Ngalia Basin hydrogeological inventory

This Ngalia Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus.

The Ngalia Basin is an elongate, east-trending basin over 500 km long and 90 km wide. It occurs mostly in the Northern Territory, with limited occurrence in Western Australia. The Ngalia Basin is an intra-cratonic sedimentary basin in a structural downwarp formed by a faulted asymmetrical syncline. The basin began to form about 850 Ma, and contains a Neoproterozoic to Carboniferous sedimentary succession. Sedimentation ceased in response to the 450 to 300 Ma Alice Springs Orogeny.

The maximum stratigraphic thickness of the Ngalia Basin is about 5000 m. The basin contains mainly arenaceous sedimentary rocks, with lesser fine-grained rock types and some carbonates. Fining upwards sedimentary cycles are commonly preserved and capped by calcite-cemented fine-grained sandstone and siltstone. Tectonic events disrupted deposition during basin evolution and led to at least ten unconformities. There are many disconformable contacts, with angular unconformities common in areas with abundant faulting.

The upper-most arkosic sandstone formations in the Ngalia Basin are the Mount Eclipse Sandstone and the Kerridy Sandstone. These units have an aggregate thickness of several hundreds of metres and are the main aquifers within the Ngalia Basin sequence. There is some interstitial porosity, especially in the Mount Eclipse Sandstone, although joints and fissures associated with faulting provide significant secondary permeability. These aquifers provide good supplies of potable to brackish groundwater, and supply the community borefield at Yuendumu.

The Ngalia Basin is almost entirely concealed by Cenozoic cover, including Palaeogene-Neogene palaeovalley, lake and alluvial fan sediment systems and Quaternary aeolian sands. Shallow aquifers with brackish to potable water occur in many palaeovalleys sediments overlying the basin.

Identification info

Date (Creation): 2023-09-01

Date (Publication): 2023-09-28T07:21:33

Citation identifier: Geoscience Australia Persistent Identifier/https://pid.geoscience.gov.au/dataset/ga/148735

Citation identifier: Digital Object Identifier/https://dx.doi.org/10.26186/148735

Cited responsible party

Role	Organisation / Individual Name	Details
Publisher	Commonwealth of Australia (Geoscience Australia)	Voice

Purpose: A thematic summary of the Ngalia Basin. Part of a compendium of consistently compiled summaries that comprise the National Hydrogeological Inventory

Status: Completed

Point of contact

Role	Organisation / Individual Name	Details
Point of contact	Commonwealth of Australia (Geoscience Australia)	Voice
Point of contact	Carey, H.	MEG Internal Contact
Resource provider	Minerals, Energy and Groundwater Division	External Contact

Spatial representation type

Topic category

Geoscientific information
Inland waters
Environment

Extent

Maintenance and update frequency: As needed

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

theme.ANZRC Fields of Research.rdf

Basin Analysis
Environmental Management
PHYSICAL GEOGRAPHY AND ENVIRONMENTAL GEOSCIENCE
EARTH SCIENCES
ENVIRONMENTAL SCIENCES
Hydrogeology
GEOLOGY
ECOLOGY
Land Use and Environmental Planning
Stratigraphy (incl. Biostratigraphy and Sequence Stratigraphy)
Sedimentology

Project

National Groundwater Sytems

Theme

Groundwater

Theme

Exploring for the Future

Theme

National Hydrogeological Inventory

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

Other constraints: (c) Commonwealth of Australia (Geoscience Australia) 2023

Resource constraints

Title: Australian Government Security Classification System

Edition date: 2018-11-01T00:00:00

Website

https://www.protectivesecurity.gov.au/Pages/default.aspx

Classification: Unclassified

Language: English

Character encoding: UTF8

Distribution Information

Distributor contact

Role	Organisation / Individual Name	Details
Distributor	Commonwealth of Australia (Geoscience Australia)	Voice facsimile

OnLine resource: Download the report (pdf) [315 KB]

Download the report (pdf) [315 KB]

Distribution format

Resource lineage

Statement

This document for the National Hydrogeological Inventory was created through the compilation and analysis of various national geospatial datasets and a range of supporting scientific and technical literature. In most cases, the spatial boundary (polygon) for the region was sourced from the Geoscience Australia Geological Provinces 2018 dataset. The geospatial data reported for the region of interest were selected by spatial queries of the region's polygon using Geographic Information System (GIS) applications. A variety of national-scale datasets were assessed for each region, with these data relevant to the study of groundwater, hydrogeology and related social, cultural or environmental characteristics. These data are published by various organisations (mostly Australian Government entities) and include fundamental Australian datasets such as the National Groundwater Information System (NGIS), National Aquifer Framework, Atlas of Groundwater Dependent Ecosystems and the Collaborative Australian Protected Areas Database (CAPAD). A complete list of all data used to develop the National Hydrogeological Inventory, and the various data processing and analysis methods used, will be released as part of a future Geoscience Australia publication focused on the hydrogeological inventory methodology.

The document also contains written summary information about the geology, hydrogeology and related features of the region of interest. These narrative summaries were compiled by Geoscience Australia researchers based on literature review and analysis of a range of scientific and technical publications about the region. The reports use similar document templates to ensure the consistency of information provided across the entire Australian continent.