Characterising earthquake hazard in low seismicity regions is challenging, due to both the inherent lack of data and an incomplete theoretical understanding of the controls on earthquake occurrence away from plate boundaries. In the plate boundary paradigm, elastic rebound theory predicts that cycles of strain accumulation and release will result in regular, or quasiperiodic, recurrence of large earthquakes on individual faults. Analysis of a global compilation of long-term earthquake records shows that this largely holds in plate boundary regions, but begins to break down in intraplate and other low seismicity regions, where more irregular, or aperiodic, earthquake recurrence is observed. In this talk the Otago region of southern New Zealand is used as a case study of a low seismicity region with evidence for aperiodic earthquake recurrence. New paleoearthquake and slip rate data are used to extend the record of faulting back more than 100 ka on two faults, the Hyde and Dunstan faults. These data allow the variability of earthquake rates on these faults to be characterised, with novel Bayesian methods developed to forecast the probability of future earthquakes. Finally, the talk discusses the potential for application of these methods in the Australian context.

For the first time in Australia, ground gravity, airborne gravity/gravity gradiometry, and satellite gravity observations have been combined to produce a series of National Gravity Grids covering an area more than twice the size of Australia. This involved the combination of observations made on the land, in the air, and by satellite - more than 1,800 ground gravity surveys, 14 airborne gravity and gravity gradiometry surveys, and satellite gravity observations. Underpinning this accomplishment is the Australian Fundamental Gravity Network - a series of gravity benchmarks that allow the joining of gravity data into a seamless whole. This presentation will discuss both the utility of the network and how it feeds into the production of the grids, plus the process of creating the national scale grids using such varied sources of gravity data.

Geoscience Australia is increasingly looking to quantify the impact and value of the scientific work that it undertakes. Quantifying impact helps to demonstrate the return on investment from expenditure of government funds in applying geoscience to Australia's most important challenges. Recent analysis has quantified the economic and social benefits arising from precompetitive geoscience under Exploring for the Future, an Australian Government program led by Geoscience Australia that is dedicated to exploring Australia's resource potential and boosting investment. This analysis used the Impact Pathway approach to collect data and information that provides evidence of project and program impacts. The analysis demonstrates that Exploring for the Future is likely to return hundreds of dollars to the Australian economy for every dollar spent on the program. Additional modelling using REMPLAN online analytical tools helps to quantify economic and employment benefits in regional Australia. These approaches to impact assessment are also being adopted across Geoscience Australia in areas ranging from satellite Earth observation to earthquake and tsunami hazard and risk.

Finding new mineral deposits has never been an easy job. Increasing demand for a range of commodities, and depletion of existing deposits through mining, means that new frontiers need to be opened up for mineral exploration. These will largely be in regions where prospective basement rocks are concealed under cover. However, identification of these new frontiers is not a simple task, and exploration is challenging in areas where little is known about the geological context. This talk will outline how new datasets give us fresh eyes with which to view the mineral prospectivity of covered parts of Australia, and how integration of these data at a range of scales provides the framework in which to explore and discover new mineral provinces.

"History provides a limited picture of what can happen from tropical cyclones (TCs). Take the example of Port Hedland or Townsville, with limited numbers of close TC impacts, especially in recent decades, where many communities have gone through rapid growth. How could emergency services in these towns prepare adequately for a major TC strike with no recent experience? How do they know if they have sufficient resources? Will they need to call in resources from other regions or further afield? In this presentation, we will discuss two parts of this problem – developing plausible scenarios of TCs for use in exercises and then evaluating the impacts of a selection of these events to guide planning and response actions for emergency services. GA’s Tropical Cyclone Hazard Assessment (TCHA) provides the backbone of impact scenario modelling – a stochastic catalogue of 10,000 years of plausible TC events that users can delve into. We connect the scenarios to our extensive built environment data collection and the corresponding vulnerability modelling capability to deliver tangible information on the impacts that as-yet unseen events could deliver to communities around our northern coastline.

Australia’s marine jurisdiction covers over 10 million square kilometres, and we estimate that only 25% of its seafloor has been mapped to the adequate resolution required to support the sustainable development and management of our marine estate. Considering that seabed mapping underpins most aspects of ocean sciences and engineering, and contributes strongly to Australia’s economic, environmental and social values, it is critical that we address this fundamental knowledge gap. AusSeabed was founded three years ago—a cross sector collaborative national program aimed at coordinating ocean mapping efforts to maximise benefits to stakeholders. AusSeabed is working to address many challenges surrounding efficient data acquisition, quality assurance, processing and delivery to various end-users with an aim to eliminate duplication of effort and improve data quality and consistency across sectors. A fundamental component of the AusSeabed program is the design and development of a federated, cloud-based, open-source platform to address the whole supply chain from data acquisition to delivery. Importantly, this work is enabling seamless collation of seabed mapping datasets and their integration with other marine data types from a variety of previously isolated and inaccessible holdings. Strong community commitment and a powerful resonance with stakeholders have driven rapid program growth and are a testament to the value of deliberate and effective collaboration for national benefit. This presentation will give an overview of AusSeabed’s current progress, highlights and forward plan.

Australia, like the rest of the world, is forward looking and implementing a range of initiatives to support its transition to a lower carbon future. This presentation will focus on emerging energy resource commodities that have placed Australia on its path to a low carbon economy and how Geoscience Australia’s work program supports the industry’s adaptation to the required change in energy mix. Starting with an overview of Australia’s oil & gas exploration history, the talk will highlight the many significant discoveries, the remaining resource potential and the emergence of new energy resource commodities.

As the world’s largest archipelagic country in Earth’s most active tectonic region, Indonesia faces a substantial earthquake and tsunami threat. Understanding this threat is a challenge because of the complex tectonic environment, the paucity of observed data and the limited historical record. Here we combine information from recent studies of the geology of Indonesia’s Banda Sea with Global Positioning System observations of crustal motion and an analysis of historical large earthquakes and tsunamis there. We show that past destructive earthquakes were not caused by the supposed megathrust of the Banda outer arc as previously thought but are due to a vast submarine normal fault system recently discovered along the Banda inner arc. Instead of being generated by coseismic seafloor displacement, we find the tsunamis were more likely caused by earthquake-triggered submarine slumping along the fault’s massive scarp, the Weber Deep. This would make the Banda detachment representative not only as a modern analogue for terranes hyper-extended by slab rollback but also for the generation of earthquakes and tsunamis by a submarine extensional fault system. Our findings suggest that low-angle normal faults in the Banda Sea generate large earthquakes, which in turn can generate tsunamis due to earthquake-triggered slumping.

Exploring for the Future is an Australian Government program led by Geoscience Australia that aims to drive investment in the resources and agricultural sectors by providing industry and land and water managers with pre-competitive data about potential mineral, energy and groundwater resources. The Australian Government invested $100 million in the first phase of the Exploring for the Future program in 2016. In June 2020, the Australian Government announced a $125 million extension and expansion of the program, bringing their total investment to $225 million to date. Exploring for the Future is building on Geoscience Australia's deep domain knowledge to generate new science and challenge the frontiers of resource exploration. Eight new projects will include the southern half of the continent, with a focus on two potentially resource-rich corridors that stretch across the country. Unlocking these new resource corridors will provide ongoing economic and employment growth across a wide range of regional areas.

Studies of three global sediment-hosted zinc provinces (Mt Isa, Australia; Northern Cordillera, Canada/USA; Irish Midlands, Ireland) indicate that deposits in all three provinces are associated with gradients in many geological parameters. These include lead isotopes, the depth of the lithosphere-asthenosphere boundary, upward-continued gravity and magnetotellurics data. These gradients are interpreted to mark major cratonic boundaries, or edges, that control the distribution of these deposits in space and in time. Studies of the Mt Isa Province indicate that regional alteration has caused extensive loss of zinc, copper and cobalt, potentially providing more than sufficient metal for the known deposits. Moreover, in some cases, metal loss corresponds to changes in rock properties, possibly enabling regional mapping of zones of metal loss using geophysical data.