Australia-wide 3D Density and Magnetic Susceptibility Models: Method and Model Release

Two coincident, crustal-scale models, one of magnetic susceptibility and one of density, have been produced for a volume covering the Australian continent and extending down to 55.5 km depth. These models were produced using the UBC GIF MAG3D and GRAV3D inversion programs, respectively.


The inversions were constrained with geological reference models with layers for sediments, undifferentiated crust and the mantle. The reference model for the magnetic inversion incorporated a Curie depth surface below which magnetic susceptibility was set to zero.


Due to the size of the inversion problem to be solved, the volume was divided into 235 overlapping inversions, which were inverted separately and then recombined. The method of recombining the inversions relies on a cosine function to determine the weight of each property and then takes a weighted average. This method successfully attenuated the edge effects that would otherwise occur between models and allows them to be viewed as one seamless model that covers the whole of Australia.


Regions of coincident high-density (&gt;2.83 g/cm<sup>3</sup>) and high-magnetic susceptibility (&gt;0.0125 SI) within the top 10 km of the undifferentiated crust (termed magnetite proxies) are suggested to be related to ultramafic rocks and the magnetite-forming hydrothermal alteration stages of potentially fertile IOCG systems (see download link: Magnetite region grids) .


<b>Download Link & Description</b>

<b>•</b> GA Record (.pdf) - The report describing the method and model results. PDF document.

<b>•</b> Intermediate grids (.ers) - The Australia-wide intermediate grids of elevation, gravity, and total magnetic intensity. ERMapper (.ers) format.

<b>•</b> Magnetite region grids (.ers, .tif) - The Australia-wide magnetite proxy regions projected onto a 2D surface. ERMapper (.ers) and GeoTiff (.tif) format.

<b>•</b> Subset_[1-17] (.sg, .den, .sus) - The Australia-wide 3D density and magnetic susceptibility models in SGrid (.sg) and UBC-GIF (.den, .sus) formats. Also includes the geological reference model surfaces (.ts).

<b>•</b> Individual inversion files - GRAV3D and MAG3D input and output files for the 235 individual UBC-GIF inversions (before being recombined using cosine weighting).


<b>Individual inversion input/output files for A1-V2 are available on request from clientservices@ga.gov.au - Quote eCat# 149226</b> clientservices@ga.gov <b>Individual inversion input/output files for A1-V2 are available on request from clientservices@ga.gov.au - Quote eCat# 149226</b>


Due to their size, the Australia-wide models have been divided into subsets (labelled 1-17) for download.

Please refer to the image for the extent of the subsets.

Simple

Identification info

Date (Creation)
2024-03-06T12:00:00
Date (Publication)
2024-10-10T03:09:11
Citation identifier
Geoscience Australia Persistent Identifier/https://pid.geoscience.gov.au/dataset/ga/149226

Citation identifier
Digital Object Identifier/https://dx.doi.org/10.26186/149226

Cited responsible party
Role Organisation / Individual Name Details
Publisher

Commonwealth of Australia (Geoscience Australia)

 Voice
Author

Goodwin, J.

 Internal Contact
Name

GA Record

Issue identification

2024/54

Purpose

This GA Record documents the method for how the first seamless, crustal-scale, Australia-wide models of density and magnetic susceptibility were produced. It is combined with a release of the models and their supporting data.

Status
Completed
Point of contact
Role Organisation / Individual Name Details
Resource provider

Minerals, Energy and Groundwater Division

 External Contact
Point of contact

Commonwealth of Australia (Geoscience Australia)

 Voice
Point of contact

Goodwin, J.

 Internal Contact
Spatial representation type
Topic category
  • Geoscientific information

Extent

N
S
E
W


Maintenance and update frequency
As needed

Resource format

Title

Product data repository: Various Formats

Protocol

FILE:DATA-DIRECTORY

Name of the resource

Data Store directory containing the digital product files

Description

Data Store directory containing one or more files, possibly in a variety of formats, accessible to Geoscience Australia staff only for internal purposes

Project

  • Geophysical Acquisition and Processing Section

  • Australian Resources Framework

  • EFTF – Exploring for the Future

Keywords

  • Total Magnetic Intensity (TMI)

Keywords

  • gravity

Keywords

  • Magnetic Susceptibility

Keywords

  • density

Keywords

  • geophysical inversion

Keywords

  • UBC-GIF

Keywords

  • MAG3D

Keywords

  • GRAV3D

Keywords

  • full-crustal

Keywords

  • 3D model

theme.ANZRC Fields of Research.rdf

  • Magnetism and Palaeomagnetism

  • Gravimetrics

Keywords

  • Published_External

Resource constraints

Title

Creative Commons Attribution 4.0 International Licence

Alternate title

CC-BY

Edition

4.0

Website

https://creativecommons.org/licenses/by/4.0/

Addressee
Role Organisation / Individual Name Details
User

Any
Use constraints
License
Use constraints
Other restrictions
Other constraints

© Commonwealth of Australia (Geoscience Australia) 2024

Resource constraints

Title

Australian Government Security Classification System

Edition date
2018-11-01T00:00:00
Website

https://www.protectivesecurity.gov.au/Pages/default.aspx

Classification
Unclassified
Classification system

Australian Government Security Classification System

Associated resource

Association Type
Operated on by
Title

Magnetite Proxy Regions WMS

Citation identifier
150191

Citation identifier
063a64ab-402c-4d6b-9e73-e44bccf3c1a2

Website

http://pid.geoscience.gov.au/service/ga/150191

Link to eCat metadata record landing page

Associated resource

Association Type
Operated on by
Title

Magnetite Proxy Regions WCS

Citation identifier
150192

Citation identifier
a0973704-e1b7-416e-8092-272250928b4d

Website

http://pid.geoscience.gov.au/service/ga/150192

Link to eCat metadata record landing page

Associated resource

Association Type
Operated on by
Title

Magnetite Proxy Regions WMTS

Citation identifier
150193

Citation identifier
dfa20d39-9076-4ba0-8f4a-2f766d9719ac

Website

http://pid.geoscience.gov.au/service/ga/150193

Link to eCat metadata record landing page

Language
English
Character encoding
UTF8

Distribution Information

Distributor contact
Role Organisation / Individual Name Details
Distributor

Commonwealth of Australia (Geoscience Australia)

 Voice facsimile
OnLine resource

Download Record (pdf) [12.5 MB]

Download Record (pdf) [12.5 MB]

Distribution format

  • pdf

    File decompression technique

    nil

OnLine resource

Download Intermediate grids (.ers) [169.5 MB]

Download Intermediate grids (.ers) [169.5 MB]

Distribution format

  • sus den msh

    File decompression technique

    unzip

OnLine resource

Download Magnetite region grids (.ers, .tif) [6.4 MB]

Download Magnetite region grids (.ers, .tif) [6.4 MB]

Distribution format

  • sus den msh

    File decompression technique

    unzip

OnLine resource

Download subset 1 (zip) [344.8 MB]

Download subset 1 (zip) [344.8 MB]

Distribution format

  • sus den msh

    File decompression technique

    unzip

OnLine resource

Download subset 2 (zip) [285.7 MB]

Download subset 2 (zip) [285.7 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 3 (zip) [272.3 MB]

Download subset 3 (zip) [272.3 MB]

Distribution format

  • dens sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 4 (zip) [324.8 MB]

Download subset 4 (zip) [324.8 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 5 (zip) [290.8 MB]

Download subset 5 (zip) [290.8 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 6 (zip) [205.7 MB]

Download subset 6 (zip) [205.7 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 7 (zip) [322.2 MB]

Download subset 7 (zip) [322.2 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 8 (zip) [330.5 MB]

Download subset 8 (zip) [330.5 MB]

Distribution format

  • zip

    File decompression technique

    unzip

OnLine resource

Download subset 9 (zip) [233.3 MB]

Download subset 9 (zip) [233.3 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 10 (zip) [293.0 MB]

Download subset 10 (zip) [293.0 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 11 (zip) [298.3 MB]

Download subset 11 (zip) [298.3 MB]

Distribution format

  • sus den msh

    File decompression technique

    unzip

OnLine resource

Download subset 12 (zip) [318.8 MB]

Download subset 12 (zip) [318.8 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 13 (zip) [194.4 MB]

Download subset 13 (zip) [194.4 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 14 (zip) [218.1 MB]

Download subset 14 (zip) [218.1 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 15 (zip) [321.5 MB]

Download subset 15 (zip) [321.5 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 16 (zip) [239.2 MB]

Download subset 16 (zip) [239.2 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Download subset 17 (zip) [91.0 MB]

Download subset 17 (zip) [91.0 MB]

Distribution format

  • den sus msh

    File decompression technique

    unzip

OnLine resource

Magnetite Proxy Regions WMS

Magnetite Proxy Regions WMS

Distribution format

  • OGC:WMS

OnLine resource

Magnetite Proxy Regions WCS

Magnetite Proxy Regions WCS

Distribution format

  • OGC:WCS

OnLine resource

Magnetite Proxy Regions WMTS

Magnetite Proxy Regions WMTS

Distribution format

  • OGC:WMTS

Resource lineage

Statement

<div>Produced by the Geophysical Acquisition and Processing Section. A continuation of work presented by Goodwin and Lane (2021) on the North Australian Craton (NAC) 3D density and magnetic susceptibility models.</div>

<div>Version 1.1 Updates (13/01/2025): <br>

• Fixed an issue in the recombined density models where values increased towards the edges of the model. <br>

• Included an SGrid format for the density and magnetic susceptibility models (see subsets 1-17). <br>

</div>

Metadata constraints

Title

Australian Government Security Classification System

Edition date
2018-11-01T00:00:00
Website

https://www.protectivesecurity.gov.au/Pages/default.aspx

Classification
Unclassified

Metadata

Metadata identifier
urn:uuid/2a3a73e2-2eef-4cb3-a1dd-f8aff447038b

Title

GeoNetwork UUID

Language
English
Character encoding
UTF8
Contact
Role Organisation / Individual Name Details
Point of contact

Commonwealth of Australia (Geoscience Australia)

 Voice
Point of contact

Goodwin, J.

 Internal Contact

Type of resource

Resource scope
Document
Name

GA Record

Alternative metadata reference

Title

Geoscience Australia - short identifier for metadata record with uuid

Citation identifier
eCatId/149226

Metadata linkage

https://ecat.ga.gov.au/geonetwork/srv/eng/catalog.search#/metadata/2a3a73e2-2eef-4cb3-a1dd-f8aff447038b

Metadata linkage

https://ecat.ga.gov.au/geonetwork/api/eng/catalog.search#/metadata/2a3a73e2-2eef-4cb3-a1dd-f8aff447038b

Metadata linkage

https://ecat.ga.gov.au/geonetwork/ofmJ3/eng/catalog.search#/metadata/2a3a73e2-2eef-4cb3-a1dd-f8aff447038b

Metadata linkage

https://ecat.ga.gov.au/geonetwork/dashboard/eng/catalog.search#/metadata/2a3a73e2-2eef-4cb3-a1dd-f8aff447038b

Metadata linkage

https://ecat.ga.gov.au/geonetwork/static9008124/eng/catalog.search#/metadata/2a3a73e2-2eef-4cb3-a1dd-f8aff447038b

Metadata linkage

https://ecat.ga.gov.au/geonetwork/static/eng/catalog.search#/metadata/2a3a73e2-2eef-4cb3-a1dd-f8aff447038b

Date info (Creation)
2025-04-30T23:44:52.566Z
Date info (Creation)
2024-10-09T23:08:55
Date info (Revision)
2025-04-30T23:45:09.998Z

Metadata standard

Title

AU/NZS ISO 19115-1:2014

Metadata standard

Title

ISO 19115-1:2014

Metadata standard

Title

ISO 19115-3

Title

Geoscience Australia Community Metadata Profile of ISO 19115-1:2014

Edition

Version 2.0, September 2018

Citation identifier
http://pid.geoscience.gov.au/dataset/ga/122551

 
 

Overviews

Spatial extent

N
S
E
W


Keywords

Australian Resources Framework EFTF – Exploring for the Future Geophysical Acquisition and Processing Section
theme.ANZRC Fields of Research.rdf
Gravimetrics Magnetism and Palaeomagnetism

Provided by

Access to the portal

Associated resources

Not available