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  • The tectonic origin, paleoearthquake histories and slip rates of six normal faults (referred to here as the Rahotu, Oaonui, Kina, Kiri, Ihaia and Pihama faults) have been examined for up to ~26 kyr within the Taranaki Rift, New Zealand. A minimum of 13 ground-surface rupturing paleoearthquakes have been recognised on four of the faults using analysis of displaced late Quaternary stratigraphy and landforms. These data, in combination with 21 new radiocarbon dates, constrain the timing, slip and magnitude of each earthquake. The faults have low throw rates (~0.1-0.8 mm/yr) and appear to be buried near the Mt Taranaki volcanic cone. Recurrence intervals between earthquakes on individual faults typically range from 3-10 kyr (average ~ 6 kyr), with slip/earthquake ranging from ~0.3-1.5 m (average ~0.7 m). Recurrence intervals and slip/earthquake typically vary by up to a factor of three on individual faults, with only the Oaonui Fault displaying near-characteristic slip (of about 0.5 m) during successive earthquakes. The timing and slip of earthquakes on individual faults appear to have been interdependent, with each event possibly relieving stress and decreasing the likelihood of additional earthquakes across the system. Earthquake magnitudes are estimated to be M 6.5-6.7. The dating resolution of paleoearthquakes is generally ±1-2 kyr and is presently too imprecise to test the temporal relations between seismic events and either volcanic eruptions or lahars formed by debris avalanches during cone collapse. It is unlikely, however, that formation of the ~7.8 kyr Opua Formation lahar was triggered by a large earthquake on the Rahotu, Oaonui or Kina faults which, of the faults studied, are farthest from the Mt Taranaki volcanic cone.

  • The tragic events of the Indian Ocean tsunami on 26 December 2004 highlighted shortcomings in the alert and response systems for tsunami threats to Western Australia's (WA) coastal communities. To improve community awareness and understanding of tsunami hazard and potential impact for Western Australia, the Fire and Emergency Services Authority of WA (FESA) established a collaborative partnership with GA in which science and emergency management expertise was applied to identified communities.

  • This map shows area of the West Coast Tasmania Shark Gillnet and Shark Hook Sector 130m Depth Commonwealth Closure. Modified from GeoCat 65105 (2007) as per the Southern and Eastern Scalefish and Shark Fishery (Closures) Direction No. 1 2009 - Schedule 14. Produced for the Australian Fisheries Management Authority. Not for public sale or distribution by GA.

  • Geoscience Australia has developed an interactive 3D viewer for three national datasets; the new Radiometric Map of Australia (Geoscience Australia 2009b), the Magnetic Anomaly Map of Australia (Geoscience Australia 2004), and the Gravity Anomaly Map of the Australian Region (Geoscience Australia 2008). The interactive virtual globe is based on NASA's open source World Wind Java Software Development Kit (SDK) and provides users with easy and rich access to these three national datasets. Users can view eight different representations of the radiometric map and compare these with the magnetic and gravity anomaly maps and satellite imagery; all draped over a digital elevation model. The full dataset for the three map sets is approximately 55GB (in ER Mapper format), while the compressed full resolution images used in the virtual globe total only 1.6GB and only the data for the geographic region being viewed is downloaded to users computers. This paper addresses the processes for selecting the World Wind application over other solutions, how the data was prepared for online delivery, the development of the 3D Viewer using the Java SDK, issues involving connecting to.

  • The aim of this document is to provide the Fire and Emergency Services Authority of Western Australia (FESA) with a preliminary assessment of tsunami risk to a number of communities in South West WA. This assessment follows the preliminary assessment of tsunami impact for six North West Shelf communities and probabilistic tsunami hazard assessment for Western Australia which described the chance of a given tsunami wave height at the 50m contour being exceeded.

  • This map shows the boundary of the security regulated port for the purpose of the Maritime Transport & Office Security Act 2003. 2 Sheets (Colour) 2 Sheets (B&W) August 2009 Not for sale or public distribution Contact Manager LOSAMBA project, PMD

  • The historical record reveals that at least five tsunamis have impacted the Western Australian coast (1993, 1977, 1994, 2004, 2006). We document the geomorphic effects of these tsunamis through field investigations, analysis of pre and post-tsunami satellite imagery, collation of historical reports and recording of eyewitness accounts. The tsunamis had flow depths of less than 3 m, inundation distances of up to several hundred metres and a maximum recorded run-up height of 8 m a.s.l. Geomorphic effects include off-shore and near-shore erosion and extensive vegetation damage. In some cases, vegetated foredunes were severely depleted or completely removed. Gullies and scour pockets up to 1.5 m deep were eroded into topographic highs during tsunami outflow. Eroded sediments were redeposited landward as sediment sheets several centimetres thick. Isolated coral blocks and oyster-encrusted boulders were deposited over coastal dunes. However, boulder ridges were often unaffected by tsunami flow. The extent of inundation from the most recent tsunamis can be distinguished as strandlines of coral rubble and rafted vegetation. It is likely taht these features are ephemeral and seasonal coastal processes will obscure all traces of these signatures within years to decades. Recently reported evidence for Holocene palaeotsunamis on the Western Australian coast suggests significantly larger run-up and inundation than observed in the historical record. The evidence includes signatures such as chevrons dunes that have not been observed to form during historical events. We have compared the geomorphic effects of historical tsunami with reported palaeotsunami evidence from Coral Bay, Cape Range Peninsula and Port Samson. We conclude that much of the postulated palaeotsunami evidence can be explained by more common and ongoing geomorphic processes such as reef evolution, aeolian dune development and archaeological site formation.

  • Exploration models for Rot Rock geothermal energy plays in Australia are based primarily on high-heat producing granites (HHPG) in combination with overlying low-conductivity sedimentary rocks providing the insulator necessary to accumulate elevated temperatures at unusually shallow (therefore accessible) depths. Unknowns in this style of geothermal play include the composition and geometry of the HHPG and thermal properties, and the thickness of the overlying sediments. A series of 3D geological models have been constructed to investigate the range of geometries and compositions that may give rise to prospective Hot Rock geothermal energy plays. A 3D geological map of the Cooper Basin region which contains known HHPG beneath thick sedimentary sequences, has been constructed from gravity inversions and constrained by geological data. The inversion models delineate regions of low density within the basement that are inferred to be granitic bodies. Thermal forward modelling was carried out by incorporating measured and estimated thermal properties to the mapped lithologies. An enhancement of the GeoModeller software is to allow the input thermal properties to be specified as distribution functions. Multiple thermal simulations using Monte-Carlo methods would be carried out from the supplied distributions. Statistical methods will be used to yield the probability estimates of the in-situ heat resource, reducing the risk of exploring for heat. The two thermal modelling techniques can be used as a predictive tool in regions where little or no temperature and geological data are available.

  • Map produced for the Australian Government Solicitor in March 2009 showing the Torres Strait Regional Claim (Q6040 of 2001) as mofidied and the Great Barrier Reef Marine Park. For confidental/internal use by AGS and not for general release.

  • This map shows the area of the Portland Area Trawl Closure within the Commonwealth Trawl Sector (also known as the Commonwealth South East Trawl Fishery (SETF)) of the Southern and Eastern Scalefish and Shark Fishery. Modified from GeoCat 68493 (2008) as per the Southern and Eastern Scalefish and Shark Fishery (Closures) Direction No. 1 2009 - Schedule 23. Produced for the Australian Fisheries Management Authority. Not for public sale or distribution by GA.