Hydrocarbon Gas Measurements in Otway and Gippsland Basin Sediments

Light hydrocarbon gas concentrations (C1-C6) were measured in sediment samples from 342 locations on the continental shelf and upper slope. The dataset results from a 21-day research cruise in April/May 1988 conducted by the BMR research vessel 'Rig Seismic'. It identifies 42 locations with evidence of thermogenic hydrocarbons in near-surface sediments.

Use Cases

• Identify potential hydrocarbon seepage zones by mapping the 42 locations with thermogenic gas signatures across the Otway and Gippsland Basins.
• Assess hydrocarbon source rock maturity and type by analyzing the spatial distribution of wet gas content ratios ([C2-C4/C1-C4] x 100).
• Correlate total C1-C4 gas concentrations with geological structures, such as comparing higher concentrations in the Voluta Trough to basin margins.
• Integrate geochemical data with thermal maturation models to evaluate the hydrocarbon potential of specific stratigraphic units like the Early Cretaceous Otway Group.

Strengths

• Measurements from 342 distinct sediment sample locations provide broad spatial coverage.
• Data identifies thermogenic hydrocarbons at 42 specific sites (32 in Otway, 10 in Gippsland).
• Research conducted over a focused 21-day cruise ensures consistent sampling methodology.

Limitations

• Data is from a single cruise in 1988, representing a snapshot in time with no temporal series.
• Sample size for confirmed thermogenic hydrocarbon sites is limited to 42 locations.
• Primary data formats are PDF and HTML reports, which may require extraction for quantitative analysis.

Provenance

Source

Australian Ocean Data Network, originating from the BMR Fossil Fuels Project.

Collection Method

Ship-based sampling and geochemical analysis of sediments during a dedicated research cruise.

Time Range

April/May 1988.

Freshness

null

Geography

Offshore Otway Basin (17 days) and Gippsland Basin (4 days), Australia.