The Officer Basin in South Australia and Western Australia is the focus of a regional stratigraphic study being undertaken by the Exploring for the Future (EFTF) program, an Australian Government initiative dedicated to increasing investment in resource exploration in Australia. This data release provides new data and discusses the results from a new commissioned petrographic study of rock samples from five wells of the Officer Basin including: GSWA Vines 1, Yowalga 3, Birksgate 1, Giles 1, and Munta 1. Data includes petrography, XRD, thin section scans and photos, as well as petrographic summaries

The Officer Basin spanning South Australia and Western Australia is the focus of a regional stratigraphic study being undertaken as part of the Exploring for the Future (EFTF) program, an Australian Government initiative dedicated to increasing investment in resource exploration in Australia. Despite numerous demonstrated oil and gas shows, the Officer Basin remains a frontier basin for energy exploration with significant uncertainties due to data availability. Under the EFTF Officer-Musgrave Project, Geoscience Australia acquired new geomechanical rock property data from forty core samples in five legacy stratigraphic and petroleum exploration wells that intersected Paleozoic and Neoproterozoic aged intervals. These samples were subjected to unconfined compressive rock strength tests, Brazilian tensile strength tests and laboratory ultrasonic measurements. Petrophysical properties were also characterised via X-ray computerised tomography scanning, grain density and porosity-permeability analysis. Accurate characterisation of static geomechanical rock properties through laboratory testing is essential. In the modern exploration environment, these datasets are a precompetitive resource that can simplify investment decisions in prospective frontier regions such as the Officer Basin. Appeared in The APPEA Journal 62 S385-S391, 13 May 2022

The Neoproterozoic–Paleozoic Officer Basin, located in South Australia and Western Australia, remains a frontier basin for energy exploration with significant uncertainty due to a paucity of data. As part of Geoscience Australia’s Exploring for the Future (EFTF) program, the objective of this study is to derive the petrophysical properties and characterise potential reservoirs in the Neoproterozoic–Cambrian sedimentary succession in the Officer Basin through laboratory testing, and well log interpretation using both conventional and neural network methods. Laboratory measurements of forty-one legacy core samples provide the relationships between gas permeability, Klinkenberg corrected permeability, and nano-scale permeability, as well as grain density, effective and total porosity for various rock types. Conventional log interpretation generates the volume fraction of shale, effective and total porosity from gamma ray and lithology logs. Self-organising map (SOM) was used to cluster the well log data to generate petrophysical group/class index and probability profiles for different classes. Neural network technology was employed to approximate porosity and permeability from logs, conventional interpretation results and class index from SOM modelling. The Neoproterozoic-Cambrian successions have the potential to host both conventional and tight hydrocarbon reservoirs. Neoproterozoic successions are demonstrated to host mainly tight reservoirs with the range in average porosity and geometric mean permeability of 4.77%-6.39% and 0.00087-0.01307 mD, respectively, in the different sequences. The range in average porosity and geometric mean permeability of the potential Cambrian conventional reservoirs is 14.54%-26.38% and 0.341-103.68 mD, respectively. The Neoproterozoic shales have favourable sealing capacities. This work updates the knowledge of rock properties to further the evaluation of the resource potential of the Officer Basin. Published in The APPEA Journal 2022 <b>Citation:</b> Wang Liuqi, Bailey Adam H. E., Carr Lidena K., Edwards Dianne S., Khider Kamal, Anderson Jade, Boreham Christopher J., Southby Chris, Dewhurst David N., Esteban Lionel, Munday Stuart, Henson Paul A. (2022) Petrophysical characterisation of the Neoproterozoic and Cambrian successions in the Officer Basin. <i>The APPEA Journal</i><b> 62</b>, 381-399. https://doi.org/10.1071/AJ21076

Geoscience Australia’s Exploring for the Future Program is investigating the mineral, energy and groundwater resource potential of sedimentary basins and basement provinces in northern Australia and parts of South Australia. A key challenge in exploring Australian onshore sedimentary basins is that these are often areas with limited seismic data coverage to image the sub-surface structural and stratigraphic architecture. Consequently, well logs are often the main data sets that are used to understand the sub-surface geology. Where good seismic data coverage is available, a considerable amount of time is generally required to undertake an integrated interpretation of well and seismic data. The primary aim of this study is to develop a methodology for visualising the three-dimensional tectonostratigraphic architecture of sedimentary basins using just well data, which can then be used to quickly screen areas warranting more detailed studies of resource potential. A workflow is documented which generates three-dimensional well correlations using just well formation tops to visualise the regional structural and stratigraphic architecture of the Amadeus, Canning, Officer and Georgina basins in the Centralian Superbasin. A critical step in the workflow is defining regionally correlatable supersequences that show the spatial linkages and evolution through time of lithostratigraphic units from different basin areas. Thirteen supersequences are defined for the Centralian Superbasin, which were deposited during periods of regional subsidence associated with regional tectonic events. Regional three-dimensional correlation diagrams have been generated to show the spatial distribution of these supersequences, which can be used as a reconnaissance tool for visualising the distribution of key stratigraphic elements associated with petroleum, mineral and groundwater systems. Three-dimensional well correlations are used in this study to redefine the Centralian Superbasin as encompassing all western, northern and central Australian basins that had interconnected depositional systems driven by regional subsidence during one or more regional tectonic events between the Neoproterozoic and middle Carboniferous. The Centralian Superbasin began to form during a series of Neoproterozoic rift-sag events associated with the break-up of the Rodinia Supercontinent at about 830 Ma. Depositional systems in the Amadeus and Officer basins were partially disconnected by an emergent Musgrave Province during these early stages of superbasin evolution. Subsequent regional uplift and erosion of the superbasin occurred during the late Neoproterozoic–early Cambrian Petermann Orogeny. The Officer and Amadeus were permanently disconnected by the uplifted Musgrave Province following this major orogenic event. Rejuvenation of the Centralian Superbasin occurred during middle–late Cambrian extension and subsidence resulting in the generation of several new basins including the Canning Basin. Subsidence during the Ordovician Larapinta Event created an intracontinental seaway that episodically connected the Canning, Amadeus, Georgina and Officer basins to the proto-Pacific Ocean in the east. Fragmentation of the Centralian Superbasin began at the onset of the Alice Springs Orogeny during the Rodingan Event when the uplifted Arunta Region disconnected the Amadeus and Georgina basins. The Rodingan Movement initially disconnected depositional systems between the Canning and Amadeus basins, which promoted the development of a large evaporitic depocentre over the southern Canning Basin. However, these basins subsequently reconnected during the Early Devonian Prices Creek Movement. Complete fragmentation of the Centralian Superbasin occurred during the Late Devonian–middle Carboniferous Pillara Extension Event when the Canning and Amadeus basins became permanently disconnected. Widespread uplift and erosion at the culmination of the Alice Springs Orogeny in the middle Carboniferous resulted in final closure of the Centralian Superbasin.

Geoscience Australia commissioned reprocessing of selected legacy 2D seismic data in the Officer Basin in South Australia as part of the Exploring for the Future (EFTF) program. Reprocessing of these data occurred between April 2021 and August 2021. This seismic data release package contains reprocessed data from five surveys acquired between 1966 and 1987. In total it contains approximately 1425 km of industry 2D reflection seismic data comprising of 25 lines from 5 separate vintages. The seismic surveys include the Serpentine Lakes Reconnaissance Survey, 1966; the Everard Survey, 1974; the Marla Bore Survey, 1984; the Ungoolya, Giles and Marla-Byilkaoora Surveys, 1985; and the Amoco Officer Basin Survey, 1987 and cover areas within the Officer Basin in South Australia. The objective of the seismic reprocessing was to produce processed 2D land seismic reflection datasets using the latest processing techniques to improve continuity and data quality over legacy processing. In particular, the purpose of the reprocessing was to image the structure and stratigraphic architecture of the Neoproterozoic to Paleozoic Officer Basin in this area. All vintages except the 1966 Serpentine lakes survey were processed to Pre-stack Time Migration as well as Post-Stack Time Migration. The 1966 Serpentine Lakes Survey was processed only to Post-Stack Time Migration. <b>The Velseis data package is available on request from clientservices@ga.gov.au - Quote eCat# 145905</b>

<div>Geoscience Australia’s Onshore Basin Inventories project delivers a single point of reference and creates a standardised national basin inventory that provides a whole-of-basin catalogue of geology, petroleum systems, exploration status and data coverage of hydrocarbon-prone onshore Australian sedimentary basins. In addition to summarising the current state of knowledge within each basin, the onshore basin inventory reports identify critical science questions and key exploration uncertainties that may help inform future work program planning and decision making for both government and industry. Volume 1 of the inventory covers the McArthur, South Nicholson, Georgina, Wiso, Amadeus, Warburton, Cooper and Galilee basins and Volume 2 expands this list to include the Officer, Perth and onshore Canning basins. Under Geoscience Australia’s Exploring for the Future (EFTF) program, several new onshore basin inventory reports are being delivered. Upcoming releases include the Adavale Basin of southern Queensland, and a compilation report addressing Australia’s poorly understood Mesoproterozoic basins. These are supported by value-add products that address identified data gaps and evolve regional understanding of basin evolution and prospectivity, including petroleum systems modelling, seismic reprocessing and regional geochemical studies. The Onshore Basin Inventories project continues to provide scientific and strategic direction for pre-competitive data acquisition under the EFTF work program, guiding program planning and shaping post-acquisition analysis programs.</div>

<div>This report details results and methodology from two hydrochemistry sampling programs performed as part of Geoscience Australia’s Musgrave Palaeovalley Project. The Musgrave Palaeovalley Project is a data acquisition and scientific investigation program based around the central west of Australia. It is aimed at investigating groundwater processes and resources within the Cenozoic fill and palaeovalleys of the region. This project, and many others, have been performed as part of the Exploring for the Future (EFTF) program, an eight-year, $225 million Australian Government funded geoscience data and precompetitive information acquisition program.</div><div>Data released here is from 18 bores sampled for groundwater and tested for a range of analytes including field parameters, major and minor elements, isotopes and trace gases. The sampling methods, quality assurance/quality control procedures, analytical methods and results are included in this report.</div>

This report presents groundwater level information collected during Geoscience Australia’s Musgrave Palaeovalley Project. The Musgrave Palaeovalley Project was conducted as part of Exploring for the Future (EFTF), an Australian Government funded geoscience data and information acquisition program. The eight-year, $225 million program aims to deliver new geoscience data and knowledge to inform decision-making by government, community, and industry on the sustainable development of Australia's mineral, energy, and groundwater resources.</div><div>Groundwater level data was collected during two hydrogeochemical surveys undertaken in March and May 2023 based around the remote communities of Warburton, Kaltukatjara, Wanarn, Blackstone and Jameson in Western Australia and the Northern Territory. Sixteen bores were measured for their groundwater levels. The results are contained herein and within the attached CSV file.

A key challenge in exploring Australian onshore sedimentary basins is limited seismic data coverage. Consequently, well logs are often the main datasets that can be used to understand the subsurface geology. The primary aim of this study was to develop a methodology for visualising the three-dimensional (3D) tectonostratigraphic architecture of sedimentary basins using well data, which can then be used to quickly screen areas warranting more detailed studies of resource potential. This project has developed a workflow that generates 3D well correlations using sequence stratigraphic well tops to visualise the regional structural and stratigraphic architecture of the Amadeus, Canning, Officer and Georgina basins in the Centralian Superbasin. Thirteen Neoproterozoic‒Paleozoic supersequence tops were interpreted in 134 wells. Three-dimensional well correlations provide an effective regional visualisation of the tectonostratigraphic architecture across the main depocentres. This study redefines the Centralian Superbasin as encompassing all western, northern and central Australian basins that had episodically interconnected depositional systems driven by regional subsidence during one or more regional tectonic events between the Neoproterozoic and middle Carboniferous. The Centralian Superbasin began to form during Neoproterozoic extension, and underwent several phases of partial or complete disconnection and subsequent reconnection of depositional systems during various regional tectonic events before final separation of depocentres at the culmination of the Alice Springs Orogeny. Regional 3D correlation diagrams have been generated to show the spatial distribution of these supersequences, which can be used to visualise the distribution of stratigraphic elements associated with petroleum, mineral and groundwater systems. <b>Citation: </b>Bradshaw, B., Khider, K., MacFarlane, S., Rollet, N., Carr, L. and Henson, P., 2020. Tectonostratigraphic evolution of the Centralian Superbasin (Australia) revealed by three-dimensional well correlations. 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.

The Neoproterozoic to Middle Ordovician sediments of the Officer Basin, Australia are difficult to correlate, in part because biostratigraphic studies of acritarchs and stromatolites are localised, isotopic studies are rare, and seismic models are technically challenged by the occurrence of basaltic and halite prone-sections. Hence, the chemostratigraphic framework presented here provides an independent stratigraphic model for the Neoproterozoic to Middle Ordovician sediments of the Officer Basin. A total of six chemostratigraphic mega-sequences have been geochemically defined and assigned to the stratigraphy; these have been further subdivided into twenty-eight chemostratigraphic sequences. The chemostratigraphic zonation has been established upon elemental changes attributed to provenance and climatic variation which can be used for correlation as they convey regional, rather than local, changes in sedimentation. The elemental data reveals that there is lateral variation within the established lithostratigraphy (e.g., within the members of the Observatory Hill and Hussar formations), which is suggestive of localised sediment source input to different areas of the basin. Presented to the 2022 Central Australian Basins Symposium IV (CABS) 29-30 August (https://agentur.eventsair.com/cabsiv/)