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  • As part of the standard town capture and requirement for high-res imagery to assist with cadastral upgrade in the Wellington Shire, the opportunity was taken to survey Wellington (also Yeoval & Geurie) as a reasonably large catchment job to test the change to the processing methods using ellipsoid values rather than orthometric values.

  • Geoscience Australia is supporting the exploration and development of offshore oil and gas resources and establishment of Australia's national representative system of marine protected areas through provision of spatial information about the physical and biological character of the seabed. Central to this approach is prediction of Australia's seabed biodiversity from spatially continuous data of physical seabed properties. However, information for these properties is usually collected at sparsely-distributed discrete locations, particularly in the deep ocean. Thus, methods for generating spatially continuous information from point samples become essential tools. Such methods are, however, often data- or even variable- specific and it is difficult to select an appropriate method for any given dataset. Improving the accuracy of these physical data for biodiversity prediction, by searching for the most robust spatial interpolation methods to predict physical seabed properties, is essential to better inform resource management practises. In this regard, we conducted a simulation experiment to compare the performance of statistical and mathematical methods for spatial interpolation using samples of seabed mud content across the Australian margin. Five factors that affect the accuracy of spatial interpolation were considered: 1) region; 2) statistical method; 3) sample density; 4) searching neighbourhood; and 5) sample stratification by geomorphic provinces. Bathymetry, distance-to-coast and slope were used as secondary variables. In this study, we only report the results of the comparison of 14 methods (37 sub-methods) using samples of seabed mud content with five levels of sample density across the southwest Australian margin. The results of the simulation experiment can be applied to spatial data modelling of various physical parameters in different disciplines and have application to a variety of resource management applications for Australia's marine region.

  • Atmospheric monitoring of CO2 geological storage has developed from a concept to reality over less than a decade. Measurements of atmospheric composition and surface to air fluxes are now being made at onshore test sites, pilot projects, operational projects and likely future storage regions around the world. The motivation for atmospheric monitoring is usually to detect potential leakage from CO2 storage activities that might affect health and safety or to test the efficacy of carbon capture and storage (CCS) as a climate mitigation option. We have focused on the mitigation requirement, which involves determining whether potential leakage is below a maximum acceptable rate. Climatic considerations suggest that the maximum leakage rate of stored CO2 should be very small, of the order of 0.01% of that stored per year, globally averaged. Monitoring operational CO2 storage sites to confirm that potential leakage to the atmosphere is below this rate and to locate and quantify the any leakage flux can be a challenge, mainly because of the large and variable CO2 concentrations and fluxes in ecosystems and urban environments. We have developed and assessed atmospheric techniques during field experiments, during 4 years of monitoring the CO2CRC Otway Project, and by using model simulations. From this experience we are able to make recommendations about suitable technologies and strategies to optimise the capability of atmospheric monitoring of CCS in different environments. Abstract for paper to be presented at CO2CRC Research Symposium 2010, 1-3 December 2010, Melbourne

  • A newsletter to Project Stakeholders to inform of progress and future events

  • Seismic reflection and gravity potential field data acquired during the Geoscience Australia SW Margins Survey 2008-09 was used to investigate the distribution of volcanic facies and large-scale structural architecture of the Mentelle Basin, located on the southwestern margin of Australia. Based on structural differences the basin is subdivided into the Western (WMB) and Eastern (EMB) Mentelle Basins. Isopach and seismic facies maps were used to identify the thickness and distribution of volcanic facies. These maps show that volcanism is generally confined to the Western Mentelle Basin, with two distinct areas of thick volcanic deposits occurring in the central and northern portion. Two and three dimensional gravity forward models were used to investigate the structural architecture of the Mentelle Basin. Two dimensional gravity modelling shows that the crust is extremely thin in the WMB (c.10km), associated with two mantle highs. The crust thickens from the EMB (>20km) towards mainland Australia. The two modelled mantle highs coincide with the two seismically defined areas of thick volcanic deposits. Analogue models indicate that rift related volcanism is generally confined to the locus of extension where crustal thinning and strain are greatest. Thus results of gravity modelling and seismic interpretation have been interpreted to indicate that Jurassic - Cretaceous extension was focussed in the WMB. This thinning of the crust and presence of mantle highs suggests that the WMB is a failed rift formed during the initial breakup between Australia and Greater India and abandoned at the onset of spreading in the Perth Basin.

  • In plate boundary regions moderate to large earthquakes are often sufficiently frequent that robust estimates of fundamental seismic parameters such as the recurrence intervals of large earthquakes and maximum credible earthquake (Mmax) can be made. The same is not true for the Stable Continental Regions (SCRs) of the world. Large earthquakes are so infrequent that the data distributions upon which recurrence and Mmax estimates are based are heavily skewed towards magnitudes below Mw 5.0, and so require significant extrapolation up to magnitudes for which damaging ground-shaking might be expected. The rarity of validating evidence from palaeo-surface rupturing earthquakes limits the confidence with which extrapolated statistical parameters may be applied. Herein we present an earthquake catalogue containing, 150 palaeo-earthquakes, from 60 palaeo-earthquake features, based upon a >100 ka record of palaeo-earthquakes recorded in the Precambrian Shield of southwest Western Australia. From this data we show that Mmax for non-extended-SRC is well constrained at M7.22 and M7.65 for extended-SCR. In non-extended-SRC the earthquakes are likely episodic with periods of quiescence of 10-100ka in between active phases. The largest earthquakes are likely to occur on pre-existing faults. We expect these results might apply to most areas of non-extended-SCR worldwide.

  • The aim of this document is to * outline the general process adopted by Geoscience Australia in modelling storm surge inundation for projects conducted in collaboration with Australian and State Government planning agencies * allow discoverability of all data used to generate the products for the collaborative projects as well as internal activities

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  • Geoscience Australia is the national custodian for coastal geoscientific data and information. The organisation developed the OzCoasts web-based database and information system to draw together a diverse range of data and information on Australia's coasts and its estuaries. Previously known as OzEstuaries, the website was designed with input from over 100 scientists and resource managers from more than 50 organisations including government, universities and the National Estuaries Network. The former Coastal CRC and National Land and Water Resources Audit were instrumental in coordinating communication between the different agencies. Each month approximately 20,000 unique visitors from more than 140 countries visit the website to view around 80,000 pages. Maps, images, reports and data can be downloaded to assist with coastal science, monitoring and management. The content is arranged into six inter-linked modules: Search Data, Conceptual Models, Coastal Indicators, Habitat Mapping, Natural Resource Management, Landform and Stability Maps. More....

  • During 2008 and 2009, and under the Australian Government's Onshore Energy Security Initiative, Geoscience Australia acquired airborne electromagnetic (AEM) data over the Pine Creek Orogen of the Northern Territory. The survey area was split into three areas for acquisition. VTEM data was acquired in the Kombolgie area east of Kakadu National Park (this data set) between August and November 2008. TEMPEST data was acquired west of Kakadu National Park with the area split in two to facilitate the use of two aircraft: the Woolner Granite area in the north was acquired between October and December 2008; and the Rum Jungle area adjoining to the south, was acquired between October 2008 and May 2009. The main purpose of the surveys was to provide additional geophysical/geological context for unconformity style uranium mineral systems and thereby promote related exploration. The survey data will also provide information on depth to Proterozoic/Archean basement, which is of general interest to explorers, and will be used as an input into ground water studies in the region. This dataset includes the subscriber company data K1 K2 and K3.