TAG 166 - Geological Society of Australia

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the influence of the Messinian salt onstructuring. Surprisingly there is a recentpaper in Geological Society of London SpecialPublication 363 devoted to strain in theLevant Basin associated with four majorhalite detachments, which are interpretedfrom 3D seismic data.Geology discussed in the volume covers theoffshore Levant Basin (eastern corner of theMediterranean) and the adjacent platform onthe Arabian and African Plates, and it dealswith late Paleozoic and early Mesozoic basindevelopment and late Cretaceous–Cenozoicdeformation associated with the closure ofTethys. The Mesozoic eastern margin of thebasin and its shelf edge are identified nearthe present-day Israeli coastline as a narrowtransition zone extending from northernEgypt to western Lebanon. Late Cretaceousconvergence of Afro–Arabia with Asiaresulted in the north-dipping subductionzone at present-day Cyprus and southernTurkey. This event is marked in the LevantBasin by inversion of existing normal faultsand local deformation with pronouncedpaleorelief, also the development ofsyndepositional basins and swells resultingfrom growth faulting. There is thus a widerange of sedimentary environments rangingfrom outer shelf to deltaic–fluviatile deposits.The last major tectonic event is recorded asthe breakup of the African and Arabiancratons with the development of the DeadSea transform. Sinistral movement on thisboundary amounts to about 100 km. In brief,the Levant Basin is a structure of considerableinterest due to its tectonic setting andthe influence of major plate interactionssince the breakup of Gondwana.R DALGARNObdalgarno@internode.on.netShaping a Nation: a geologyof AustraliaR Blewett (Chief Ed)Geoscience Australia & ANU Press, 2012,571 pages, $70.00ISBN 9781922103437If the 34th IGC in Brisbane (August 2012)achieved nothing except the related writingof this book, we should be grateful. Theunusual structure of the book probably owesits form to the Editorial Board and ChiefEditor, Richard Blewett. The 11 chapters werewritten by 57 authors, some making multiplecontributions.This large tome (hard cover printed on artpaper, weighing almost 8 kg) is, at the sametime, both fascinating and annoying. Thelandscape format is well adapted to its manyfine maps, photos and figures, although thelocalities of some photos are not identified.The editors state, “this book is not anothergeology of Australia with the rocks, mineralsand fossils catalogued through time”. Ratherit deals with “Australian geology: thefoundation that shapes the people”. Thisconcept is imaginatively brought out inFigure 1.1, and is presented again in adifferent form, encircled by ‘Earth SystemScience’, in Figure 11.1.The titles of the 11 chapters, too, give an ideaof the book’s ‘philosophy’: Australia and theAustralian people; Australia in space andtime; Living Australia; Out of Gondwana;Old, flat and red — Australia’s distinctivelandscape; Living on the edge — waterfrontviews; Groundwater — lifeblood of thecontinent (perhaps the most accessibletechnical chapter); Foundations of wealth —Australia’s major mineral provinces;Sustaining Australia’s wealth — economicgrowth from a stable base; the interesting‘speculative’ Deep heat — Australia’s energyfuture?; and Advance Australia Fair.The relationship to the Australian people isstrongly maintained, most notably throughmentions in chapters one, two, seven andeleven. Recognition is given in places to thecontribution of the Aboriginal people, notablyin their respect for country.An important topic discussed is the questionof the age of Australian landscapes. Whilethere seems to be agreement that manyAustralian landscapes presently visible areold, opinions differ, even within a singlechapter as to: (1) whether they haveremained exposed since formation,weathering slowly and eroding even slower;or (2) they have been protected by thick coverand owe their appearance today largely touplift and exhumation. In chapter 6 (p 289)there is mention of “minimal landformerosion, … a strong feature of the dry, flatregions of southern Australia”. What does onemake then of the discussion of apatite fission(p 260 and Box 5.5), which is said to provide“estimates of denudation over large areas”?Figure 5.23 presents the results of suchcalculations, Australia-wide. This figureseems to call for almost catastrophic activityto remove 4 km of rock adjacent to areasfrom where only 2 km has gone. SouthAustralia, as depicted, is one such region. Thelocalities in all states and territories (notablyQueensland) showing nearly zero removal,often sit somewhat uncomfortably close toregions of claimed extreme denudation.Figure B5.5b by Scott and Pain (2008) seemsto absolutely contradict Figure 5.23. For thepresent I will stick with S & P!Editing and proof-reading have been verywell done, but in a volume of this size andcomplexity, a few errors have escaped notice.Box 2.2, p 67 incorrectly credits EdgeworthDavid and his party with reaching the SouthMagnetic Pole. Box 4.3 (p 196) uses‘palaeography’ for ‘palaeogeography’.Figure 5.10a (p 240) suggests that Pain(1985) ‘defined’ the ‘Great Escarpment’, butit is surely Ollier (1982), as referred to onseveral figures. Box 5.2 (p 246) puts theMurray–Darling headwaters all in CentralQueensland, but they are not.A new matter for me was the appearance ofcaveats accompanying some illustrations.The small print accompanying the data onFigure 4.11 (similar for other figures) puts theonus on the reader to check the informationbefore using it, presumably for economicpurposes. Has the legal world gone over thetop?In terms of grammatical use, the volumeproves that the ‘infinitive is well and trulysplit’!Geologists of all levels will gain much fromthe book, although perseverance will oftenbe needed. Local terminology will appeal toAustralian readers, but overseas readersmight well be puzzled by some material,including occasional typical Australianself-deprecating remarks.The book is a fine, if demanding volume,showing how important geology has been,and continues to be, for the Australianpopulation. Although somewhat too proselytisingat times, it deserves wide circulation.Martin Ferguson, the present Minister forResources, Energy and Tourism, endorsesthe volume enthusiastically, writing, “Thisexciting book demonstrates the fundamentalimportance of the study of Earth Sciences toour society.” Well said, sir!DAVID BRANAGANR E F E R E N C EScott K & Pain CF (eds) 2008. Regolith Science, CSIROPublishing, Melbourne.TAG March 2013| 47
Geology of QueenslandP Jell (Ed)Department of Natural Resources and Mines(DNRM) and Geological Survey of Queensland,970 pagesThis brilliant book has been written by teamsof geoscientists from the Geological Survey ofQueensland, universities and industry. It isexceedingly well edited by Peter Jell.There are two parts to the volume. The firstand larger part describes the hard-rockgeology that underlies younger basins andrecent cover. These provinces range in agefrom the Precambrian rocks of the NorthAustralian craton (chapter 2) through theNeoproterozoic to Paleozoic Thomson Orogen(chapter 3), which is largely obscured by theEromanga Basin, the newly named PaleozoicMossman Orogen (chapter 4) and thePaleozoic to Mesozoic New England Orogen(chapter 5) and related Carboniferous-Permian granites of the Kennedy IgneousAssociation (chapter 6).The second part of the volume brings us upto the present day by describing youngerrocks (post orogenic Mesozoic basins andmagmatism, chapter 7), Paleogene andNeogene (chapter 8) and Quaternary(chapter 9). It even includes impact structuresand meteorites (chapter 14). But moresignificantly, it describes what one does withthese rocks and why they underpin theeconomic development of Queensland.Mineral and energy resources are discussed inchapter 10, engineering geology in chapter12 and groundwater resources in chapter 13.Chapter 15 briefly introduces the reader tothe geological heritage of Queensland anddiscusses preservation as well as geotourismand understanding landscape evolution.Seismicity is discussed in chapter 11. Thisfocuses on databases and spatial distribution.To my mind it would have been enhanced byplacing it in a structural context. All this isunderpinned by an exhaustive reference listof 117 pages!This book is the most up-to-date summary ofthe geological development of Queenslandover the last 1870 million years. This story ofQueensland’s evolution is told mainly in termsof the logical development of differentstratigraphic units on top of one another,although the description of the Mt IsaProvince is clearly told in terms of tectonicevents based on a sequence of eventsencompassing (super)basin formation, crustalextension and crustal contraction. Clear mapsand time–space plots help clarify the geology.All figures are in colour and this is a tremendoushelp. The last parts of the ‘hard-rock’chapters discuss different tectonichypotheses, so that there is a welcome clearsubdivision between ‘facts’ and ‘arm-waving’.This is a fantastic book: it’s the one I’ve beenwaiting for because, to be honest, I’ve alwayshad trouble visualising the subdivision intodifferent tectonic elements and how theNeoproterozoic to Mesozoic elements ofQueensland geology fit into the coeval rocksof more southern parts of the Tasmanidesof eastern Australia. So now we have aninternally consistent set of tectonic elementsthat underlie Queensland, as well as definedboundaries between different provinces andsubprovinces. All this is shown in Figure 1.3,which is a superb structural framework mapshowing older provinces and younger (overlapping)basins interpreted beneath theblanketing Jurassic–Cretaceous Eromangaand Surat Basins. I’ve stuck the map upabove my desk.On the map, the hierarchy is cratonicAustralia or orogens, then provinces, thensubprovinces. Basins are treated differently.Devonian–Carboniferous basins west of theNew England Orogen are given their ownnames, whereas those in the New EnglandOrogen are included in the Yarrol Province.From chapter 1, I’m not sure whether theDevonian–Carboniferous Burdekin Basin westof Townsville is part of the Charters TowerProvince of the Thomson Orogen, or liesabove it. And I didn’t really know that therewas an Iron Range Province in eastern Yorkpeninsular that may be part of the ThomsonOrogen or that there is a Cape York–OriomoProvince.Chapter 1 provides the background to theState’s geology, summarising the keyprovinces and looks forward to chapter 10,which discuses the mineral endowment. Italso discusses the history of geologicalactivity and mapping in the State.Given that Queensland is home to somepeople of fundamentalist persuasion, whocommonly wear maroon jerseys, as well assome of Australia’s most exciting dinosaursfinds, it is apposite that chapter 1 alsocontains significant data on the time scaleand how time is measured, with summaries ofdifferent dating techniques. Feature boxes,which are used in chapters 3, 4 and 8 topresent new data and interpretations, aremaroon in colour so perhaps all is well!I was most interested in the hard-rockchapters of the Tasmanides and somecomments on these chapters follow.Chapter 3 describes the Thomson Orogen.Most of this lies beneath the Eromanga Basin,so this orogen is described in two parts: anexcellent synthesis of outcropping parts, suchas in the Anakie and Charters TowersProvinces, together with synthesis maps ofdrillcores into the subsurface parts (basedlargely on Cec Murray’s 1994 paper). Interestingly,Devonian basins such as the Adavale incentral Queensland are not regarded as partof the Thomson Orogen, but as overlying it.This differs from the terminology used inNSW where the Thomson Orogen incorporateselements from the ?Neoproterozoicthrough to the Late Devonian. ChrisFergusson and Bob Henderson provide avaluable synthesis at the end of the chapter.Related to this, I note that the dynamicsignificance of the shallow-dipping S2foliation in the Anakie area is once againthought of as contractional rather thanextensional, based on a feature article byRobin Offler and others.Chapter 4 describes the Mossman Orogen.This I read with great attention since I’vebeen perplexed in the past by terminology,as well as boundary relationships to the southand internally. Interestingly, the orogen isrestricted in age to Silurian and Devonian andpresumably in area by their outcrop/subcropareas. This means that in places it overliessmall outcrops of Thomson Orogen. TheMossman Orogen is inferred to lie west of thepartly coeval New England Orogen, althoughlocally the eastern boundary is faultedagainst the Barnard Province of the ThomsonOrogen. Silurian Devonian granites thatlargely intrude the craton to the west arealso included in the Mossman Orogen. Thischapter contains great detailed descriptions,together with tectonic interpretations andsyntheses of the classic arguments about thetectonic setting of the Chillagoe Formationand Hodgkinson Group. Both argumentsare clearly presented here — the back-arcargument by Paul Donchak and the accretionarymargin model of Bob Henderson. It’s atribute to the editor that both sides of suchcontroversial and important topics get airplay.48 |TAG March 2013
Page 3 and 4: From the PresidentWelcome back from
Page 5 and 6: Society UpdateGovernance changesCom
Page 9 and 10: Society UpdateFrom the AJES Hon Edi
Page 11 and 12: Society UpdateEducation&OutreachIn
Page 13 and 14: A conference in 2014 is envisaged a
Page 15 and 16: NEWSIn the news this issuen NRG Roc
Page 17 and 18: It is proposed that an important el
Page 19 and 20: IGCP projects with Australian leade
Page 21 and 22: Ediacaran Golden Spike localityVisi
Page 23 and 24: Feature 1Feature 1Snowy Mountains H
Page 25: Tumut 2 tailwater tunnel during con
Page 31 and 32: Fossil hunting organised by Kronosa
Page 33 and 34: Fortunately for Paul Stumkat, he is
Page 35 and 36: Year 12 EES students from across WA
Page 37 and 38: Special Report 3Global warming and
Page 39 and 40: As indicated in the table accompany
Page 41 and 42: Ian Percival spoke on protecting an
Page 43 and 44: Books for reviewPlease contact the
Page 45 and 46: An introductory paper to the volume
Page 47: this land, and showing the richness
Page 51 and 52: O B I T U A R I E SSylvia Whitehead
Page 53: The Australian GeologistBackground

TAG 166 - Geological Society of Australia

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