NEWSIn the news this issuen Chinaman Creek Limestonen National Rock Garden updaten IGCP FundingNational Rock Garden —Chinaman Creek LimestoneGSA Rock <strong>of</strong> the Month — September 2012This new TAG feature will highlight some <strong>of</strong> <strong>Australia</strong>’s most interestingrocks — rocks that are spectacular or scientifically, economically orculturally significant, <strong>and</strong> potentially likely to be featured in the NationalRock Garden (NRG). Please let us know if you think they should or shouldnot be included. The NRG is a project initiated by GSA to celebrate thegeological heritage <strong>of</strong> <strong>Australia</strong>, to build a unique <strong>and</strong> fascinatinggeoscience education facility for the 165 000+ school students from allover <strong>Australia</strong> that visit their national capital each year. The NRG aimsto promote the role that geology plays in the lives <strong>of</strong> all <strong>Australia</strong>ns.If you have a passion for or interest in the geosciences, or theeducation <strong>of</strong> our children, or have drawn a livelihood from industriesderived from our rocks, please help us establish a globally uniquecelebration <strong>of</strong> the geology <strong>of</strong> <strong>Australia</strong> in our nation’s capital.We have selected the Devonian Chinaman Creek Limestone from theBroken River Province <strong>of</strong> North Queensl<strong>and</strong> as our first ‘Rock <strong>of</strong> theMonth’ because it is spectacular, acquirable <strong>and</strong> displays a significantcollection <strong>of</strong> fossils, many yet to be documented. Are there moreimportant Devonian fossiliferous limestones available that are equallyor more spectacular?The Chinaman Creek Limestone is a major component <strong>of</strong> the BrokenRiver Group that formed a broad shelfal succession in the northern part<strong>of</strong> the Graveyard Creek Subprovince, southwest <strong>of</strong> Greenvale in northQueensl<strong>and</strong>. The formation is up to 790 m thick <strong>and</strong> consists largely <strong>of</strong>clastic limestone intervals up to 250 m thick <strong>of</strong> very thick to thin-beddedcalcirudite <strong>and</strong> calcarenite <strong>and</strong> sporadic, thin interbeds <strong>of</strong> calcareousmudstone, siltstone <strong>and</strong> s<strong>and</strong>stone. More substantial siliciclasticintervals <strong>of</strong> lithic s<strong>and</strong>stone, siltstone <strong>and</strong> mudstone, <strong>and</strong> rareconglomerate up to 100 m thick are interlayered.Reefal limestone intervals up to 30 m thick <strong>and</strong> 2 km long are locallyrepresented in the unit, mainly in its lower parts. These are mainlystromatoporoid–heliolitid–rugose coral framestone, with prominentheads <strong>of</strong> the rugosans Endophyllum <strong>and</strong> Phillipsastraea in the upper <strong>and</strong>lower parts <strong>of</strong> the succession, respectively.Bioclastic components are largely <strong>of</strong> stromatoporoid or corallinedebris (with Amphipora characteristics), but fragments <strong>of</strong> crinoids,brachiopods, bivalves, gastropods, ostracods <strong>and</strong> calcareous algae arealso represented. Corals <strong>and</strong> stromatoporoids are locally found in growthpositions <strong>and</strong> large valves <strong>of</strong> Stringocephalus <strong>and</strong> megalodont bivalvesare prominent in the upper part (Withnall, 2012).Devonian Chinaman Creek Limestone from north Qld, also featuring LindaMcClure, Marketing Manager, North Queensl<strong>and</strong> Marble Pty Ltd. The limestoneis quarried near the old P<strong>and</strong>anus Creek homestead <strong>and</strong> is being sawnon-site <strong>and</strong> transported to Townsville for shipment overseas. The companyspecialises in rare <strong>and</strong> unique ‘top end <strong>of</strong> the market’ dimension stones forthe international market. Image courtesy Rob Cameron (North Queensl<strong>and</strong>Marble Pty Ltd), 2012.Megalodont bivalves (superfamily Megalodontoidea) are unusual<strong>and</strong> very distinctive fossils <strong>of</strong> the middle Paleozoic to early Mesozoic.Many species are large <strong>and</strong> thick-shelled, <strong>and</strong> have great preservationpotential. So, it is surprising that, although these clams had a largelycosmopolitan distribution in the Silurian <strong>and</strong> Devonian <strong>and</strong> were locallyvery abundant, their taxonomy <strong>and</strong> paleoecology are poorly known. Theywere inclined mud resters, oriented with sagittal plane vertical, <strong>and</strong> grewpartly submerged in, or on top <strong>of</strong>, generally firm lime mud substrates,in tropical shallow water (de Freitas et al, 1993).Megalodont bivalves are predominant in the spectacular slab <strong>of</strong>limestone shown in the photograph accompanying this article.Most <strong>of</strong> the specimens in the slab represent slices through the ‘beak’part <strong>of</strong> articulated shells, many still in growth position. Others showdifferent sections <strong>of</strong> the shell — still the ‘beak’ area but sliced moreobliquely so that a small part <strong>of</strong> the valves distal to the ‘beak’ are alsoshown (they look like spines). The shells were projecting at an angle fromthe sea-floor (hence the oblique sections) as the slab has been cut atan angle to bedding. Bits <strong>of</strong> sliced valve away from the thick beak regionshow as much thinner curved white lines (Henderson, 2012).JOHN BAINCurator NRGR E F E R E N C E Sde Freitas, Brunton <strong>and</strong> Bernecker 1993 Silurian Megalodont Bivalves <strong>of</strong> theCanadian Arctic <strong>and</strong> <strong>Australia</strong>: Paleoecology <strong>and</strong> Evolutionary Significance. Palaiosvol. 8, p. 450–464.Henderson, Bob (James Cook University) pers. comm. to Rob Cameron May 2012.Withnall, Ian (GSQ), pers. comm. July 2012.TAG September 2012| 23
NRG updateThe news is all good for the NRG.On Friday 3 August we were advised by the <strong>of</strong>fice <strong>of</strong> Assistant Treasurer(The Hon David Bradbury MP) that the National Rock Garden Trust’s applicationto be placed on the Register <strong>of</strong> Environmental Organisations had been approved,effective from 2 August 2012. This approval means that the NRG qualifies forDeductible Gift Recipient (DGR) status — in other words, donations to the NRGare now tax deductible!With the NRG having a display booth at the 34th International <strong>Geological</strong>Congress in Brisbane 5-10 August, news <strong>of</strong> DGR status could not have come ata better time. With nearly 6 000 attendees the IGC booth was a great way topublicise the NRG, both nationally <strong>and</strong> internationally. Cec Murray, from theQueensl<strong>and</strong> Division, manned the booth throughout the week, with help fromBrad Pillans - many thanks, Cec.Also, the NRG website is now ‘live’ – please visitwww.nationalrockgarden.org.au <strong>and</strong> let us know what you think.The website will grow over time <strong>and</strong> will be the primary source <strong>of</strong> informationon the NRG. And feel free to make a donation!BRAD PILLANSGSA member Cec Murray at the National Rock Garden booth withrocks from around <strong>Australia</strong> (thanks to Geoscience <strong>Australia</strong>,Xstrata Copper Exploration, Kimberley Stone Zebra Rock Mine <strong>and</strong>the <strong>Geological</strong> Survey <strong>of</strong> Queensl<strong>and</strong>). Image courtesy Brad Pillans.IGCP funding – September 2012IGCP <strong>Australia</strong>n participants: funding for conference attendance!!Each year the <strong>Australia</strong>n Committee <strong>of</strong> the International GeoscienceProgram <strong>of</strong> UNESCO receives funding to support conference attendancefor <strong>Australia</strong>n participants in International <strong>Geological</strong> CorrelationProgram (IGCP) projects. The grants range from $2000 to $4000.To apply, request an application form from the Chair <strong>of</strong> the Committee,Pr<strong>of</strong>essor Patricia Vickers Rich (pat.rich@monash.edu). Successfulapplicants need to demonstrate that their attendance is directly linkedto the aims <strong>of</strong> one or more currently active IGCP projects with whichthey are associated.Please apply — application is not complex <strong>and</strong> turnaround time isgenerally no more than one month.24 |TAG September 2012
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