Product catalogue
Magnetotelluric data – mapping from the lithosphere to the near surface for mineral exploration
The footprint of a mineral system is potentially detectable at a range of scales and lithospheric depths, reflecting the size and distribution of its components. Magnetotellurics is one of a few techniques that can provide multiscale datasets to understand mineral systems. The Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) is a collaborative national survey that acquires long-period magnetotelluric data on a half-degree grid spacing (about 55 km) across Australia. This project aims to map the electrical conductivity/resistivity structure in the crust and mantle beneath the Australian continent. We have used AusLAMP as a first-order reconnaissance survey to resolve large-scale lithospheric architecture for mapping areas of mineral potential in Australia. AusLAMP results show a remarkable connection between conductive anomalies and giant mineral deposits in known highly endowed mineral provinces. Similar conductive features are mapped in greenfield areas where mineralisation has not been previously recognised. In these areas we can then undertake higher-resolution infill magnetotelluric surveys to refine the geometry of major structures, and to investigate if deep conductive structures are connected to the near surface by crustal-scale fluid-flow pathways.
This presentation summarises the results from a 3D resistivity model derived from AusLAMP data in Northern Australia (Figure 1). This model reveals a broad conductivity anomaly in the lower crust and upper mantle that extends beneath an undercover exploration frontier between the producing Tennant Creek region and the prospective Murphy Province to the northeast. This anomaly potentially represents a fertile source region for mineral systems. A subsequent higher-resolution infill magnetotelluric survey revealed two prominent conductors within the crust (Figure 2) whose combined responses produced the lithospheric-scale conductivity anomaly mapped in the AusLAMP model. Integration of the conductivity structure with deep seismic reflection data revealed a favourable crustal architecture linking the lower, fertile source regions with potential depositional sites in the upper crust. Integration with other geophysical and geochronological datasets suggests high prospectivity for major mineral deposits in the vicinity of major faults.
In addition to these insights, interpretation of high-frequency magnetotelluric data helps to characterise cover and assist with selecting targets for stratigraphic drilling.
This study demonstrates that the integration of geophysical data from multiscale surveys is an effective approach to scale reduction during mineral exploration in covered terranes. The success of this data integration and scale reduction approach is demonstrated by the uptake of over 11,000 square kilometres of new exploration tenements in the previously under-explored East Tennant region of northern Australia.
This abstract was submitted to and presented at the 26th World Mining Congress (WMC) 2023 ( https://wmc2023.org/)
Simple
Identification info
- Date (Creation)
- 2023-05-01
- Date (Publication)
- 2023-10-30T01:33:57
- Citation identifier
- Geoscience Australia Persistent Identifier/https://pid.geoscience.gov.au/dataset/ga/146485
Identifier
- Codespace
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Digital Obejct Identifier
- Cited responsible party
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Role Organisation / Individual Name Details Publisher Commonwealth of Australia (Geoscience Australia)
Voice Point of contact Jiang, W.
MEG Internal Contact Resource provider Minerals, Energy and Groundwater Division
External Contact
- Name
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26th World Mining Congress (WMC) 26-29 June 2021, Brisbane, Australia
- Purpose
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presentation to WMC2023
- Status
- Completed
- Point of contact
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Role Organisation / Individual Name Details Point of contact Commonwealth of Australia (Geoscience Australia)
Voice Point of contact Jiang, W.
MEG Internal Contact Resource provider Minerals, Energy and Groundwater Division
External Contact
- Spatial representation type
- Topic category
-
- Geoscientific information
Extent
))
- Maintenance and update frequency
- As needed
Resource format
- Title
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Product data repository: Various Formats
- Website
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Data Store directory containing the digital product files
Data Store directory containing one or more files, possibly in a variety of formats, accessible to Geoscience Australia staff only for internal purposes
- theme.ANZRC Fields of Research.rdf
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EARTH SCIENCES
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- Theme
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magnetotelluric
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- Theme
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mineral exploration
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- Keywords
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geophysical data
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- Keywords
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multiscale surveys
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- Keywords
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Published_External
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Resource constraints
- Title
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Creative Commons Attribution 4.0 International Licence
- Alternate title
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CC-BY
- Edition
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4.0
- Access constraints
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- License
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(c) Commonwealth of Australia (Geoscience Australia) 2023
Resource constraints
- Title
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Australian Government Security ClassificationSystem
- Edition date
- 2018-11-01T00:00:00
- Classification
- Unclassified
- Language
- English
- Character encoding
- UTF8
Distribution Information
- Distributor contact
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Role Organisation / Individual Name Details Distributor Commonwealth of Australia (Geoscience Australia)
Voice facsimile
- OnLine resource
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Link to Conference Page
Link to Conference Page
- Distribution format
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- OnLine resource
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Link to Abstract and Presentation
Link to Abstract and Presentation
- Distribution format
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Resource lineage
- Statement
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an abstract that will clearly convey the success of GA’s multiscale geophysical data acquisition and interpretation in reducing the search space in undercover frontiers
Metadata constraints
- Title
-
Australian Government Security Classification System
- Edition date
- 2018-11-01T00:00:00
- Classification
- Unclassified
Metadata
- Metadata identifier
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urn:uuid/dcadf339-f305-4146-ad24-fe5b6872a19d
- Title
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GeoNetwork UUID
- Language
- English
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- UTF8
- Contact
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Role Organisation / Individual Name Details Point of contact Commonwealth of Australia (Geoscience Australia)
Voice Owner Jiang, W
Geoscience Australia Internal Contact Point of contact Jiang, W.
MEG Internal Contact
Type of resource
- Resource scope
- Document
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Conference Abstracts
Alternative metadata reference
- Title
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Geoscience Australia - short identifier for metadata record with
uuid
- Citation identifier
- eCatId/146485
- Date info (Creation)
- 2020-09-02T06:12:14
- Date info (Revision)
- 2020-09-02T06:12:14
Metadata standard
- Title
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AU/NZS ISO 19115-1:2014
Metadata standard
- Title
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ISO 19115-1:2014
Metadata standard
- Title
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ISO 19115-3
- Title
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Geoscience Australia Community Metadata Profile of ISO 19115-1:2014
- Edition
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Version 2.0, September 2018
- Citation identifier
- https://pid.geoscience.gov.au/dataset/ga/144285