From Geoscience Australia
JSON RDF ISO19115-3 XML

Geochemical characterisation of iron-rich regolith materials in the Olary Block of South Australia

ARCHIVED

Created 20/01/2025

Updated 20/01/2025

JSON RDF ISO19115-3 XML

The Olary Block (SA), an inlier of the Palaeoproterozoic Willyama Supergroup, is a target for base-metal and gold exploration. Overburden averaging less than 100 m thick conceals much of its northern part, where an appreciation of iron-rich regolith geochemistry is necessary for evaluating grab samples and rock chips recovered from drilling and for planning follow-up exploration. Geochemical analysis of an exploration suite, and statistical processing (optimised transformations, multivariate trimming, and simultaneous R- and Q-mode principal-components analysis) has enabled us to differentiate four types of iron-rich regolith: gossanous ironstones; banded-iron formations and replacement ironstones; pisolitic ferruginous duricrusts; and lags. The iron-rich regolith generally contains elevated As and Ba, and low Pb. Gossanous ironstones derived from the sulphide-bearing Bimba suite are consistently anomalous in Cu, Zn, As, and in places Pb, Se, U, Mo. Co. Bi , Ba, and Au. A diverse group, the gossanous ironstones show different associations (e.g., Zn-Ba- Pb- Mn , Cu- Zn-As- Mo- Ag- Co- Bi, Cu- As- Mo, and Zn- Cu- As). The iron formations and replacement ironstones are the least geochemically anomalous materials , except for one notable occurrence of anomalous Mn, P, As, and Zn. The pisolitic ferruginous duricrust contains Cu- Zn concentrations of 100-200+ ppm, and anomalous U, Ni, Se, and Ag compared with veneer lags. Detritus, or lags shed from the gossans and ironstones, have a similar chemical signature to their parent material. Veneer lags of ferruginous fragments, pisoliths, and nodules locally mantle the landscape where weathering profiles are preserved, and form a homogeneous group characterised by high Ba and As.

Files and APIs

Tags

Additional Info

Field Value
Title Geochemical characterisation of iron-rich regolith materials in the Olary Block of South Australia
Language eng
Licence notspecified
Landing Page https://devweb.dga.links.com.au/data/dataset/a7a39603-b816-41e2-a765-edd8c3025bc9
Contact Point
Geoscience Australia
clientservices@ga.gov.au
Reference Period 20/04/2018
Geospatial Coverage {"type": "Polygon", "coordinates": [[[138.0, -33.15], [140.94, -33.15], [140.94, -30.52], [138.0, -30.52], [138.0, -33.15]]]}
Data Portal data.gov.au

Data Source

This dataset was originally found on data.gov.au "Geochemical characterisation of iron-rich regolith materials in the Olary Block of South Australia". Please visit the source to access the original metadata of the dataset:
https://devweb.dga.links.com.au/data/dataset/geochemical-characterisation-of-iron-rich-regolith-materials-in-the-olary-block-of-south-austra