Customising the geological timescale for use in Australasia
John R Laurie A , Daniel Mantle A , Robert S Nicoll A and James Ogg AGeoscience Australia
The APPEA Journal 49(1) 301-310 https://doi.org/10.1071/AJ08019
Published: 2009
Abstract
The global standard geological timescale (GTS 2004) is largely built around northern hemisphere datasets. Consequently, a large proportion of the biozones used in Australia were not included, thus hampering its implementation in the region. Previously, most of the Australasian biozonal schemes had been tied to the Australian Geological Survey Organisation timescale (AGSO 1996) but each of these needed to be recalibrated to tie with the updated and globally standardised GTS 2004. This process was complicated by the fact that several of the local biozonal schemes have been revised in the intervening period. The updates of Australian biozones to GTS 2004 compliance were accomplished using extensive literature searches as well as targetted reviews of some biozonal schemes. These recalibrated and amended schemes have now been included in Geoscience Australia’s Timescales Database, which acts as a core lookup table for numerous databases across the organisation.
In 2010, GTS 2004 will be replaced by an updated standard timescale. To facilitate this transition and other future revisions, Geoscience Australia’s Timescales Database is being revised to store the relationships between biozones and the geological timescale in a format that will allow essentially automatic, rather than protracted manual, updates.
A public visualisation software package, Time Scale Creator, is available on the web from the International Commission on Stratigraphy (ICS) to display user-selected intervals from an ICS database suite of over 20,000 biological, geomagnetic, sea-level, and other events with ages consistent with GTS 2004. Geoscience Australia (GA) has compiled a customised datapack for Time Scale Creator which includes most Australian biozonal schemes. In addition, Geoscience Australia is using the lithostratigraphic capabilities of this software package to generate basin biozonation and stratigraphy charts, which supersede those published nearly a decade ago.
John Laurie is a senior research scientist in Geoscience Australia and has a BSc (Hons 1) in geology from the University of Newcastle and a PhD in palaeontology from the University of Tasmania. After a brief period as a regional mapper in the Northern Territory Geological Survey in Alice Springs, he joined BMR (now Geoscience Australia) in 1982 as part of the Timescales project and subsequently co-edited the 1996 Australian Phanerozoic Timescale volume. He has over 80 publications to his name including co-authorship of two volumes of the Treatise on Invertebrate Paleontology. John is editor of the Memoirs of the Association of Australasian Palaeontologists. Member: GSA, AAP, PA and PS. John.Laurie@ga.gov.au |
Daniel Mantle is a research scientist in Geoscience Australia’s Petroleum and Marine Division. He holds a BSc (Hons) in Geology from Trinity College Dublin, Ireland (2001) and received a PhD on the Middle-Late Jurassic palynology of the Bonaparte Basin from the University of Queensland (2006). He worked for a year in the coal industry in Mongolia before returning to Australia in 2008 to commence work as the in-house palynologist at GA and to lead their Timescales and VCEMP unit. Member: PESA, GSA and AASP. Daniel.Mantle@ga.gov.au |
Robert (Bob) Nicoll was educated in the USA and obtained his PhD from the University of Iowa in 1971. He worked for the Bureau of Mineral Resources/ Australian Geological Survey Organisation for 28 years and is a school visitor in the Research School of Earth Sciences of the Australian National University, and is contracted to Geoscience Australia developing the Australian datapack for Time Scale Creator. His principal research interest involves all aspects of conodont biostratigraphy and palaeobiology from the Cambrian to the Triassic. Bob.Nicoll@ga.gov.au |
James (Jim) Ogg is a professor in Earth and Atmospheric Sciences at Purdue University in Indiana, USA, with research specialties ranging from Mesozoic ocean history and climate cycles to stratigraphic databases. Since completing his PhD at Scripps Institution of Oceanography, California (1981), he has served on 10 DSDP and ODP legs as palaeomagnetist, sedimentologist or logging scientist. As secretary-general of the International Commission on Stratigraphy (ICS, 2000–8), he was co-editor of A Geologic Time Scale 2004 and was lead author for the Concise Geologic Time Scale (2008). He is chair of the ICS Subcommission on Stratigraphic Information. His collaboration with Geoscience Australia on time scale databases and visualisation software began in 2007 during his sabbatical in Canberra. jogg@purdue.edu |
