The Australian Flood Studies Database is available on line by Geoscience Australia. The database provides metadata on Australian flood studies and information on flood risk with a digital version where available. The purpose of the document is to guide new users in data entry and uploading of flood studies to a level acceptable for inclusion in the database.

In response to the catastrophic flooding in south east Queensland in early 2011 that caused between AUS$5-6 billion damage, the Australian Government initiated the National Disaster Review; an independent review into the insurance arrangements for individuals and businesses for damages and losses due to flood and other natural disasters. The review emphasised that consumers need to be aware of the risks they face, and highlighted the lack of consistency in the collection and provision of flood risk information. In response the Australian Government committed AUS$12 m over 4 years to the National Flood Risk Information Project (NFRIP). NFRIP was established to improve the quality, availability of accessibility of flood information across Australia and commenced in July 2012 with Geoscience Australia as the technical lead and Attorney Generals department taking the policy lead. The project comprises three core activities. 1) Development of the Australia Flood Risk Information Portal (AFRIP; www.ga.gov.au/afrip ), an online flood information portal that provides free access to authoritative flood study information and associated mapping from a central location. Centralising this information will make it easy for the public, engineering consultants, insurers, researchers and emergency managers to find out what flood information and mapping exists and where, and to better understand their risk. 2) Analysis of Geoscience Australia's historic archive of satellite imagery from 1987 to the present to provide an indication of how often surface water has been observed anywhere in Australia over the period of the archive. These Water Observations from Space (WOfS; www.ga.gov.au/wofs ) provide baseline information that can be used when no other flood information is available and an understanding of where surface water may impact assets and utility infrastructure. 3) Improving the quality of future flood information by completing the revision of the Australian Rainfall and Runoff guidelines (ARR; www.arr.org.au ). ARR is a series of national guidelines, methodologies and datasets fundamental for flood modelling that was updated in 1987 and modified 1997. The revised guidelines will provide flood professionals with information and data necessary to produce more accurate and consistent flood studies and mapping into the future. This presentation will provide a brief summary of the NFRIP objectives and progress to date, discuss some of the problems encountered in sourcing and making natural hazard and risk information public, and reflect on the broader challenges in the communication of risk to the wider community.

In 2009 Geoscience Australia (GA), Australia's national geoscience agency, initiated a project to update the National Earthquake Hazard Map for Australia. This talk will summarise the work done by the Earthquake Hazard Section to update the National Earthquake Hazard Maps and will also present the new maps themselves. The maps have mainly been designed to be used as a basis informing Australia's earthquake loading code. However they can also be used to help to improve Australia's ability to better prepare for earthquakes more generally. This talk will provide a brief overview of the work done for this project. Topics to be highlighted in this talk include how we put together a new catalogue of earthquakes for Australia and revised their magnitudes. Our new method for automatically classifying earthquakes as main shocks, foreshocks and aftershocks will also be discussed, as well the new set of earthquake source zones we have produced. In addition, the talk will also discuss new way we have tried to estimate the maximum expected magnitude for earthquakes in Australia from the results of GA's neotectonics program. The completely new set ground motion prediction equations for eastern Australia we have produced will also be presented. Finally, the talk will also show the revised and updated set of earthquake hazard maps based on the latest version of GA's EQRM (Earthquake Risk Model) code. The hazard and spectral curves for selected locations around Australia will be shown and the potential implications for earthquake risk will be briefly discussed. From the 9th International CO2 conference, Beijing 2013

Please note: The data can be downloaded for free in parts. Wind multipliers are factors that transform regional wind speeds to local wind speeds considering local effects of direction, terrain, shielding and topographic influences. In order to assess the local wind hazard (spatial significance in the order 10's of metres), wind multipliers need to be computed, so that the regional wind speeds (order 10 to 100's of kilometres) can be factored to provide local wind speeds. This data package includes terrain, shielding and topographic multipliers for national coverage. It is based on tiles with dimension about 1 by 1 decimal degree in netCDF format. Each multiplier further contains 8 directions. The version 2 dataset was produced using the wind multiplier computation software 2.0. See Geocat 82481.

Internal advice on tsunami, earthquake and severe wind hazards for the Kavieng Port region, derived from large-scale hazard assessments. This advice (refer TRIM D2021-55554) was provided to the Australia Pacific Climate Partnership (APCP) as part of Geoscience Australia's (GA's) contributions to the program. (In confidence report to APCP, not for distribution)

Seismic hazard models, commonly produced through probabilistic seismic hazard analysis, are used to establish earthquake loading requirements for the built environment. However, there is considerable uncertainty in developing seismic hazard models, which require assumptions on seismicity rates and ground-motion models (GMMs) based on the best evidence available to hazard analysts. This paper explores several area-based tests of long-term seismic hazard forecasts for the Australian continent. ShakeMaps are calculated for all earthquakes of MW 4.25 and greater within approximately 200 km of the Australian coastline using the observed seismicity in the past 50 years (1970-2019). A “composite ShakeMap” is generated that extracts the maximum peak ground acceleration “observed” in this 50-year period for any site within the continent. The fractional exceedance area of this composite map is compared with four generations of Australian seismic hazard maps for a 10% probability of exceedance in 50 years (~1/500 annual exceedance probability) developed since 1990. In general, all these seismic hazard models appear to be conservative relative to the observed ground motions that are estimated to have occurred in the last 50 years. To explore aspects of possible prejudice in this study, the variability in ground-motion exceedance was explored using the Next Generation Attenuation-East GMMs developed for the central and eastern United States. The sensitivity of these results is also tested with the interjection of a rare scenario earthquake with an expected regional recurrence of approximately 5,000 - 10,000 years. While these analyses do not provide a robust assessment of the performance of the candidate seismic hazard for any given location, they do provide—to the first order—a guide to the performance of the respective maps at a continental scale. This paper was presented at the Australian Earthquake Engineering Society 2021 Virtual Conference, Nov 25 – 26.

Public concerns have been raised about the potential for induced seismicity as state and territory governments lift moratoriums on hydraulic stimulation activities for the exploration and extraction of unconventional hydrocarbons. The Scientific Inquiry into Hydraulic Fracturing in the Northern Territory articulated the need for a traffic-light system “to minimise the risk of occurrence of seismic events during hydraulic fracturing operations” within the Beetaloo Sub-basin. A temporary seismic network (Phase 1) was deployed in late 2019 to monitor baseline seismic activity in the basin. Based on the data analysed herein (November 2019 – April 2021), no seismic events were identified within the area of interest suggesting that the Beetaloo Sub-basin is largely aseismic. Observations to date indicate that there is potential to identify events smaller than ML=1.5 within the basin. The recent installation of ten semi-permanent stations for continuous real-time monitoring will contribute to ongoing baseline monitoring efforts and support the implementation of an induced seismicity traffic-light system. The outcome of this study will be used to build knowledge about potential human-induced seismic activity in the region that may be associated with unconventional hydrocarbon recovery. This paper was presented at the Australian Earthquake Engineering Society 2021 Virtual Conference, Nov 25 – 26.

Here we undertake a statistical analysis of local magnitudes (ML) calculated using the two real-time earthquake monitoring software platforms use by Geoscience Australia (GA) since 2005, Antelope and Seiscomp. We examine a database of just over 10 years duration, during a period in which both systems were in operation and over 4000 earthquakes were located and magnitudes estimated. We examine the consistency of both single-station and network ML estimates of both systems, with a view toward determining guidelines for combining them into a single catalogue, as well as for determining best practice in the for the estimation of local magnitudes for regions of sparse seismic networks. Once this guidance has been developed, it is the intention of GA to re-process magnitudes for all earthquakes using a consistent approach where digital data are available and can be integrated within the currently-used SeisComP system. This paper was presented at the Australian Earthquake Engineering Society 2021 Virtual Conference, Nov 25 – 26.

The 22 September 2021 (AEST) moment magnitude MW 5.9 Woods Point earthquake was the largest in the state of Victoria’s recorded history. The ground motions were felt throughout the state of Victoria and into neighbouring states New South Wales and South Australia. Minor damage was reported in the city of Melbourne and in some regional towns close to the epicentre. This event was captured on many high-quality recorders from multiple sources, including private, university, and public stations. These recordings provide a rare opportunity to test the validity of some ground motion models thought to be applicable to the southeast region of Australia. This paper presents spectral acceleration and attenuation comparisons of the Woods Point earthquake event to some ground motion models. The results of this paper provide further evidence that the attenuation characteristics of southeastern Australia may be similar to that in central and eastern United States, particularly at shorter distances to the epicentre. This paper was presented at the Australian Earthquake Engineering Society 2021 Virtual Conference, Nov 25 – 26.

The Mwp 6.1 Petermann Ranges earthquake that occurred on 20 May, 2016 in the Central Ranges, NT, is the largest onshore earthquake to be recorded in Australia since the 1988 Tennant Creek sequence. While geodetic and geophysical analyses have characterized the extent of surface rupture and faulting mechanism respectively, a comprehensive aftershock characterization has yet to be performed. Data has been acquired from a 12-station temporary seismic network deployed jointly by the ANU and Geoscience Australia (GA), collected from five days following the mainshock to early October. Taking advantage of enhanced automatic detection techniques using the SeisComP3 real-time earthquake monitoring software within the National Earthquake Alerts Centre (NEAC) at GA, we have developed a comprehensive earthquake catalogue for this mainshock-aftershock sequence. Utilising the NonLinLoc location algorithm combined with a Tennant Creek-derived velocity model, we have preliminarily located over 5,800 aftershocks. With additional spatio-temporal analyses and event relocation, our objective will be to use these aftershocks to help delineate the geometry of the headwall rupture along the Woodroffe Thrust. These high-resolution aftershock detection techniques are intended to be implemented in real-time within the NEAC following future significant Australian intraplate earthquakes. This paper was presented at the Australian Earthquake Engineering Society 2021 Virtual Conference, Nov 25 – 26.