Authors / CoAuthors
Klöcking, M. | Czarnota, K. | Champion, D.C. | Jaques, A.L. | Davies, D. R.
Abstract
Cratonic margins host many of the natural resources upon which our society depends. Despite this, little is known about the dynamic evolution of these regions and the stability of substantial steps in plate thickness that delineate their boundaries with adjacent mantle. Here, we investigate the spatio-temporal evolution of Australian cratonic lithosphere and underlying asthenospheric mantle by using the geochemical composition of mafic volcanic or shallow intrusive rocks preserved throughout the continent’s history. We have collated a large database of mafic samples that were screened to remove data affected by crystal fractionation or assimilation of cumulate material. We use forward and inverse modelling of igneous trace element compositions to calculate the depth and extent of melting for 28 distinct igneous provinces in the North Australian Craton. These results are used to infer mantle potential temperature and lithospheric thickness at the time of eruption. The majority of Paleoproterozoic magmatic events record high mantle potential temperatures of 1350–1450 °C and relatively low lithospheric thicknesses of ≤50 km. In contrast, younger igneous provinces show a gradual decrease in potential temperature and an increase in lithospheric thickness with time. These constraints on the mantle lay the foundation for the development of a quantitative geodynamic understanding of the evolution of the Australian lithosphere and its resources. <b>Citation:</b> Klöcking, M., Czarnota, K., Champion, D.C., Jaques, A.L. and Davies, D. R., 2020. Mapping the cover in northern Australia: towards a unified national 3D geological model. 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.
Product Type
document
eCat Id
135075
Contact for the resource
Point of contact
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia
Point of contact
Resource provider
Digital Object Identifier
Keywords
- theme.ANZRC Fields of Research.rdf
-
- EARTH SCIENCES
- ( Project )
-
- Exploring for the Future
- ( Theme )
-
- Geochemistry
- ( Theme )
-
- Rare Earth Elements
- ( Theme )
-
- Mafic volcanics
-
- EFTF
-
- mantle
-
- geochemistry
-
- inversion
-
- melt
-
- lithosphere
-
- Published_External
Publication Date
2020-06-30T02:32:12
Creation Date
Security Constraints
Legal Constraints
Status
completed
Purpose
EFTF Extended Abstract
Maintenance Information
asNeeded
Topic Category
geoscientificInformation
Series Information
Lineage
Datasets used in this study are based on geochemistry data in the Geoscience Australia OzChem database, state and territory geological surveys and published academic literature. The study was undertaken as part of the Exploring for the Future program.
Parent Information
Extents
[-25.62, -9.82, 109.42, 158.41]
Reference System
Spatial Resolution
Service Information
Associations
Source Information