The critical success factors which control hydrocarbon prospectivity in the Otway Basin have been investigated using petroleum systems approaches. Greater than 99% of the hydrocarbon inventory within the Victorian Otway Basin has been sourced from Austral 2 (Albian-Aptian) source rocks and these accumulations are typically located either within, or within approximately 3,000 m of source rock kitchens which are at peak thermal maturity at present day. Importantly, the zones of greatest prospectivity are located where these source rocks have been actively generating and expelling hydrocarbons throughout the Late Tertiary, primarily as a result of sediment loading associated with progradation of the Heytesbury shelfal carbonates. This peak generation window occurs at an average depth of approximately 2,500-3,500 m 'sub-mud' across much of the basin, which has allowed prospective hydrocarbon fairways to be mapped out, thereby highlighting areas of greatest prospectivity. It is believed that the spatial proximity of the actively generating source rocks to the accumulations is due to several factors, which includes overall poor fault seal in the basin (success cases occur where charge rate exceeds leakage rate) and relatively complex and tortuous migration fairways (which means that large volumes of hydrocarbons are only focussed and migrate for relatively short distances). etc

Legacy product - no abstract available

Legacy product - no abstract available

February 2001 Bonaparte Basin - Gas Data The gas database contains molecular compositional and isotopic data for gases from the Bonaparte Basin as exported from AGSO's Orgchem database on 6th February 2001. The output represents those gases for which the data is considered not to be "commercial-in-confidence". Also included is a document which gives a description of the data fields. Copyright (C) Commonwealth of Australia, 2000.

Restricted on advice from A. Barrett

Natural gas is Australia's third largest energy resource after coal and uranium but despite this economic importance, the gas origin is not always recognized. To address this, isotope and geochemistry data have been collated on 850 natural gases from all of Australia's major gas provinces with proposed source ages spanning the earliest Paleozoic to the Cenozoic. Unaltered natural gases have a thermogenic origin ('13C methane ranges between -49 and -27'; 'D methane ranges between -290 and -125'). Microbially altered natural gases were identified primarily on the basis of 13C and D enrichments in propane and/or 13C depletion in methane and/or 13C enrichment in CO2. The carbon isotopic composition of the gas source has been estimated using '13C iso-butane as a surrogate for '13C kerogen while for gases where biodegradation is moderate to severe, '13C neo-pentane provides an alternative measure. The '13C kerogen of gas source rocks range from -47 to -22' with the older Paleozoic sources and marine kerogen amongst the most depleted in 13C. The '13C CO2 also provides an insight into crustal- and mantle-derived components while '15N N2 (-6.0 to 2.3' for N2 up to 47 %) distinguish between organic and inorganic (groundwater) inputs. This dataset provides a better understanding on the source and preservation history of Australian gas accumulations with direct implications on improving exploration success.

2002 and 2003 may well prove to be pivotal years for petroleum exploration in Australia as we endeavour to meet our twin imperatives of finding more oil and using gas. Long term gas supply contracts have been signed with China and a number of key oil discoveries have been made both on and offshore. Deep water wells will be drilled that have the potential to usher in another phase of major oil discovery akin to bonanza of the 1960s, when the first steps into the offshore resulted in billion barrel discoveries in Bass Strait. By the close of the first successful cycle of exploration in Australia (1960 to 1972) all currently producing basins were identified as petroliferous, the major play types had been established and over 60% of Australia?s current oil reserves found. The key drivers of this phase were the access to new basins opened up by the move to offshore exploration and the stimulus to further exploration provided by discovery success. The same drivers are apparent now. Recent discoveries in the Perth, Carnarvon, Otway and Browse basins provide strong indications that a significant new cycle of exploration success is already underway. In many cases these finds represent the largest fields yet found in the basin or at least the largest in the last thirty years. The usual discovery history trend of declining field sizes over time has been turned on its head - clearly demonstrating that many of Australia?s currently producing basins still have a long way to run and encouraging further exploration efforts. Perhaps of even more importance to Australia?s long term liquids self sufficiency is the current deepwater drilling campaign which is stepping out beyond former geographic limits. The first wells in major Mesozoic depocentres on the outer margin of the North west Shelf and in the Great Australian Bight are being drilled with the potential to establish entirely new petroleum provinces.

This Oil and Gas Resources of Australia 2008 publication is the successor to Oil and Gas Resources of Australia 2007 and continues as the definitive reference on exploration, development and production of Australia's petroleum resources. The tables describe: - wells drilled - seismic surveys - petroleum discoveries - petroleum reserves - production and development, including forecasts of crude oil and condensate from 2009 to 2025 and a listing of offshore facilities

The Roebuck Basin on Australia’s offshore north-western margin is the focus of a regional hydrocarbon prospectivity assessment being undertaken by the Offshore Energy Systems Section. This offshore program is designed to produce pre-competitive information to assist with the evaluation of the hydrocarbon resource potential of the central North West Shelf and attract exploration investment to Australia. As part of this program, molecular and isotopic analyses were undertaken by Geoscience Australia on gas samples from the well Dorado 1 and the raw data from these analyses are released in this report.

The Source Rock and Fluids Atlas delivery and publication services provide up-to-date information on petroleum (organic) geochemical and geological data from Geoscience Australia's Organic Geochemistry Database (ORGCHEM). The sample data provides the spatial distribution of petroleum source rocks and their derived fluids (natural gas and crude oil) from boreholes and field sites in onshore and offshore Australian basins. The services provide characterisation of source rocks through the visualisation of Pyrolysis, Organic Petrology (Maceral Groups, Maceral Reflectance) and Organoclast Maturity data. The services also provide molecular and isotopic characterisation of source rocks and petroleum through the visualisation of Bulk, Whole Oil GC, Gas, Compound-Specific Isotopic Analyses (CSIA) and Gas Chromatography-Mass Spectrometry (GCMS) data tables. Interpretation of these data enables the characterisation of petroleum source rocks and identification of their derived petroleum fluids that comprise two key elements of petroleum systems analysis. The composition of petroleum determines whether or not it can be an economic commodity and if other processes (e.g. CO2 removal and sequestration; cryogenic liquefaction of LNG) are required for development.