This document describes a structure for exchanging information to assist discovery and retrieval/transfer of flood information, including GIS flood mapping data. The draft class model represents metadata, data and summary information that supports the goals of the National Flood Risk Information Project (NFRIP) to improve the quality, consistency and accessibility of flood information. This document describes the data model that will be used to create an application schema.

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

Severe TC Vance was one of the most intense cyclones to impact mainland Australia. The observed damage to buildings could be explained in terms of structural performance of those buildings. Combining the structural vulnerability of housing with an estimate of the maximum wind gusts, we can explore the possible impacts that a repeat of Vance would cause in Exmouth, and compare the outcomes with what occurred in 1999. The analysis of the impacts of TC Vance on present-day Exmouth shows that very few houses would be completely destroyed. Not surprisingly, older houses (pre-1980’s construction era, excluding the US Navy block houses) would dominate those destroyed, and most likely the timber-framed style houses, many of which were substantially damaged in TC Vance. Published in the Australian Journal of Emergency Management July 2019 edition

Heterogeneous distribution of slip during megathrust earthquakes has been shown to significantly affect the spatial distribution of tsunami height in both numerical studies and field observations. This means that tsunami hazard maps generated using uniform slip distributions in their tsunami source models may underestimate tsunami inundation in some locations compared with real events of the same magnitude in the same location. In order to more completely define areas that may be inundated during a tsunami it is important to consider how different possible distributions of slip will impact different parts of the coastline. We generate tsunami inundation maps for the Mentawai Islands, West Sumatra, Indonesia, from a composite suite of possible source models that are consistent with current knowledge of the source region. First, a suite of earthquake source models with randomly distributed slip along the Mentawai Segment of the Sunda Subduction Zone is generated using a k-2 rupture model. From this suite we select source models that generate vertical deformation consistent with that observed in coral palaeogeodetic records of previous ruptures of the Mentawai Segment in 1797 and 1833, minus deformation observed in the 2007 Bengkulu earthquake sequence. Tsunami inundation is then modelled using high resolution elevation data for selected source models and the results compiled to generate a maximum tsunami inundation zone. This method allows us to constrain the slip distribution beneath the Mentawai Islands, where coral palaeogeodetic data is available, while allowing for greater variation in the slip distribution away from the islands, in particular near the trench where large slip events can generate very large tsunami. This method also allows us to consider high slip events on deeper portions of the megathrust between the Mentawai Islands and the Sumatran Mainland, which give greater tsunami inundation on the eastern part of the Mentawai Islands and the west coast of Sumatra compared with near-trench event. By accounting for uncertainty in slip distribution, the resulting hazard maps give a more complete picture of the areas that may be inundated compared with hazard maps derived from a single 'worst case' source model. These maps allow for more robust tsunami evacuation plans to be developed to support immediate community evacuation in response to strong or long-lasting earthquake ground shaking. From the American Geophysical Union Fall Meeting Abstracts

These videos are recordings of online secondary teacher professional learning sessions, delivered by Geoscience Australia’s Education Team. “Can I Fall Down the Cracks?” Plate Tectonic Misconceptions Part 1 This session focused on common misconceptions that are encountered when teaching plate tectonics. The student misconceptions addressed are: 1. We can’t see the tectonic plates (starting at 5:35) 2. The mantle is made of liquid rock (starting at 11:25) 3. The plates move by convection in the mantle (starting at 17:35) 4. When plates collide one always goes under the other (starting at 22:15) 57 minutes total duration, with Q&A with an expert scientist starting at 34 minutes. “Can I Fall Down the Cracks?” Plate Tectonic Misconceptions Part 2 This session focused on common misconceptions that are encountered when teaching hazards associated with plate tectonics. The student misconceptions addressed are: 1. Earthquakes are measured using the Richter scale (starting at 3:15) 2. The magnitude of an earthquake depends on how far away it is (starting at 7:20) 3. Earthquakes can be predicted (starting at 10:52) This section includes a description of Raspberry Shake equipment: low cost earthquake monitoring for the classroom 4. There are no volcanoes in Australia (starting at 18:25) 5. You can surf a tsunami (starting at 24:17) 51 minutes total duration, with Q&A with an expert scientist starting at 37 minutes.

A component of the PNG-Australia Volcanological Services Support (VSS) Project funded by AusAID

In August 2002 the Council of Australian Governments (COAG) reviewed natural disaster relief and mitigation arrangements for Australia (COAG, 2003). In response to the recommendation to “develop and implement a five-year national program of systematic and rigorous disaster risk assessments”, Geoscience Australia (GA) is undertaking a series of national risk assessments for a range of natural hazards. Fundamental to any risk assessment is an understanding of the exposure including the number and type of buildings, businesses, infrastructure and people exposed to the hazard of interest. Presently there is no nationally consistent exposure database in existence for risk assessment purposes. It is important to emphasise that understanding the risks associated with various hazards requires more detailed information than the population and number of structures at a census district level. The understanding of building type, construction (roof and wall) type, building age, number of storeys, business type and replacement value is critical to understanding the potential impact on Australian communities from various hazards. The National Exposure Information System (NEXIS) is aimed at providing nationally consistent and best available exposure information at the building level. It requires detailed spatial analysis and integration of available demographic, structural and statistical data. Fundamentally, this system is developed from several national spatial datasets as a generic approach with several assumptions made to derive meaningful information. NEXIS underpins scenarios and risk assessments for various hazards. Included are earthquakes, cyclones, severe synoptic wind, tsunami, flood and technogenic critical infrastructure failure. It will be integrated with early warning and alert systems to provide real time assessment of damage or forecast the impact for any plausible hazards. This system is intended to provide a relative assessment of exposure from multiple hazards and provide the geographic distribution of exposure for regional planning. This will be at an aggregated census district level now and at a mesh block level in the future. The system is scoped to capture the residential, business (commercial and industrial), and ancillary (educational, government, community, religious, etc.) infrastructure. Currently the NEXIS architecture is finalised and the system provides residential exposure information. The prototype for business exposure is in progress. The system aims to capture ancillary buildings, infrastructure and various critical infrastructure sector exposures in future. More specific building and socio-economic information will be incorporated as new datasets or sources of information become available. The NEXIS will be able to provide the exposure information for the impact analysis for a region. This database will not support a site specific assessment involving one or two buildings and need more specific information about the particular exposure to estimate the risk at micro level. More detailed information suitable for such analysis will be maintained in reference databases.

A short film about a scientific project aimed at enhancing risk analysis capacities for flood, severe wind from tropical cyclones and earthquake in the Greater Metropolitan Manila Area. Manila is one of the world's megacities, and the Greater Metro Manila Area is prone to natural disasters. These events may have devastating consequences for individuals, communities, buildings, infrastructure and economic development. Understanding the risk is essential for implementing Disaster Risk Reduction programs. In partnership with AusAID, Geoscience Australia is providing technical leadership for risk analysis projects in the Asia-Pacific Region. In the Philippines, Geoscience Australia is engaging with Government of the Philippines agencies to deliver the "Enhancing Risk Analysis Capacities for Flood, Tropical Cyclone Severe Wind and Earthquake in the Greater Metro Manila Area" Project.

Indonesia is located in one of the most seismically active regions in the world and often experiences damaging earthquakes. In the past the housing sector has sustained more damage and losses than other sectors due to earthquakes. This is often attributed to the fact that the most common houses in Indonesia are non-engineered, built with poor quality workmanship, poor quality materials and without resilient seismic design features. However little effort has been made to quantify how fragile these houses are, or how the fragility of these houses may vary according to location or wealth. It is not possible to derive empirical fragility functions for Indonesia due to insufficient damage data. The aim of this study is to determine whether existing earthquake fragility functions can be used for common houses in Indonesia. Scenario damage analyses were undertaken several times using different sets of fragility functions for the 2006 Yogyakarta and 2009 Padang events. The simulated damage results were then compared to the damage observed post event to determine whether an accurate damage prediction could be achieved. It was found that the common houses in Yogyakarta and Central Java vary according to age, location and wealth and can be reasonably well represented by existing fragility functions. However, the houses in Padang and surrounding West Sumatra did not vary in a predictable manner and are more fragile than anticipated. Therefore, the fragility of the most common houses in Indonesia is not uniform across the country. This has important implications for seismic damage and risk assessment undertaken in Indonesia. <b>Citation:</b> Weber, R., Cummins, P. & Edwards, M. Fragility of Indonesian houses: scenario damage analysis of the 2006 Yogyakarta and 2009 Padang earthquakes. <i>Bull Earthquake Eng</i> (2024). https://doi.org/10.1007/s10518-024-01930-z

A database of recordings from moderate-to-large magnitude earthquakes is compiled for earthquakes in western and central Australia. Data are mainly recorded by Australian National Seismograph Network (ANSN), complemented with data from temporary deployments, and covering the period of 1990 to 2019. The dataset currently contains 1497 earthquake recordings from 164 earthquakes with magnitudes from MW 2.5 to 6.1, and hypocentral distances up to 1500 km. The time-series data are consistently processed to correct for the instrument response and to reduce the effect of background noise. A range of ground-motion parameters in the time and frequency domains are calculated and stored in the database. Numerous near-source recordings exceed peak accelerations of 0.10 g and range up to 0.66 g, while the maximum peak velocity of the dataset exceeds 27 cm/s. In addition to its utility for engineering design, the dataset compiled herein will improve characterisation of ground-motion attenuation in the region and will provide an excellent supplement to ground-motion datasets collected in analogue seismotectonic regions worldwide. This paper was presented at the Australian Earthquake Engineering Society 2021 Virtual Conference, Nov 25 – 26.