Authors / CoAuthors
Schroder, I.F. | de Caritat, P. | Wallace, L.
Abstract
With the increasing need to extend mineral exploration undercover, new approaches are required to better constrain concealed geology, thereby reducing exploration risk and search space. Hydrogeochemistry is an under-utilised tool that can identify subsurface geology and buried mineral system components, while also providing valuable insights into environmental baselines, energy systems and groundwater resources. With this aim, 238 water bores spanning seven geological provinces in the Northern Territory and Queensland were sampled and analysed for major cations and anions, trace elements, stable and radiogenic isotopes, organic species, and dissolved gases. Here, we demonstrate the utility of this dataset for identifying carbonate-rich aquifers and mineral system components therein. First, we use trends in major element ratios (Ca+Mg)/Cl– and SiO2/HCO–3, then strontium isotope ratios (87Sr/86Sr), to define subpopulations that reflect both spatial and compositional differences. We then apply mafic-to-felsic trace element ratios (V/Cs and Cu/Rb) to reveal elevated base metal concentrations near Lake Woods caused by water–rock interaction with dolerite intrusions. Correlated Sr concentrations between groundwater and surface sediments suggest that the geochemical evolution of these mediums in carbonate-dominated terrains is coupled. Our work develops an approach to guide mineral exploration undercover via the characterisation and differentiation of groundwaters from different aquifers, resulting in improved identification of geochemical anomalies. <b>Citation:</b> Schroder, I., de Caritat, P. and Wallace, L., 2020. The Northern Australia Hydrogeochemical Survey: aquifer lithologies, local backgrounds and undercover processes. 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
134081
Contact for the resource
Point of contact
Resource provider
Point of contact
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia
Digital Object Identifier
Keywords
- ( Project )
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- Exploring For The Future
- ( Project )
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- EFTF
- ( Theme )
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- Hydrogeochemistry
- ( Discipline )
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- groundwater
- ( Discipline )
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- isotopes
- ( Project )
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- Northern Australia Hydrogeochemical Survey
- ( Discipline )
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- carbonate
- ( Discipline )
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- trace elements
- ( Theme )
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- characterise
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- baseline
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- anomaly
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- Mineral Systems
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- Published_External
Publication Date
2020-06-01T23:14:26
Creation Date
2020-01-30T00:00:00
Security Constraints
Legal Constraints
Status
completed
Purpose
Preliminary results from the North Australia Hydrogeochemical Survey as part of EFTF
Maintenance Information
notPlanned
Topic Category
geoscientificInformation
Series Information
Record
Lineage
The North Australia Hydrogeochemical Survey was completed under the Exploring for the Future initiative, The whole dataset will be available from https://pid.geoscience.gov.au/dataset/ga/133888 . The dataset comprises comprehensive groundwater chemistry including, physicochemical parameters, major and trace elements, stable and radiogenic isotopes and dissolved gases.
Parent Information
Extents
[-21.00, -15.00, 132.50, 139.50]
Reference System
Spatial Resolution
Service Information
Associations
Source Information