Mid-Tertiary Permeability Barriers in the Murray Basin, Southeastern Australia

A paper summarizing the stratigraphy, distribution, and geometry of mid-Tertiary units forming subsurface permeability barriers in the Murray Basin. The analysis is based on subsurface facies analysis of borelogs and palaeogeographic reconstructions, indicating at least three separate marine incursions during the Cainozoic. The data originates from Geoscience Australia and was last updated in March 2026.

Use Cases

• Modeling groundwater flow disruption based on the described arcuate low-permeability barrier formed by the Winnambool Formation and Geera Clay.
• Analyzing aquifer geometry and confining layers based on the stratigraphic relationships between the Renmark Group, Ettrick Formation, and Murray Group.
• Estimating historical porosity changes based on the visual porosity analysis of the Geera Clay from the Piangil West-2 borehole core.
• Reconstructing palaeogeographic marine incursions based on the described three separate Cainozoic sea invasions of the basin.

Strengths

• Includes specific porosity estimates (0-7% effective, 5-10% original) from a fully cored borehole section.
• Provides detailed stratigraphic thicknesses (e.g., 10-30 m for Ettrick Formation, >100 m for Murray Group limestone).
• Contains a temporal framework for geological events, such as a marine incursion commencing about 32 million years ago.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Data is presented in PDF/HTML formats, which may require extraction for computational analysis.

Provenance

Source

Geoscience Australia Data

Collection Method

Subsurface facies analysis of borelogs and palaeogeographic reconstructions.

Time Range

Mid-Tertiary (Oligocene to Miocene), with events described from about 32 million years ago.

Freshness

Last updated 2026-03 25 18:11:27.240927; freshness should be verified.

Geography

Murray Basin, southeastern Australia.