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  • Many mapped faults in the south-eastern highlands of New South Wales and Victoria are associated with apparently youthful topographic ranges, suggesting that active faulting may have played a role in shaping the modern landscape. This has been demonstrated to be the case for the Lake George Fault, ~25 km east of Canberra. The age of fluvial gravels displaced across the fault indicates that relief generation of approximately 250 m has occurred in the last ca. 4 Myr. This data implies a large average slip rate by stable continental region standards (~90 m/Myr assuming a 45 degree dipping fault), and begs the question of whether other faults associated with relief in the region support comparable activity rates. Preliminary results on the age of strath terraces on the Murrumbidgee River proximal to the Murrumbidgee Fault are consistent with tens of metres of fault activity in the last ca. 200 kyr. Further south, significant thicknesses of river gravels are over-thrust by basement rocks across the Tawonga Fault and Khancoban-Yellow Bog Fault. While these sediments remain undated, prominent knick-points in the longitudinal profiles of streams crossing these faults suggest Quaternary activity commensurate with that on the Lake George Fault. More than a dozen nearby faults with similar relief are uncharacterised. Recent seismic hazard assessments for large infrastructure projects concluded that the extant paleoseismic information is insufficient to meaningfully characterise the hazard relating to regional faults in the south-eastern highlands, despite the potential for large earthquakes alluded to above. While fault locations and extents remain inconsistent across scales of geologic mapping, and active fault lengths and slip rates remain largely unquantified, the same conclusion may be drawn for other scales of seismic hazard assessment.

  • Indonesia is one of the most disaster prone countries in the world due to its hazard profile and high population exposure. Despite its risk profile, disaster management has not traditionally been informed by best available information. Since 2008, the Australian and Indonesian governments have partnered to increase the use of science and technology in Indonesia to support decision making in disaster management. Our partnership has concentrated on strengthening the evidence base for informed disaster management by improving: - hazard information for earthquake, tsunami, volcano and flood - spatial data for exposure (population, building, roads and infrastructure) - decision support tools such as InaSAFE that assist disaster managers to combine hazard and exposure data to inform disaster response and management. We have worked alongside technical and disaster management agencies, universities, non-government organisations and the private sector to develop Indonesian capacity to manage disasters and institutionalise best-practices. Partnerships have facilitated science-to-policy and science-to-programming outcomes in disaster management that help people prepare for, respond to and recover from crises. Ten years is a good time for a partnership to form, blossom and deliver effective and sustainable changes. The achievements over this time are too many to list in entirety. Science and Technology for Disaster Management merely scratches the surface to highlight the most significant achievements. There is a tendency in doing so to focus on achievements over the last three years. In most cases the achievements of this later period of the program have only been possible because they have built on and extended the achievements of the former seven years. Science and Technology for Disaster Management demonstrates how our collaboration has increased the use of science and technology in Indonesian disaster management by developing new knowledge and enhancing capacity, both within the scientists and within policy and decision makers. In doing so, tangible policies have been developed and implemented and practices have changed. The program has helped to strengthen relationships between agencies within Indonesia and also between Indonesia and Australia in the areas of disaster management and science more broadly. New relationships manifest as distinct government-to-government collaborations and strong peer-to-peer links.

  • Strong surface wind gusts and heavy rain are meteorological hazards that are predominantly produced by storms such as east coast lows, tropical cyclones or thunderstorms. Interest in these hazards from a response agency point of view lies in their impact on the natural and built environment. At present, weather forecast models still predict mostly 'raw' meteorological output such as surface wind speeds at certain times, or rain accumulations over a specified period. This model output needs to be combined with exposure and vulnerability information to translate the forecast hazard into predicted impact. The Bushfire and Natural Hazards CRC project Impact-based forecasting for the coastal zone: East-Coast Lows attempts to demonstrate a pilot capability to deliver impact forecasts for residential housing from an ensemble of weather prediction models runs. The project is a collaborative effort between the Australian Bureau of Meteorology and Geoscience Australia. The project is initially focusing on the wind and rainfall impact from the 20-22 April 2015 east coast low event in NSW. The wind and rainfall hazard data are provided by a 24-member ensemble of the ACCESS model on a 1.3 km grid, with damage data acquired from NSW State Emergency Services (SES) and the Emergency Information Coordination Unit (EICU) for the 2015 event. We will show that the multi-hazard nature of an east coast low event makes attributing the observed building damage to a single hazard difficult. Wind damage to residential housing in this case is largely due to tree fall. This 'damage-by-intermediary' mechanism requires not just the knowledge of building properties in an exposed area, but also additional knowledge of the surrounding vegetation and its response to strong winds. We will discuss enhancements to the SES/EICU damage survey templates that would lead to improvements in the development of the hazard-damage relationships.

  • The Geological Survey of Canada's 5th Generation seismic hazard model for Canada forms the basis for the seismic design provisions of the 2015 National Building Code of Canada (NBCC). We deaggregate the seismic hazard results for selected cities to help understand the relative contributions of the earthquake sources in terms of distance and magnitude. Deaggregation for a range of probabilities and spectral accelerations (Sa) from 0.2 to 10.0 seconds is performed to examine in detail the hazard for two of Canada's largest urban centres at highest risk, Vancouver in the west and Montréal in the east. A summary table of deaggregated seismic hazard is provided for other selected Canadian cities, for Sa(0.2), Sa(2.0) and peak ground acceleration (PGA) at a probability of exceedence of 2%/50 years. In most cases, as the probability decreases, the hazard sources closer to the site dominate. Larger, more distant earthquakes contribute more significantly to hazard for longer periods than shorter periods. The deaggregations allow better-informed choices of scenario events and for the selection of representative time histories for engineering design.

  • Geoscience Australia is currently drafting a new National Earthquake Hazard Map of Australia using modern methods and models. Among other applications, the map is a key component of Australia's earthquake loading code AS1170.4. In this paper we provide a brief history of national earthquake hazard maps in Australia, with a focus on the map used in AS1170.4, and provide an overview of the proposed changes for the new map. The revision takes advantage of the significant improvements in both the data sets and models used for earthquake hazard assessment in Australia since the original maps were produced. These include: - An additional 20+ years of earthquake observations - Improved methods of declustering earthquake catalogues and calculating earthquake recurrence - Ground motion prediction equations (i.e. attenuation equations) based on observed strong motions instead of intensity - Revised earthquake source zones - Improved maximum magnitude earthquake estimates based on palaeoseismology - The use of open source software for undertaking probabilistic seismic hazard assessment which promotes testability and repeatability The following papers in this session will address in more detail the changes to the earthquake catalogue, earthquake recurrence and ground motion prediction equations proposed for use in the draft map. The draft hazard maps themselves are presented in the final paper.

  • The Philippine Institute of Volcanology and Seismology (PHIVOLCS) and Geoscience Australia (GA) have developed a long-term partnership in order to better understand and reduce the risks associated with earthquake hazards in the Philippines. The Project discussed herein was supported by the Australian Agency for International Development (AusAID). Specifically, this partnership was designed to enhance the exposure and damage estimation capabilities of the Rapid Earthquake Damage Assessment System (REDAS), which has been designed and built by PHIVOLCS. Prior to the commencement of this Project, REDAS had the capability to model a range of potential earthquake hazards including ground shaking, tsunami inundation, liquefaction and landslides, as well as providing information about elements at risk (e.g., schools, bridges, etc.) from the aforementioned hazards. The current Project enhances the exposure and vulnerability modules in REDAS and enable it to estimate building damage and fatalities resulting from scenario earthquakes, and to provide critical information to first-responders on the likely impacts of an earthquake in near real-time. To investigate this emergent capability within PHIVOLCS, we have chosen the pilot community of Iloilo City, Western Visayas. A large component of this project has been the compilation of datasets to develop building exposure models, and subsequently, developing methodologies to make these datasets useful for natural hazard impact assessments. Collection of the exposure data was undertaken at two levels: national and local. The national exposure dataset was gathered from the Philippines National Statistics Office (NSO) and comprises basic information on wall type, roof type, and floor area for residential buildings. The NSO census dataset also comprises crucial information on the population distribution throughout the Philippines. The local exposure dataset gathered from the Iloilo City Assessors Office includes slightly more detailed information on the building type for all buildings (residential, commercial, government, etc.) and appears to provide more accurate information on the floor area. However, the local Iloilo City dataset does not provide any information on the number of people that occupy these buildings. Consequently, in order for the local data to be useful for our purposes, we must merge the population data from the NSO with the local Assessors Office data. Subsequent validation if the Iloilo City exposure database has been conducted through targeted foot-based building inventory surveys and has allowed us to generate statistical models to approximate the distribution of engineering structural systems aggregated at a barangay level using simple wall and roof-type information from the NSO census data. We present a comparison of the national and local exposure data and discuss how information assembled from the Iloilo City pilot study - and future study areas where detailed exposure assessments are conducted - could be extended to describe the distribution of building stock in other regions of the Philippines using only the first-order national-scale NSO data. We present exposure information gathered for Iloilo City at barangay level in a format that can be readily imported to REDAS for estimating earthquake impact.

  • The service contains the Australian Coastal Geomorphology Landform Type Classifications, used to support a national coastal risk assessment. It describes the location and extent of landform types identifiable at scales between 1:250,000 and 1:25,000. It describes the landform types present in either erosional or dispositional environments.

  • The use of Interferometric Synthetic Aperture Radar (InSAR) to monitor volcano hazards by detecting ground deformation has been demonstrated in numerous cases around the world. This report presents an investigation of the feasibility of using InSAR as a broad scale volcano-monitoring tool in Papua New Guinea (PNG). This type of ongoing broad-scale monitoring would be a significant leap forward compared to the majority of past applications of InSAR for volcano monitoring, which have been sporadic and often conducted in hindsight. A major focus of this study was the development of open-source InSAR analysis software which makes it easier to implement in developing countries where resources may be limited. The environmental conditions of PNG, such as steep topography, dense vegetation and the moist, turbulent atmosphere pose significant challenges to volcano monitoring using InSAR. On the other hand, the remoteness of many of the volcanoes and the limited geophysical resources currently employed to monitor them, makes a broad-scale InSAR monitoring system an attractive proposition. The viability of InSAR as an ongoing tool for broad-scale volcano monitoring in PNG is constrained by the future availability of L-band Synthetic Aperture Radar (SAR) satellite imagery. The ALOS-2 mission should meet the data requirements of a broad-scale volcano monitoring programme. However, the present cost of ALOS data is prohibitive to ongoing monitoring, given the large volume of data required. The planned ALOS-2 mission will acquire SAR data with even higher temporal resolution, but this will be of little use to InSAR monitoring unless it is available at a cost conducive to regular access. At present, the greatest single barrier to a broad-scale InSAR monitoring system is the prohibitive cost of obtaining the required SAR imagery. To improve the accessibility of InSAR processing software to those in developing countries, the InSAR processing workflow that has been developed in this study is open source, being based on the GMTSAR package. In addition the interface has been simplified and a greater level of automation has been implemented to reduce the training required to become operational. The system has been designed to deal with the large volume of data processing required in a broad-scale volcano monitoring operation by parallelizing the most computationally intensive parts of the workflow. A case study of the Rabaul caldera demonstrates that L-band SAR interferometry can overcome many of the challenges of applying InSAR in PNG. However, continued development is required to enable time-series InSAR analysis. This would help to resolve the nonlinear nature of volcano deformation events and reduce the impact of spurious atmospheric delay signals. Commercial software is available to meet this requirement but the development of an open source alternative would be desirable to make the platform inclusive of developing countries.

  • This document is intended to provide a record of the participants, program, and discussions held at the Fire Weather and Risk Workshop, held at Peppers Craigieburn in Bowral, from 1st -4th September 2011. The workshop was attended by 77 delegates and was sponsored by the ACT Emergency Services Agency, Geoscience Australia, the Bureau of Meteorology, and the Federal Attorney Generals Department. These proceedings include the: - workshop program - executive summary by the workshop organizers - presentation abstracts (optional) - summaries of presentations and discussions (compiled at the workshop by the session chairs and scribes) - survey of participants- expectations of the workshop (received prior to the workshop) - results of a post-workshop evaluation - list of participants. This document also includes an invited journalistic-styled article by science journalist, Nick Goldie (Senior Deputy Captain, Colinton Rural Fire Brigade, NSW RFS) which provided an independent view on the activities that occurred over the three days.

  • Probabilistic Tsunami Hazard Assessment (PTHA) often proceeds by constructing a suite of hypothetical earthquake scenarios, and modelling their tsunamis and occurrence-rates. Both tsunami and occurrence-rate models are affected by the representation of earthquake slip and rigidity, but the overall importance of these factors for far-field PTHA is unclear. We study the sensitivity of an Australia-wide PTHA to six different far-field earthquake scenario representations, including two rigidity models (constant and depth-varying) combined with three slip models: fixed-area-uniform-slip (with rupture area deterministically related to magnitude); variable-area-uniform-slip; and spatially heterogeneous-slip. Earthquake-tsunami scenarios are tested by comparison with DART-buoy tsunami observations, demonstrating biases in some slip models. Scenario occurrence-rates are modelled using Bayesian techniques to account for uncertainties in seismic coupling, maximum-magnitudes and Gutenberg-Richter b-values. The approach maintains reasonable consistency with the historical earthquake record and spatially variable plate convergence rates for all slip/rigidity model combinations, and facilitates partial correction of model-specific biases (identified via DART-buoy testing). The modelled magnitude exceedance-rates are tested by comparison with rates derived from long-term historical and paleoseismic data and alternative moment-conservation techniques, demonstrating the robustness of our approach. The tsunami hazard offshore of Australia is found to be insensitive to the choice of rigidity model, but significantly affected by the choice of slip model. The fixed-area-uniform-slip model produces lower hazard than the other slip models. Bias adjustment of the variable-area-uniform-slip model produces a strong preference for `compact' scenarios, which compensates for a lack of slip heterogeneity. Thus, both heterogeneous-slip and variable-area-uniform-slip models induce similar far-field tsunami hazard.