Evolution of the Lord Howe Rise basin systems and underlying basement terrances were influenced by multiple periods of tectonism and volcanic activity spanning the Palaeozoic to Tertiary. The prospects for hydrocarbon accumulations are moderate to high in several basins of the LHR, with evidence such as amplitude anamalies, bottom-simulating reflectors and low-level seeps observed on seismic and remotedly sensed data. The economic viability of exploration and production in this rremote region has not been assessed.

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A comprehensive black and white teachers' guide reviews the history and development of the United Nation's Convention on the Law of the Sea and its application to Australian marine jurisdiction. Case studies on the North West Shelf, Antarctica and Orange Roughy are included. 108 page booklet with student activities and suggested answers. Suitable for secondary geography and science students Years 8-12.

Sandstone deposits are important sources of uranium, accounting for approximately 20 percent of global production, largely through in situ leach (ISL) mining. Most of this production has come from deposits in the western US, Niger and Kazakhstan. In Australia, sandstone-hosted uranium is being produced from the Beverley deposit in the Frome Embayment of South Australia, and a second ISL mine is under development at Honeymoon in the same region. Such deposits form where uranium-bearing oxidised ground waters moving through sandstone aquifers react with reducing materials. The locations of ore zones and the sizes of mineral deposits depend, amongst other factors, on the abundance and the reactive nature of the reductant. Hence the nature and abundance of organic material in the ore-bearing sedimentary sequence may be of critical importance in the formation of sandstone uranium deposits. In sandstones rich in organic material (containing debris of fossil plants or layers of authigenic organic material) the organic materials either reduce uranium directly with bacteria as a catalyst, or result in production of biogenic H2S. In sandstones relatively poor in organic material, that the reduction can be caused either by the introduction of hydrocarbons and/or H2S from oil/gas fields within underlying sediments; or by H2S produced from the interaction of oxidised ground water with pyrite in the sandstone aquifer. This paper outlines the geology of the world-class sandstone uranium deposits in the Chu-Sarysu and Syr-Darya Basins in the south-central portion of Kazakhstan, which are hosted by sandstones relatively poor in organic matter. It highlights the crucial role of that hydrocarbons appear to have played in the formation of these and other large sandstone type uranium deposits. Based on the model developed, it is concluded that there is considerable potential in Australia for discovery of large sandstone hosted uranium mineralisation, including in little explored regions underlain by basins with known or potential hydrocarbons.

"An audit of petroleum exploration wells in the Bass Basin, 1966-1999" provides reasons for the success and failure of previous exploration drilling in the Bass Basin. It highlights the risks and uncertainties of exploration drilling and offers insights into prospectivity for future exploration. The CD-ROM provides information on structure, petroleum systems elements, maturity, hydrocarbon shows, and an assessment of the validity of each of the 32 wells in the Bass Basin. It also contains images of seismic ties and composite logs for each well.

The spectral signature of an about 1 micrometer thick oil slick has been identified from airborne hyperspectral data (HyMap sensor) acquired over a floating oil production facility located on the North West Shelf of Australia. The paper describes spectral characteristrics of the signature and identifies conditions in which it can be observed.

Petroleum accumulations have been discovered in the Bonaparte, Browse and Carnarvon basins over the last fifty years. However, a regional synthesis of the geochemistry of these North West Shelf hydrocarbons has not been published. To address this, this study documents the biomarker and isotopic analyses of ~300 North West Shelf oils/condensate samples that have been statistically characterised into genetically related families. Carbon and hydrogen isotopic signatures of ~50 gas samples, together with existing molecular data for ~1000 gas samples, show regional trends in wetness and abundance of non-combustible gases. These petroleum accumulations can be attributed to source rocks of Early Carboniferous, Permian, Triassic, Jurassic and Early Cretaceous age; however, most economic oil and gas accumulations are sourced from Mesozoic (Triassic Jurassic) sediments. The oils produced from the Bonaparte (Vulcan Sub-basin, northern Bonaparte) and Carnarvon (Dampier, Barrow and Exmouth sub-basins) basins are geochemically similar, being sourced from Late Jurassic marine rift-fill sediments (lower Vulcan Formation/Dingo Claystone) that contain variable amounts of terrigenous (particularly gymnosperm-derived) organic matter. Variations in their biomarker signatures can be explained by maturity differences, multiple charging and secondary alteration processes. Gas produced from the northern Rankin Platform is predominantly sourced from Triassic Jurassic fluvio-deltaic sediments. Proven and potential supergiant and giant gas accumulations occur in the deepwater areas of the North West Shelf. Case studies focussing on the geochemistry of the outer Browse (Scott Reef trend) and Carnarvon (deepwater Exmouth Plateau and Rankin Platform) gas accumulations will be presented with emphasis on d13C and d2H isotopic data.

Within the Central Australian region, nominally constrained by 22.5oS 134oE and 31.5oS 144oE for this study, lie several systems of stacked basins beneath the extensive Mesozoic Eromanga Basin. Remnants of Proterozoic basins are largely inferred from gravity, unexplored, and are not everywhere differentiated from an extensive cover of the lower Palaeozoic Warburton Formation. This sequence is the central link between the contiguous Amadeus, Officer and Georgina Basins, and the Thomson Fold Belt. Since the Carboniferous, the region has largely experienced intracratonic sag and has accumulated continental sediments, including thick coal measures, with intermittent tectonism and uplift. In late Early Cretaceous, marine conditions briefly invaded this subsiding region, but continental sedimentation resumed in the Late Cretaceous. Tectonism occurred in the Tertiary with basin inversion and subsequent formation of the Great Artesian Basin. In the Cainozoic, the region is again in subsidence and accommodating fluvial and aeolian sediment slowly into the Eyre Basin. The preserved depocentres of the Carboniferous-Permian-Triassic Cooper, Pedirka-Simpson, and Galilee Basins are spatially separate, although all contain comparable, largely organically-mature continental coal measure sequences.

Methane is present in all coals, but a number of geological factors influence the potential economic concentration of gas. The key factors are (1) depositional environment, (2) tectonic and structural setting, (3) rank and gas generation, (4) gas content, (5) permeability, and (6) hydrogeology. Commercial coal seam gas production in Queensland has been entirely from the Permian coals of the Bowen Basin, but the Jurassic coals of the Surat and Clarence-Moreton basins are poised to deliver commercial gas volumes. Depositional environments range from fluvial to delta plain to paralic and marginal marine coals in the Bowen Basin are laterally more continuous than those in the Surat and Clarence-Moreton basins. The tectonic and structural settings are important as they control the coal characteristics both in terms of deposition and burial history. The important coal seam gas seams were deposited in a foreland setting in the Bowen Basin and an intracratonic setting in the Surat and Clarence-Moreton basins. Both of these settings resulted in widespread coal deposition. The complex burial history of the Bowen Basin has resulted in a wide range of coal ranks and properties. Rank in the Bowen Basin coal seam gas fields varies from vitrinite reflectane of 0.55% to >1.1% Rv and from Rv 0.35-0.6% in the Surat and Clarence-Moreton basins in Queensland. High vitrinite coals provide optimal gas generation and cleat formation. The commercial gas fields and the prospective ones contain coals with >60% vitrinite. Gas generation in the Queensland basins is complex with isotopic studies indicating that biogenic gas, thermogenic gas and mixed gases are present. Biogenic processes occur at depths of up to a kilometre. Gas content is important, but lower gas contents can be economic if deliverability is good. Free gas is also present. Drilling and production techniques play an important role in making lower gas content coals viable. Since the Bowen and Surat basins are in a compressive regime, permeability becomes a defining parameter. Areas where the compression is offset by tensional forces provide the best chances for commercial coal seam gas production. Tensional setting such as anticline or structural hinges are important plays. Hydrodynamics control the production rate though water quality varies between the fields.

Seismic acquisition for the joint BMR-Woodside Petroleum program in the Dampier Sub-basin started at 0800 am on October 24, 1990 and was completed at 1150 am on Sunday October 28, 1990. A total of 352 km of high resolution seismic data was collected along the 17 agreed survey lines, of which 336 km were full stack data with a total 390 magnetic tapes being used. Data quality appears to be good. In addition to the seismic, a total of 530.6 km of water column geochemical data were also collected.