Otway Basin hydrogeological inventory

This Otway 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 Otway Basin is an elongated sedimentary basin located on the south-east continental margin of Australia. Covering approximately 150,000 square kilometres and stretching about 500 km from South Australia's Cape Jaffa to Victoria's Port Phillip Bay and Tasmania's north-west, most of the basin is offshore, with a smaller portion onshore.

Geological studies of the Otway Basin have primarily focused on its hydrocarbon prospectivity, examining thick Cretaceous aged rocks both onshore and offshore. However, the shallower onshore sedimentary units are more relevant from a groundwater perspective.

The basin's formation began with rifting between the Australian and Antarctic plates during the Late Jurassic, leading to regional subsidence and the development of the elongated sedimentary basin. Following the Cretaceous plate breakup, a passive margin basin formed, which subsequently underwent basin inversion, reverse faulting, and folding, interspersed with extensional periods and normal faulting. This complex evolution, combined with sea level variations and volcanic activity, resulted in numerous sedimentary cycles.

The sedimentary succession in the basin comprises non-marine sediments and volcanic rocks from the Jurassic and early Cretaceous, with a period of tectonic compression interrupting sedimentation during the mid-Cretaceous. The late Cretaceous and Cenozoic sedimentary and volcanic rocks form the primary groundwater-bearing aquifers of the basin, with various sedimentary environments developing in the Neogene and Quaternary. The basin's structural geology is intricate, with numerous basement highs, sub-basins, troughs, and embayments. Fault systems are prevalent, separating tectonic blocks and potentially influencing groundwater flow, offering conduits for inter-aquifer connectivity.

Overall, the Otway Basin's geological history has shaped its hydrocarbon potential and groundwater resources, making it an essential area for ongoing research and exploration in Australia's geological landscape.

Identification info

Date (Creation): 2023-09-01

Date (Publication): 2023-09-28T07:21:36

Citation identifier: Geoscience Australia Persistent Identifier/https://pid.geoscience.gov.au/dataset/ga/148742

Citation identifier: Digital Object Identifier/https://dx.doi.org/10.26186/148742

Cited responsible party

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

Purpose: A thematic summary of the Otway 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
Land Use and Environmental Planning
ENVIRONMENTAL SCIENCES
Sedimentology
Hydrogeology
Stratigraphy (incl. Biostratigraphy and Sequence Stratigraphy)
EARTH SCIENCES
ECOLOGY
GEOLOGY

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) [511 KB]

Download the report (pdf) [511 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.