Revised weathering intensity model of Australia

Weathering is an important process of the Earth’s surface that has a major influence on the chemical and physical properties of rock and soil. The intensity of this process largely controls the degree to which primary minerals are altered to secondary components, including clay and oxide minerals. The degree of surface weathering is particularly important in Australia, where variations in weathering intensity correspond to differences in the nature and distribution of regolith (weathered bedrock and sediments), which mantles approximately 80% of the Australian continent. Here, I use a random forest decision tree machine learning algorithm to first establish a relationship between field estimates of the degree of weathering and a comprehensive suite of covariate or predictive datasets. I then apply this relationship to generate an improved national model of surface to near-surface weathering intensity. Covariates include satellite imagery, terrain attributes, airborne radiometric imagery and mapped geology. The model performs very well, with an r-squared correlation of 0.85 based on 5 K-fold cross-validation on the mean and standard deviation of 300 random forest models. This new weathering intensity model has broad utility for mineral exploration in variably weathered landscapes, agricultural mapping of chemical and physical soil attributes, ecology, and advancing the understanding of weathering processes within the upper regolith.


<b>Citation:</b> Wilford, J., 2020. Revised weathering intensity model of Australia. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.

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Identification info

Date (Creation)
2020-06-29
Date (Publication)
2020-06-29T23:42:05
Citation identifier
ga-dataSetURI/https://pid.geoscience.gov.au/dataset/ga/123671

Citation identifier
Digital Object Identifier/http://dx.doi.org/10.11636/123671

Cited responsible party
Role Organisation / Individual Name Details
Author

Wilford, J.
Status
Completed
Point of contact
Role Organisation / Individual Name Details
Point of contact

Minerals, Energy and Groundwater Division

 External Contact
Point of contact

Commonwealth of Australia (Geoscience Australia)

 Voice
Point of contact

Main, P.

 MEG Internal Contact
Spatial representation type

Extent

Extent

N
S
E
W


Maintenance and update frequency
As needed

Resource format

Title

Administration to complete

Edition

Administration to complete

Resource format

Title

Product data repository: Various Formats

Website

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

Keywords

  • Machine Learning

Discipline

  • geophysics

theme.ANZRC Fields of Research.rdf

  • EARTH SCIENCES

Keywords

  • Weathering

Keywords

  • Regolith

Keywords

  • Data analytics

Project

  • Exploring for the Future

Project

  • EftF

Keywords

  • Surface

Keywords

  • Published_External

Resource constraints

Title

Creative Commons Attribution 4.0 International Licence

Alternate title

CC-BY

Edition

4.0

Website

http://creativecommons.org/licenses/

Access constraints
License
Use constraints
License

Resource constraints

Classification
Unclassified
Language
English
Character encoding
UTF8

Distribution Information

Distributor contact
Role Organisation / Individual Name Details
Distributor

Commonwealth of Australia (Geoscience Australia)

 Voice
OnLine resource

Extended Abstract for download (pdf) [4.7 MB]

Extended Abstract for download (pdf) [4.7 MB]

Distribution format

  • pdf

Resource lineage

Statement

This weathering intensity model is a revision of Wilford, 2012 (A weathering intensity index for the Australian continent using airborne gamma-ray spectrometry and digital terrain analysis. Geoderma 183–184:124–42.) by using a machine learning approach that incorporates addition training site measurments and national datasets.

Hierarchy level
Document

Metadata constraints

Classification
Unclassified

Metadata

Metadata identifier
urn:uuid/d0b9c198-59fa-4db2-9486-a1dabb91549b

Title

GeoNetwork UUID

Type of resource

Resource scope
Document
Name

Revised weathering intensity model of Australia

Alternative metadata reference

Title

Geoscience Australia - short identifier for metadata record with

uuid

Citation identifier
eCatId/123671

Metadata linkage

https://ecat.ga.gov.au:8080/geonetwork/srv/eng//metadata/add5bc51-dd4d-408c-8c1b-deebaacf6efe

Metadata linkage

https://ecat.ga.gov.au/geonetwork/srv/eng//metadata/d0b9c198-59fa-4db2-9486-a1dabb91549b

Metadata linkage

https://ecat.ga.gov.au/geonetwork/srv/eng/catalog.search#/metadata/d0b9c198-59fa-4db2-9486-a1dabb91549b

Metadata linkage

https://ecat.ga.gov.au:80/geonetwork/srv/eng/catalog.search#/metadata/d0b9c198-59fa-4db2-9486-a1dabb91549b

Metadata linkage

https://ecat.ga.gov.au/geonetwork/js/eng/catalog.search#/metadata/d0b9c198-59fa-4db2-9486-a1dabb91549b

Date info (Creation)
2018-05-04T03:37:56
Date info (Revision)
2018-05-04T03:38:12

Metadata standard

Title

AU/NZS ISO 19115-1:2014

Metadata standard

Title

ISO 19115-1:2014

Metadata standard

Title

ISO 19115-3 (Draft Schemas 2015)

Edition date
2015-07-01T00:00:00
Title

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

Edition

Version 2.0, April 2015

 
 

Spatial extent

N
S
E
W


Keywords

Data analytics EftF Exploring for the Future Machine Learning Regolith Surface Weathering geophysics
theme.ANZRC Fields of Research.rdf
EARTH SCIENCES

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