Surprisingly few natural hydrocarbon seeps have been identified in Australia's offshore basins despite studies spanning thirty years. Initial studies of natural hydrocarbon seepage around the Australian margin were generally based around the geochemical analysis of stranded bitumens, water column geochemical `sniffer' sampling, synthetic aperture radar or airborne laser fluorsensor. Later studies involved the integration of these remote sensing and geochemical techniques with mutli-channel and shallow seismic. A review of these earlier studies indicates that many seepage interpretations need to be re-evaluated and that previous data sets, when set in a global context, often represent normal background hydrocarbon levels. Relatively few sites of proven natural hydrocarbon seepage in Australia's offshore sedimentary basins can be reconciled with the dominantly passive margin setting and low recent sedimentation rates, which are not favourable for high rates of seepage, and difficulties in proving seepage on high energy, shallow carbonate shelves, where seabed features may be rapidly reworked and modern marine signatures are overprinted on authigenic seep carbonates. Active thermogenic methane seepage on the Yampi Shelf, the only proven documented occurrence in Australia, is driven by deposition of a thick Late Tertiary carbonate succession and Late Miocene tectonic reactivation. Therefore, to increase the success of detecting and correctly interpreting natural hydrocarbon seepage, data need to be analysed and integrated within the context of the local geological setting, and with an understanding of what is observed globally.

Magnetic field interpretation is not an alternative to palaeomagnetic methods of recovering remanent magnetization information, both because it deals with the resultant of induced and remanent magnetizations and because confidence in recovered magnetization directions cannot match than provided by direct palaeomagnetic measurement. Nevertheless, magnetic field interpretation is highly complementary to palaeomagnetic studies. Palaeomagnetism provides detailed information from small, localised samples whereas magnetic field interpretation provides estimates of the bulk magnetization of substantial volumes (which may be completely buried and un-sampled by boreholes). Without palaeomagnetic and rock magnetic studies much of the geological information latent in magnetic field measurements cannot be accessed, and without the coverage of magnetic field data the extents and relationships of subsurface magnetization events revealed by palaeomagnetic studies cannot be fully mapped.

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Subset of Rockchem whole-rock database release 3. Contains 1009 whole-rock analyses of rocks from the Arunta Block.

34th International Geological Congress (IGC) AUSTRALIA 2012 Brisbane, Australia 2 - 10 August 2012 COPY FOR AusIMM Bulletin December 2009 The 34th International Geological Congress (IGC), or AUSTRALIA 2012, will be held at the Brisbane Convention and Exhibition Centre (BCEC), from 2-10 August 2012. The IGC is generally held every four years and has a proud 140 year tradition. Recent IGCs have attracted 5,000-7,000 delegates, many more than attended the Sydney IGC in 1976. The scientific sponsor of the IGC is the International Union of Geological Sciences (IUGS: www.iugs.org).

Legacy product - no abstract available

Legacy product - no abstract available

Documentation describing the ROCKCHEM version 1 release of the Alkaline Rocks of Australia subset. Also describes the structure of the Oracle database.

Legacy product - no abstract available

Legacy product - no abstract available