Geoscience Australia has produced an Atlas of Australian earthquake scenarios (the Atlas) to support planning and preparedness operations for emergency management agencies. The Atlas provides earthquake scenarios represent realistic “worst-case” events that may impact population centres around Australia. Such scenarios may also support seismic risk assessments for critical infrastructure assets to inform remediation actions that could be taken to improve resilience to rare seismic events in Australia. The Atlas of seismic scenarios uses the underlying science and data of the 2018 National Seismic Hazard Assessment (NSHA18) to identify the magnitudes and epicentre locations of these hypothetical earthquakes. Locations and magnitudes of earthquake scenarios are based upon deaggregation of the NSHA18 hazard model. The USGS ShakeMap software is used to produce ground motion intensity fields with the shaking levels being modified by seismic site conditions mapped at a national scale. Fault sources are incorporated into the Atlas where the magnitude of a given scenario exceeds a threshold magnitude of 6.0 and where the rupture length is likely to be longer than 10 km. If a scenario earthquake is located near a known fault within the Australian Neotectonic Features database, a partial or full-length rupture is modelled along the mapped fault. The Atlas generated two scenarios for each of the160 localities across Australia. The scenarios are based on some of the most likely earthquake magnitude-distance combinations estimated at each site. Output products include shaking contours for a range of intensity measures, including peak acceleration and velocity, as well as response spectral acceleration for 0.3, 1.0 and 3.0 seconds. Also included are raster images and the associated metadata used for generating the scenarios.

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

This paper reports efforts to improve the knowledge of the vulnerability to riverine inundation of domestic housing types found in the Brisbane Ipswich area of Queensland. Riverine inundation is inundation by slowing rising river water where the water velocity is sufficiently low as not to cause velocity-related damage. Generic housing types are derived from surveyed exposure and analytical vulnerability relationships are developed from assessments of repair works at different inundation depths and compared to the results of a postal survey of dwellings affected by flooding in January, 2011.

To determine the magnitude of severe wind gust hazard due to thunderstorm downbursts using regional climate model output and analysis of observed data (including radar reflectivity and proximity soundings).

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.

Modelling tropical cyclone Yasi using TCRM

A community Safety Capbility Flyer was produced to showcase the work undertaken in the Community Safety Value Stream. The flyer includes an introduction to the Community Safety Value Stream, case studies of the work Geoscience Australia does in this space and information on how to engage with Geoscience Australia via the products, tools, models and applications that are produced. This flyer is intended for use a conferences and where promotional material would beneficial to showcase the work undertaken at Geoscience Australia such as the Floodplain Management Association Conference on 19-22 May 2015.

The Australian Flood Studies Database is available on line by Geoscience Australia via the Australian Flood Risk Information Portal. 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.

At its nearest, northern Australia is just over 400 km from an active convergent plate margin. This complex and unique tectonic region combines active subduction and the collision of the Sunda-Banda Arc with the Precambrian North Australian Craton (NAC) near the Timor Trough and continues through to the New Guinea Highlands. Ground-motions generated from earthquakes on these structures have particular significance for northern Australian communities and infrastructure projects, with several large earthquakes in the Banda Arc region having caused ground-shaking-related damage in the northern Australian city of Darwin over the historical period. There are very few, if any, present-day tectonic analogs where cold cratonic crust abuts a convergent tectonic margin with subduction and continent-continent collision. Ground motions recorded from earthquakes in typical subduction environments are highly attenuated as they travel through young sediments associated with forearc accretionary prisms and volcanic back-arc regions. In contrast, seismic energy from earthquakes in the northern Australian plate margin region are efficiently channelled through the low-attenuation NAC, which acts as a waveguide for high-frequency earthquake shaking. As such, it is difficult to select models appropriate to the region for seismic hazard assessments. The development of a far-field ground-motion model to support future seismic hazard assessments for northern Australia is discussed. In general, the new model predicts larger ground motions in Australia from plate margin sources than models used for the 2018 National Seismic Hazard Assessment of Australia, none of which were considered fully appropriate for the tectonic environment. Short-period ground motions are strongly dependent on hypocentral depth and are significantly higher than predictions from commonly-used intraslab ground-motion models at comparable distances. The depth dependence in ground motion diminishes with increasing spectra periods. <b>Cite this article as</b> Allen, T. I. (2021). A Far-Field Ground-Motion Model for the North Australian Craton from Plate-Margin Earthquakes, <i>Bull. Seismol. Soc. Am. </i><b> 112</b>, 1041–1059, doi: 10.1785/0120210191

As part of the 2018 National Seismic Hazard Assessment (NSHA), we compiled the geographic information system (GIS) dataset to enable end-users to view and interrogate the NSHA18 outputs on a spatially enabled platform. It is intended to ensure the NSHA18 outputs are openly available, discoverable and accessible to both internal and external users. This geospatial product is derived from the dataset generated through the development of the NSHA18 and contains uniform probability hazard maps for a 10% and 2% chance of exceedance in 50 years. These maps are calculated for peak ground acceleration (PGA) and a range of response spectral periods, Sa(T), for T = 0.1, 0.2, 0.3, 0.5, 1.0, 2.0 and 4.0 s. Additionally, hazard curves for each ground-motion intensity measure as well as uniform hazard spectra at the nominated exceedance probabilities are calculated for key localities.