Petrophysics

Petrophysics is the study of the physical and chemical properties of rocks and their contained fluids.

Following a pilot project in 2020–21, the Geological Survey of Western Australia (GSWA) is embarking on a long-term strategic program of systematic petrophysical measurement of drillcore samples from significant mineral deposits, poorly explored regions, and reference stratigraphic drillholes. The long-term objective of this program is to acquire a broad suite of data to define the petrophysical characteristics of key lithostratigraphic units, alteration patterns or major mineral system environments. It is anticipated that 1000–2000 samples will be analysed annually.

GSWA
A sample of core in the Perth Core Library selected for petrophysical analysis

The program is funded through the Western Australian Government Exploration Incentive Scheme and will enable more informed decision making for the resources exploration industry, government agencies and solid Earth sciences research in Western Australia.

Currently, the properties acquired during petrophysical analysis are:

  • magnetic susceptibility
  • remanent magnetization
  • dry bulk density
  • apparent porosity
  • galvanic resistivity
  • induced polarization
  • inductive conductivity
  • P-wave sonic velocity
  • acoustic impedance
  • gamma ray.

Additional properties might be acquired in the future as the program evolves.

Current data and reports can be found in the MAGIX database:

Laboratory measurement process (courtesy Terra Petrophysics)
Laboratory measurement process (courtesy Terra Petrophysics)
Magnetic susceptibility vs dry bulk density example from the Paterson Orogen
Magnetic susceptibility vs dry bulk density example from the Paterson Orogen

Publications

Contact

For further information contact:
geophysics@dmirs.wa.gov.au