curie temperature can 

be used as a diagnostic tool to identify 

magnetic mineralogy. This is a tool has until 

now not been available at the Council for 

Geoscience. 

• The MMTD80 thermal demagnetizer from 

Magnetic Measurements Ltd (UK) which 

has the capacity to demagnetize 80 

samples simultaneously. The necessary 

attachments for the MMTD80 to enable 

Thellier-Thellier experiments have also 

been acquired. 

Spinner Magnetometer 

• The MFK1-FA multi-function kappa bridge 

from AGICO for the measuring anisotropy 

of magnetic susceptibility (AMS) of rocks 

as well as in-phase and out-of –phase bulk 

magnetic susceptibility in weak variable 

fields and at 3 different operating 

frequencies. This instrument can even 

measure the anisotropies of diamagnetic 

and near-zero susceptibility samples. 

Thermal Demagnetiser 

For more information contact: 

Leonie Maré, Geophysics Unit 

+27 (0)12 841 1416 

leoniem@gescience.org.za 





Hired, Fired and Retired…… Lief en Leed. 

From the Council for geoscience: - by Janine Cole. 

Quite a few new people have joined the Geophysics Unit at the Council for 

Geoscience over the past year. Peter Nyabeze and Emmanuel Chirenje, both 

originally from Zimbabwe, joined last year. Earlier this year Dr. Abera Tessema came 

to the Unit from the University of Venda. He specializes in potential fields. Melvin 

Sethobya and Lebogang Ledwaba are both young scientists who finished their 

studies and started to work at the CGS. Melvin is busy with a BTech at TUT, while 

Lebogang finished his BSc(Hons) at Wits. Marinda Havenga became mother for the 

second time in the beginning of this year. Henk Coetzee from the Environmental 

Geosciences Unit obtained a PhD from Wits University recently. 

Congratulations Henk!.....from SAGA( ed.) 

From the CSIR Applied Geoscience: - by Stefaans du 

plessis. 

Phetla Sefara (TUT) has joined the CSIR borehole radar team as an intern Borehole 

Radar Interpreter. 

Partene Pemengoye (TUT) (depending a student work permit application) will also 

soon join the CSIR borehole radar team as a Borehole radar interpreter. 

Stoffel Fourie has graduated with his PhD qualification at the University of Pretoria: 

Well done and congratulations Stoffel! 

Pieter Ewald Share is a CSIR bursary student and has spent 3 months on the 

SAMTEX field work programme, gaining valuable experience. Pieter Share will also 

be going to Ireland to DIAS to pursue his MSc studies (registered at Wits under Sue 

Webb) and hopefully continue on to complete a PhD as well. 

Ilze Janse van Vuuren (Tukkies geophysics student) is working part time for the CSIR 

and will be doing her honours in geophysics at Wits during 2009. 





The Department of Geological Survey 

Botswana (DGS): - by Hudson Ngwisanyi. 

MISSION 

The Department of Geological Survey (DGS) exists to advance knowledge on the 

earth resources of Botswana and to advice government and public on their 

sustainable utilization to the benefit of all. This is done by acquiring, archiving, 

interpreting and disseminating geo-science information on Botswana in order to 

facilitate: 

1. The speedy discovery and development of mineral and water resources for 

sustained economic growth, heath and safety, and 

2. Sustainable land resources utilization and the use of best practices for 

environmental upkeep and protection. 

Institutional Framework 

The DGS was established in 1948, primarily to address water supply challenges. It 

later grew from a focus on water only to include minerals and coal. This has been the 

focus since, with a lesser emphasis on coal. 

At present there are six primary operational divisions driving the mandate of the 

department. These are Regional Geological Mapping, Economic Geology, 

Hydrogeology, Geophysics, Environmental and Engineering Geology, and National 

Geoscience Information Centre. These are supported by the Chemistry and Mineral 

Dressing laboratories, Cartography and Drilling Sections. 

The DGS is directly responsible for gathering, assessing and disseminating data 

related to rocks, soils and minerals. To fulfil this responsibility, the DGS administers 

the concession of mineral prospecting rights to companies and individuals. It also 

undertakes regional geological, geophysical and geochemical mapping, and mineral 

potential studies. 

In the water sector the DGS undertakes regional groundwater investigations, 

assessment of groundwater, do recharge studies, monitoring of water levels and 

chemical changes within aquifers. Such information is used by the agricultural sector 

as well as the water authorities. 

The environmental and engineering geology sections are fairly new. It was 

established to address the numerous requests on environmental and geotechnical 

issues in Botswana. 

Notable Achievements 

Provision of geological maps at various scales to exploration companies has led to 

discoveries of economic mineral deposits including vast quantities of coal. Figure 1 

shows the level of exploration activity in Botswana as evidenced by the number of 

exploration licenses granted for diamonds. 





Figure 1: Mineral Concessions Map of July 2008 

In 2002 the DGS initiated a project called “Coalbed Methane and Karoo Basin 

Stratigraphic Project” whose objective was to establish a database on stratigraphy 

and develop a correlation system that characterizes the coal-bearing sedimentary 

rock sequence of the Kalahari Karoo Basin of Botswana. Two deep boreholes were 

drilled and one of them indicated the existence of coal bed methane. This was 

enough to encourage private sector exploration for CBM and the result is a number 

of mineral concessions granted for coal and CBM exploration. 

Identification of groundwater resources for human, livestock and mining continued. 

High resolution aeromagnetic data covering the entire country have been collected 

(figure 2). About 80% of Botswana is now covered with airborne magnetics at 200- 

250 metre lion spacing and 80 metres flying height. Indeed the data has been used 

by the private sector and this has led to the discovery of kimberlite pipes and 

generated several mineral exploration targets. 

Industrial mineral evaluation has been undertaken resulting in the establishment of 

some brick manufacturing factories. 





Figure 2: Aeromagnetic Anomaly Map of Botswana 

Current and Future Activities 

The Molopo farms complex project was started in 2001 with the overall aim of 

evaluating the Mineral Potential of the complex for PGM’s. A significant portion of the 

world’s reserves for platinum group minerals is hosted within the Bushveld complex 

in South Africa of which the Molopo farms complex is believed to be its offshoot. 

Interpretation of high resolution aeromagnetic data has led to a better understanding 

of the geology of the area. Soil geochemical sampling has been done over the area. 

Currently the department is doing follow-up geophysical and geochemical surveys 

over anomalous areas. 

The DGS will embark on projects to identify, assess and facilitate exploitation of 

industrial minerals and other commodities. This will benefit the local construction 

industry as well as communities and individuals. Because these projects are aimed at 

the small investors they will be carried through to the techno-economical evaluation 

stage and initiation of small scale mining so as to minimize risks for the miners 

(especially citizens). 

Regional geophysical surveys will be conducted over mafic, ultramafic and granitic 

complexes to assess their mineral potential. This will comprise a high resolution 

aeromagnetic survey over the Nossop-Ncojane block and the rest of the country, 

geochemical surveys over selected areas, airborne electromagnetic survey, deep 

seismic and subsequent drilling over selected targets. This will contribute to the 

search and discovery of mineral resources and provide baseline data. Hence the goal 





is to attract exploration companies to explore for minerals in this hitherto unexplored 

area. 

Assessment of kimberlite/ diamond exploration techniques will also be undertaken. 

This project is aimed at generating targets for kimberlite diamond exploration through 

systematic evaluation of exploration techniques, understanding of the source of 

indicator minerals of kimberlites in various provinces in Botswana (e.g Orapa and 

Kweneng areas) as well as structural implications to the emplacement of kimberlites. 

This will foster diamond exploration and enhance diamond discovery which 

subsequently will lead to sustainability in diamond aggregation and cutting in 

Botswana. 

Challenges 

The DGS has faced an unprecedented rate of staff turnover in the past 5 years as 

employees have left for better remuneration in the private sector. This has led to 

diminished organisational effectiveness and project implementation capacity. The 

department lacks some critical skills especially in seismology and geochemistry. 

A true physics story 

The following concerns a question in a physics degree exam at the University of 

Copenhagen: - "Describe how to determine the height of a skyscraper with a 

barometer." 

One student replied: 

"You tie a long piece of string to the neck of the barometer, then lower the barometer 

from the roof of the skyscraper to the ground. The length of the string plus the length 

of the barometer will equal the height of the building." 

This highly original answer so incensed the examiner that the student was failed 

immediately. He appealed on the grounds that his answer was indisputably correct, 

and the university appointed an independent arbiter to decide the case. The arbiter 

judged that the answer was indeed correct, but did not display any noticeable 

knowledge of physics. 

To resolve the problem it was decided to call the student in and allow him six minutes 

in which to provide a verbal answer which showed at least a minimal familiarity with 

the basic principles of physics. 

For five minutes the student sat in silence, forehead creased in thought. The arbiter 

reminded him that time was running out, to which the student replied that he had 

several extremely relevant answers, but couldn't make up his mind which to use. On 

being advised to hurry up the student replied as follows: 





"Firstly, you could take the barometer up to the roof of the skyscraper, drop it over 

the edge, and measure the time it takes to reach the ground. The height of the 

building can then be worked out from the formula H= 0.5g x t 2 . But bad luck on the 

barometer. 

"Or if the sun is shining you could measure the height of the barometer, then set it 

on end and measure the length of its shadow. Then you measure the length of the 

skyscraper's shadow, and thereafter it is a simple matter of proportional arithmetic to 

work out the height of the skyscraper." 

But if you wanted to be highly scientific about it, you could tie a short piece of string 

to the barometer and swing it like a pendulum, first at ground level and then on the 

roof of the skyscraper. The height is worked out by the difference in the gravitational 

restoring force T = 2 *π*√ (l / g)." 

"Or if the skyscraper has an outside emergency staircase, it would be easier to walk 

up it and mark off the height of the skyscraper in barometer lengths, then add them 

up”. 

"If you merely wanted to be boring and orthodox about it, of course, you could use 

the barometer to measure the air pressure on the roof of the skyscraper and on the 

ground, and convert the difference in millibars into feet to give the height of the 

building." 

But since we are constantly being exhorted to exercise independence of mind and 

apply scientific methods, undoubtedly the best way would be to knock on the janitor's 

door and say to him 'If you would like a nice new barometer, I will give you this one if 

you tell me the height of this skyscraper'." 

The student was Niels Bohr, the only Dane to win the Nobel prize for Physics. 





Shallow high resolution seismic surveys: Resolution and 

frequency content is everything – A simple tool to help with survey 

planning. 

C.J.S. Fourie, Geophysicist: Applied Geoscience, CSIR, South Africa 

Telephone: +12-841-3395, Fax: +86-602-9765, E-mail: sfourie@csir.co.za, 

Address: Post Box 395, Pretoria, 0001, South Africa 

C.L. van Dam, Geophysicist, 63 Van Riebeeck Avenue, Lyttleton, South Africa 

Telephone: +12-664-3430, E-mail: chris.vd@cybersmart.co.za. 

ABSTRACT 

All electromagnetic geophysical methods, but the frequency domain methods 

in particular, depend on the skindepth as a guide to the depth of investigation or 

penetration from the surface. By definition the skindepth is the distance where the 

initial amplitude of the electromagnetic wave attenuated by 1/e or 67%. This measure 

is influenced by the physical properties of the subsurface and uses the resistivity, the 

angular frequency (ω) of the electromagnetic field and the magnetic permeability (µ). 

By using more than one frequency, different depths of penetration are achieved, 

which allows one to obtain information from the consecutive different layers of 

geology. The same is true of seismic waves which also attenuate with distance and 

time. The attenuation also depends on the properties of the subsurface, of which the 

frequency (f), velocity (v) and the Q-factor are the most important. Similar to the 

electromagnetic method, depth of penetration can be manipulated in a way by 

controlling the frequency of the input wave. This information can be used in 

conjunction with this spreadsheet to aid the geophysicist in designing shallow high 

resolution seismic surveys to achieve maximum resolution and penetration. This 

Excel spreadsheet is available free from the authors. 

INTRODUCTION 

Electromagnetic systems and the frequency domain electromagnetic (FDEM) 

systems in particular, utilise more than one frequency to obtain information from the 

subsurface at different depths (e.g. Apex Max-Min system). These frequency domain 

electromagnetic systems utilise an entity called the skin depth (Sheriff, 1991, Telford, 

1986). The definition of the skin depth is the effective depth of penetration of an 

electromagnetic plane wave up to the point where it is attenuated to 1/e of its original 

amplitude. The electromagnetic skin depth is given by equation 1. 

δ = 

2σ 

µω 

(1) 





Where 

σ = resistivity 

µ = permeability 

ω = 2Πf = angular frequency. 

The skin depth is largely controlled by the frequency used. As a rule, lower 

frequencies, allow for deeper depths of investigation. The conductivity also plays an 

important role. Lower conductivities (higher resistivities) result in deeper depths of 

investigation. High conductivities have a shielding effect on the electromagnetic 

waves. 

This approach is also employed by using certain seismic or sound waves 

(Nasseri-Moghaddam et.al, 2005). They used the frequency dependency of the 

surface waves to determine the depth of shallow voids. The penetration of the 

surface seismic waves of P-waves and S-waves, the so-called Rayleigh and Love 

waves definitely have these properties (Thorne and Wallace, 1995, Yilmaz 1989). 

All seismic waves undergo attenuation. The loss of amplitude is exponential 

of a seismic wave through an imperfect medium (Waters, 1981). This means that the 

ratio in which the amplitude decays is a constant, which is called the logarithmic 

decrement (δ). The specific logarithmic decrement is called the Q-factor. Together 

with the velocity (v) and the frequency (f) one can calculate an attenuation constant 

(α) for each situation. 

Shallow high resolution seismic surveys are routinely used in near surface for 

mineral exploration and in environmental surveys to detect small structures and 

lithologies for pollution detection purposes. In this paper a very simple spreadsheet 

is introduced to aid in the planning and design of shallow high resolution seismic 

surveys, when all of the important parameters are taken into account. 

ATTENUATION OF SEISMIC WAVES 

Seismic waves undergo attenuation, even when the waves have very small 

amplitudes. This happens because the subsurface medium is not perfectly elastic 

and because the earth is strong but not critically damped (Fourie, 2005, Fourie et al, 

2004). The deviations from Hooke’s law are usually small and the approximations of 

the elastic wave theory are sufficient (Fourie, 2005 and Waters, 1981). 

Friction arising from the sliding of grains or crystals against each other is 

widely acknowledged as the most probable mechanism of energy loss, and the term 

“solid friction” is frequently used (Waters, 1981). 

The symbol Q is used to indicate the rock quality for seismic wave propagation, 

analogue to the electrical circuit situation. For the “solid friction” model the 

attenuation coefficient (α) is dependant on the following properties of the seismic 

wave: 

• Frequency (f) 

• Velocity (v) 





• Quality factor (Q) and 

• Logarithmic decrement (δ), where δ = Π/Q 

The attenuation constant can thus be expressed as the following (Waters, 1981): 

α = 

Πf 

Qv 

(2) 

The attenuation is exponential. To calculate the distance that the wave must 

travel in a specific environment before it is reduced to a certain amplitude is given by 

(Waters, 1981): 

e 

−αx 

= 

A 

R 

(3) 

Where 

α = attenuation constant 

x = distance travelled by the wave 

A R = Resultant amplitude 

These relationships in equations 2 and 3 were used to develop a simple 

spreadsheet to aid the scientist with seismic survey design. 

SPREADSHEET DESCRIPTION 

During any reflection seismic survey some survey planning has to be done to 

ensure the success of the survey. Usually the size and the depth of the target have 

the most influence on the planning. This will determine the frequencies to be used. 

The attenuation also depends on the Q-factor of the different lithologies of the 

subsurface. 

Q-factor information of rocks is very incomplete. As a rule of thumb, the Q- 

factor for rock is usually estimated as being 1% to 3% of the velocity (Sheriff, 1991). 

Our experience is that it could be a low as 0.5% to 0.25% if the weathered layer with 

the unconsolidated material is investigated. 

During the data acquisitioning process of any normal seismic survey, there is 

an offset between the source and the receiver (Figure 1). The maximum allowed 

angle is 45 degrees; otherwise more surface waves will be generated with little 

penetration, which is energy insufficient. This angle at 45 degrees is maximum ray 

path that should be used for a survey. Depending on the physical properties of the 

subsurface and the acquisition parameters such as the frequency, velocity and the 

Q-factor, a maximum target depth can be estimated using the spreadsheet. The aim 

of all processing is to obtain a zero offset or stack section (Figure 2). The 

spreadsheet allows for this option. 





Figure 1: Schematic diagram of the seismic data acquisitioning process. 

Although the spreadsheet can be adapted and customised, it currently allows for 

different options. These include: 

• The maximum two-way ray path distance at 45 0 . 

• The two-way ray path distance at zero offset. 

• The one way ray path distance at zero offset 

Amplification and attenuation in electronics, acoustics, seismic instrumentation 

and other fields are often described by means of a logarithmic rather than linear 

scale, because the range of values of interest is very large. The notion of decibels 

was first used in comparing signals of sound, and in this case the desired 

comparison is between intensities of sound. Thus if two signals have intensities I 1 

and I 2 respectively then the intensities are compared using the formula 10 log(I 1 /I 2 ). 

Now the intensity of a sinusoidal signal having fixed amplitude and frequency is 

proportional to the square of its amplitude. 

Let A 1 and A 2 be the amplitudes of two sinusoidal signals and I 1 and I 2 their 

intensities. 

Then I 1 ∝ A 1 2 and I 2 ∝ A 2 2 implies I1 = kA 1 2 and I 2 = kA 2 2 for some constant k. 

(Revise proportion.) 

Then 10 log (I 1 /I 2 ) 

= 10 log (kA 1 2 /(kA 2 2 )) 

= 10 log (A 1 2 /A 2 2 ) 

= 10 log (A 1 /A 2 ) 2 , 

= 10 [2log (A 1 /A 2 )], (from log a b = b log a) 

= 20log (A 1 /A 2 ). 

In this way the expression 20log (A 1 /A 2 ) has come into use where amplitudes of 

voltage or current are under consideration. 





Figure 2: Schematic of the Zero Offset principal. 

This spreadsheet thus allows the user to calculate the loss of amplitude in 

decibels (dB). This is important because it gives an indication of the amplification 

properties a seismograph must have to record the data within acceptable noise levels 

(Figure 3). It is often referred to as the gain. 

Figure 3: Spreadsheet operations to calculate amplitude, energy and gain losses for different 

parameters. 





SPREADSHEET OPERATION 

Using the spreadsheet is quite easy. It calculates penetration depths for five 

(5) different frequency options (Figure 4). On the left side is the amplitude ratio and 

on the right side is the gain in Decibels (dB) and the remaining energy of the wave. 

At the bottom of the table the operator can change the wave velocity (v), the 

frequency and the Q-factor. It is thus possible to compare penetration depths for the 

same frequencies using different parameters, or to make comparisons between 

different frequencies and keeping the other parameters constant. 

Figure 4: Penetration depths as calculated by the spreadsheet. 

Five different curves are displayed where the percentage of energy against 

the penetration depths are displayed. The operator can also calculate the 

penetration depths by adjusting the wave paths. For a maximum two-way path 

distance of 45 0 the factor is 2.38. A zero offset two-way path is calculated with a 

factor 2 and a one way path distance is calculated at a factor 1. 

DISCUSSION 

The development of this spreadsheet was done primarily to aid the 

geophysicist with the design of shallow high resolution seismic reflection surveys 

where resolution of small faults and structures are important. Attenuation of seismic 





waves is influenced a lot by the physical properties of rocks, which have a large 

influence on the wave velocity and the Q-factor. By varying these parameters the 

effects of the changes are immediately apparent on the graphs. 

Simple aid and prediction tools to help the geophysicist in designing surveys 

are not so easy to find. It is proposed that this simple spreadsheet discussed in this 

paper can meet this requirement in one aspect of small seismic surveys, by giving the 

geophysicist the possibility to quickly vary input parameters, which will aid and guide 

him to better predict survey specifications. This spreadsheet is available free from 

the authors. 

REFERENCES 

Fourie, C.J.S., Cole, .P and Van Rooy, L., 2008, Three-dimensional in-situ small 

movement elasticity modulus estimations using a seismic technique: Africa 

Geoscience Review, Vol.15, No.1, pp.1-10. 

Fourie, C.J.S., 2005, Three-dimensional in-situ subsurface density estimations using 

a seismic technique: Africa Geoscience Review, Vol.12, No.1&2, 2005. 

Fourie, C.J.S. and Cole, P. 2004, Development of an In-situ Density Geophysical 

method using a Seismic Technique: Report 2004-0095, Council for Geoscience, 

Pretoria, South Africa. 

Fourie, C.J.S. and Cole, P. 2004; Three – dimensional In-situ subsurface Density 

estimations using a Seismic Technique: Geoscience Africa, 2004, Abstracts. 

(Johannesburg, South Africa). 

Griffiths, D.H. and King, R.F. 1969; Applied Geophysics for Engineers and 

Geologists: Second Edition, Pergamon Press. 

Kearey, Phillip and Brooks, Michael, 1991, An introduction to Geophysical 

Exploration: Second Edition, Blackwell Scientific Publications. 

Kibble, T.W.B. 1985, Classical Mechanics: Third Edition, Longman Scientific & 

Technical Press, London. 

Nasseri-Moghaddam, A. et. al, 2005, A New Quantitave Procedure to Determine 

the Location and Embedment Depth of a Void Using Surface Waves: Journal of 

Environmental & Engineering Geophysics, Vol.10, Issue 1, March 2005. 

Sears, Zemansky and Young, 1987, University Physics: (Seventh Edition). 

Massachusetts, Addison-Wesley Publishing Company. 

Sheriff, R.E., 1991, Encyclopaedic Dictionary of Exploration Geophysics: Third 

Edition, Society of Exploration Geophysicists, Tulsa OK, U.S.A. 

Telford, W.M., 1986, Applied Geophysics: Cambridge University Press. 

Thorne, L., and Wallace, T. C. 1995, Modern Global Seismology: San Diego, 

Academic Press. 

Waters, K.H., 1981, Reflection Seismology, A tool for energy resource exploration: 

Second edition, John Wiley & Sons, New York. 

Yilmaz, O. 1989, Seismic Data Processing: Society of Exploration Geophysicists, 

U.S.A.

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