Digital soil mapping of lithium in Australia  


Authors / CoAuthors

Ng, W. | Minasny, B. | McBratney, A. | de Caritat, P. | Wilford, J.

Abstract

<div>With a higher demand for lithium (Li), a better understanding of its concentration and spatial distribution is important to delineate potential anomalous areas. This study uses a digital soil mapping framework to combine data from recent geochemical surveys and environmental covariates to predict and map Li content across the 7.6 million km2 area of Australia. Soil samples were collected by the National Geochemical Survey of Australia at a total of 1315 sites, with both top (0–10 cm depth) and bottom (on average 60–80 cm depth) catchment outlet sediments sampled. We developed 50 bootstrap models using a Cubist regression tree algorithm for both depths. The spatial prediction models were validated on an independent Northern Australia Geochemical Survey dataset, showing a good prediction with an RMSE of 3.82 mg kg-1 for the top depth. The model for the bottom depth has yet to be validated. The variables of importance for the models indicated that the first three Landsat bands and gamma radiometric dose have a strong impact on Li prediction. The bootstrapped models were then used to generate digital soil Li prediction maps for both depths, which could select and delineate areas with anomalously high Li concentrations in the regolith. The map shows high Li concentration around existing mines and other potentially anomalous Li areas. The same mapping principles can potentially be applied to other elements.&nbsp;</div> <b>Citation:</b> Ng, W., Minasny, B., McBratney, A., de Caritat, P., and Wilford, J.: Digital soil mapping of lithium in Australia, <i>Earth Syst. Sci. Data</i>, 15, 2465–2482, https://doi.org/10.5194/essd-15-2465-2023, <b>2023</b>.

Product Type

document

eCat Id

147254

Contact for the resource

  Resource provider

 

  Point of contact

Commonwealth of Australia (Geoscience Australia)  
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia

  Point of contact

 
Contact instructions
MEG

Keywords

( Project )
  • National Geochemical Survey of Australia
( Project )
  • EFTF – Exploring for the Future
  • digital soil mapping
  • lithium
  • machine learning
  • critical element
theme.ANZRC Fields of Research.rdf
  • Inorganic geochemistrySoil chemistry and soil carbon sequestration (excl. carbon sequestration science)
  • Published_External

Publication Date

2023-07-20T01:55:20

Creation Date

2022-09-22T16:00:00

Security Constraints

Australian Government Security Classification System    

Classification - unclassified

Legal Constraints

Creative Commons Attribution 4.0 International Licence    

Use - license otherRestrictions

Status

completed

Purpose

Publication in peer reviewed scientific journal

Maintenance Information

asNeeded

Topic Category

geoscientificInformation

Series Information

Earth System Science Data Vol 15, issue 6 2165-2482

Lineage

<div>Using data from the National Geochemical Survey of Australia http://dx.doi.org/10.11636/Record.2011.020 </div>

Parent Information

Extents

[-44.00, -9.00, 112.00, 154.00]

Reference System

Spatial Resolution

Service Information

Associations

Association Type - hadDerivation

National Geochemical Survey of Australia: The Geochemical Atlas of Australia    

eCat Identifier - 71973,

UUID - a4a1ac2e-0a2c-653b-e044-00144fdd4fa6

Association Type - hadDerivation

Geochemical map of Australia (First Edition) - Li (lithium) series    

eCat Identifier - 71889,

UUID - a3ac05d0-c761-0fe3-e044-00144fdd4fa6

Downloads and Links

Link to Journal  

Source Information