Geochemical Comparisons of Southern Australian Asphaltites and Cretaceous Source Rocks

Geochemical and carbon isotopic evidence links asphaltites from the southern Australian margin to mid-Cretaceous source rocks. The analysis includes comparisons with the Albian-Cenomanian Blue Whale Supersequence and the Albian Toolebuc Formation, focusing on biomarkers like C30 methylsteranes and metalloporphyrins. This dataset was prepared for the Eastern Australian Basins Symposium in 2001 and is provided by Geoscience Australia.

Use Cases

• Correlating hydrocarbon seeps to potential source rock units based on biomarker signatures described.
• Modeling paleo-depositional environments (e.g., anoxic deep water vs. shallow marine) using metalloporphyrin and isotopic evidence.
• Refining source rock age and location models for the Great Australian Bight based on geochemical comparisons.

Strengths

• Analysis includes diverse geochemical signatures such as carbon isotopes, C30 methylsteranes, C26 norsteranes, and metalloporphyrins.
• Compares samples from multiple geological formations and basins (Bight Basin, Eromanga Basin).
• Includes supporting evidence from artificial pyrolysis of polar fractions.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• The description contains apparent typographical errors (e.g., 'sonrce', 'ten?estrial', 'snpported').

Provenance

Source

Geoscience Australia Data

Collection Method

Geochemical and isotopic laboratory analysis of rock and asphaltite samples.

Time Range

Early to mid-Cretaceous (Albian-Cenomanian), with a possible Late Cretaceous component.

Freshness

Last updated 2026-04-20 03:21:13.510944; freshness should be verified.

Geography

Southern Australian margin, Bight Basin, Eromanga Basin