This Geoscience Australia Record documents the scientific analysis undertaken, and results obtained from geodetic monitoring during the Camden Environmental Monitoring Project (CEMP); a collaborative project undertaken with the New South Wales Department of Planning, Industry and Environment. The aim of the CEMP was to determine the environmental impacts, if any, of active coal seam gas extraction projects in New South Wales. Geodetic monitoring, using satellite radar interferometry (InSAR) and Global Positioning System (GPS) measurements, was used to specifically assess if subsidence (downward vertical land movement) is occurring at the Camden Gas Project; at the time the State’s only actively producing coal seam gas project. To address this question, Geoscience Australia undertook a comprehensive InSAR analysis using data sets from three orbiting radar satellites (ALOS, Envisat and Radarsat-2) covering two periods of time (2006 to 2010, and 2015 to 2019). The outputs of this InSAR analysis are vertical and horizontal ground surface displacement and velocity map products, together with a quantification of the uncertainty of these measurements. Furthermore, a new network of 20 ground geodetic monitoring sites was established in May and June 2016 for the purpose of validating measurements made using InSAR. GPS data was collected at these monitoring sites between July 2016 and June 2019 and processed to obtain 3-dimensional ground surface displacement and velocity measurements. From the analysis of independent InSAR and GPS data sets undertaken during the CEMP, we conclude that no measurable subsidence (i.e. a land movement velocity not greater than 10 mm/yr) has occurred as a result of coal seam gas production in the Camden Gas Project during the time periods of monitoring. However, decimetre-scale horizontal and vertical surface movements have occurred in the Southern Coalfields at the locations of subsurface longwall coal mines. Comparison of the measurements made by InSAR and GPS across the 20-site geodetic monitoring network shows that the two independent geodetic techniques agree within 10 millimetres, even when decimetre-scale movement is occurring. This demonstrates the potential for utilising InSAR for accurate remote monitoring of ground surface movements (including subsidence) at large scales and in the absence of sufficient ground geodetic monitoring infrastructure. The conclusions drawn and the measurements made in this work are specific to the area covered by the CEMP geodetic monitoring project, and are therefore not applicable to other resource extraction activities in other areas because of operational and geological differences from site to site. However, the methods described herein would be applicable to monitoring other resource extraction activities.

The world is turning to the minerals sector to meet sustainable development goals on the path to net zero emissions, buoyed by modern manufacturing. Discovery and development of new and varied mineral deposits is essential to reach these goals. However, despite concerted efforts, exploration success rates are in decline globally. To provide an advantage to Australia’s mineral sector, the Australian Government has significantly invested in precompetitive geoscience to unlock both geographic and conceptual frontiers for further exploration and discovery by private industry. Over the last decade, Geoscience Australia, in collaboration with state/territory geological surveys and academia, has undertaken geoscience data acquisition and analysis at an unprecedented scale aligned with UNCOVER initiative through programs like Exploring for the Future. This strategic move has reversed Australia’s declining market share of global exploration investment, stimulated new minerals industries, led to the discovery of world-class mineral deposits, and opened new undercover provinces for exploration. Here, I highlight some key successes, consider some key challenges, and suggest a future direction for precompetitive geoscience. Australia is at the forefront of mineral systems science underpinned by world-leading standardised national geological and geophysical (i.e. potential field) data coverages. Acquired at increasing resolution over decades, they have been at the vanguard of mineral exploration as they effectively map lateral geological changes yet provide limited and non-unique insights with depth. Recognising mineral deposits are the consequence of large geological systems, a critical step change in the last decade has been a focus on extensive first-pass or framework 3D imaging of the Australian continent through the systematic collection of magnetotelluric (AusLAMP), passive seismic (AusArray) and airborne electromagnetic (AusAEM) data, supplemented by higher fidelity deep reflection seismic profiles. Aided by significant advances in geophysical processing, Bayesian inference and big data analytics, when integrated with classic geoscience these datasets are revealing new first-order controls on mineralisation and identifying new exploration opportunities. Examples include discovery of lithospheric thickness controls on sediment-hosted base-metal deposits, clear scale reduction approaches to targeting iron oxide-copper-gold systems using electrical methods and mapping source rocks of hydrothermal systems. Using statistical modelling, the predictive power of each dataset or derivative can be assessed allowing an unbiased national view of Australia’s mineral potential to emerge. Importantly, these advances are coupled with recommencement of stratigraphic drilling programs to test inference and demonstrably reduce risk of exploring in frontier regions. Systematic quantitative mineral potential analysis rapidly highlights the importance of data consistency, completeness, and the robustness of validation datasets and in so doing reaffirms the critical role geological surveys play as custodians of this information. The diversification of mineral demand to include critical minerals has both leveraged this information to identify new types of mineral deposits but also highlights the youthfulness of mineral systems science. In response there are growing international efforts to grow understanding of minerals systems science for all elements to enable exploration for critical minerals and realise secondary prospectivity of mine waste. The wave of 3D imaging of Australia is developing a framework 3D digital twin and national scale mineral potential models are emerging. The challenge for precompetitive geoscience is to strategically infill this coverage to further accelerate exploration and development by industry. However, given competing land use claims and increasing environmental, social and governance (ESG) requirements on the minerals sector, success requires a common understanding of subsurface geology across minerals, energy and groundwater industries, which dovetails with surficial, social and governance datasets. Delivery of such integrated subsurface understanding is an exciting and vital challenge for geological surveys and their collaborators.