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  • We present new paleoseismicity data for the 30 km long and 2.5 m high Hyden fault scarp in Western Australia, which, when combined with the results of previous research, provides the most extensive record of surface rupturing earthquakes yet assembled for an "active" Australian intracratonic fault. The data indicate that four to five surface rupturing earthquakes have occurred on the Hyden Fault during the Quaternary (E1: ca. 20 ka, E2: ca. 50-55 ka, E3: ca. 90-100 ka, and two events E4 and E5, >200 ka). Activity is episodic, with single seismic cycle slip rates varying from 0.03 mm/yr to less than 0.01 mm/yr. Palaeo-earthquake magnitudes are estimated to have been in the order of M 6.8. The identification of a similar fault scarp immediately northwest of the Hyden scarp, and of two air-photo lineaments to the west of the Hyden scarp, indicates that strain is distributed amongst a family of faults in this region. The presence of multiple nearby active faults suggests that the recurrence of severe ground shaking in the Hyden region is more frequent than indicated by the palaeoseismic data presented here.

  • Diagram produced for the Bureau of Meteorology showing the proposed positions of DART buoys witin the Tasman Sea. For internal use of BOM.

  • This data package is an archive of geospatially located and other digital data covering the southern Arunta region, a portion of the North Australia Project undertaken to understand elements within the North Australia Craton and its boundaries. It includes digital geospatical feature data and /or images for a number of 1:250 000 and 1:100 000 geological maps, mineral locations, geophysical images, company drill hole and rock chip data, geochemistry, and regional themes. It also includes publications and geospatial data relating to the mafic-ultramafic study module in the southern Arunta.

  • Preliminary results from the Thomson-Lachlan Deep Seismic Survey, northwest New South Wales

  • The 4-10 km-thick Bangemall Supergroup, comprising the Edmund and Collier groups, was deposited between 1620 Ma and 1070 Ma in response to intracratonic extensional reactivation of the Paleoproterozoic Capricorn compressional orogen. The supergroup can be further divided into six depositional packages bounded by unconformities or major marine flooding surfaces. Samples of each of the major sandstone units within these packages have been collected for detrital zircon provenance analysis. U-Pb dating of over 1200 detrital zircon grains has failed to identify any syndepositional magmatism, but provides an extensive dataset for evaluating the provenance history of the Bangemall Supergroup and implications for the Mesoproterozoic paleogeography of the West Australian Craton. Integration of this detrital zircon data with palaeocurrent data indicates that all source areas were located within the Mesoproterozoic West Australian Craton, with the main source area for the northern Bangemall Supergroup being the Gascoyne Complex and southern Pilbara Craton. All samples have prominent age modes in the 1850-1600 Ma range, indicating significant contribution from the northern Gascoyne Complex and coeval sedimentary basins. Some samples also display prominent modes in the 2780-2450 Ma range, consistent with derivation from the Fortescue and Hamersley groups. The provenance history of the Edmund Group records unroofing of the underlying basement, from the Gascoyne Complex to the Archean granites and greenstones of the Pilbara Craton. This results in detrital age-spectra in which the dominant modes become older upwards. In contrast, the Collier Group records unroofing of the underlying Edmund Group, and is characterized by age-spectra in which the dominant modes become younger upwards. These data imply that the West Australian Craton remained intact throughout the Mesoproterozoic assembly of Rodinia, and was the only source of detritus for the Bangemall Supergroup. Keywords: Bangemall Supergroup, Edmund Group, Collier Group, paleocurrents, provenance, zircon

  • Legacy product - no abstract available

  • Thomson-Lachlan Boundary Deep Seismic Reflection Survey Poster

  • The North Australia Project (NAP) was initiated in July 2000 following negotiations between the Northern Territory Geological Survey (NTGS) and the Australian Geological Survey Organisation (now Geoscience Australia). The NAP was a joint project undertaking geoscientific studies in the Tanami, Arunta and Tennant regions of central Australia to help encourage mineral exploration. The project continued until June 2004, when the Geological Survey of Western Australia (GSWA) began regional data acquisition in the western Tanami region. In July 2004, the Tanami Project, a joint initiative between Geoscience Australia, NTGS, and GSWA to increase mineral exploration replaced the NAP. Although NTGS and GSWA have continued interests in the Tanami and Arunta regions, the collaborative Tanami Project will finish in December 2006. The purpose of this product is to provide reports and datasets summarising the results of the project at this time. The only major products not included in this DVD are the results of the Tanami seismic survey and modifications to the on-line 3D models required by the seismic results. These will be released separately, beginning in August 2006. As this report is intended to be as up-to-date as possible, it refers to a number of manuscripts that are either in press or in preparation. Although these manuscripts cannot be provided here, much of the data upon which the conclusions are based are presented in summary, either in abstracts, presentations, or data tables.

  • A movie (~10 mins) showing the scientific discovery of the submerged reefs of the Gulf of Carpentaria. It describes the coral reef survival, growth and death; the change in sea level, global climate and ocean currents.