Solutions

Mineral Resources Electromagnetics and Seismic Team – Solutions
Field Problem Typical question Scale Methods Contact Notes
Target detection All Will a geophysical prospecting system detect targets that I am interested in? What method(s) can I use to detect targets that I am interested in? Local to regional Electromagnetics, d.c. resistivity, induced polarisation, potential fields, seismics, nuclear magnetic resonance (NMR) Annetts, Davis, King
  1. A related question is survey design
Ground water Water content What percentage of water is contained? Local, to about 150 m NMR Davis, Cahill
  1. Regional-scale surveys are conducted by contractors. CSIRO is responsible for survey design, data QA/QC and interpretation
  2. Local surveys can be conducted in-house using a variety of methods tailored to particular targets
  3. Down hole surveying can be carried out in pre-existing drill holes with diameters greater than 43 mm
Aquifer dimensions What are the aquifer’s dimensions – what is its capacity? How deep is it? How continuous is it? Regional to prospect, to about 500 m depth Electromagnetics, downhole spectral gamma Davis, Cahill, Annetts
Quality What can I use the groundwater for? Is it potable? Has sea water intruded inland? If so, how far? Regional to prospect, to about 500 m depth NMR, electromagnetics Davis, Cahill
Mineral exploration Regolith characterisation How thick is the regolith? Does it contain mineralised zones? What about palaeochannels? Can these be mapped? Regional to prospect, to about 500 m depth Electromagnetics, d.c. resistivity, induced polarisation, potential fields, seismics Davis, Annetts, King
  1. Regional-scale surveys are conducted by contractors. CSIRO is responsible for survey design, data QA/QC and interpretation
  2. Local surveys can be conducted in-house using a variety of methods tailored to particular targets
Target characterisation Can a target’s presence be confirmed? Can its disposition be determined? Prospect, to about 1 km depth Electromagnetics, d.c. resistivity, induced polarisation, potential fields, seismics Davis, Cahill, Annetts
Basement characterisation How deep is the basement? What is its character? Regional to prospect Electromagnetics, potential fields Davis
Geotechnical Storage facility characterisation Is my storage facility leaking? From where and at what rate? Local Electromagnetics, d.c. resistivity, induced polarisation, potential fields, seismics King, Davis, Cahill, Annetts
  1. Time-lapse surveys required to establish rate and direction of any movement
  2. A variety of methods are employed depending on the storage facility

General notes

  1. Often, multiple geophysical methods are applied when addressing a problem. Members of geophysics-related teams must be involved in early stages of project planning in order to determine an optimal survey program to meet the project’s goals. CMR owns a large range of equipment and can collect data to support projects.
  2. Generally high resolution implies a shallow depth of investigation. Deep targets are often poorly resolved.
  3. Geophysical data generally require processing and interpretation in order to educe the geology from the geophysical measurements. Processing, because of the generally non-linear relationship between measurements and physical properties, can require significant time to deliver high-quality results.
  4. Members of geophysics-related teams must be involved in early stages of project planning in order to identify critical issues such as noise sources which can significantly reduce data quality