Living with bushfires is a part of life for many Australians. However, bushfire can cause significant losses to economic, social, and environmental assets and values. Decisions about mitigating the harmful impacts of fires on assets and values, as well as operational management of fires, are critical. A Bushfire Risk Assessment Framework (BRAF) is being developed as an output for the Bushfire Cooperative Research Centre (BCRC) project Fire Impact & Risk Evaluation Decision Support Tool (FIRE-DST). The framework will incorporate the computational framework being developed in the FIRE-DST project. The primary driver for the framework is to assist the development of improved, consistent information on bushfire risk that supports effective bushfires risk management. The framework will be designed to encompass the outcomes of other BCRC research projects. It will support various national initiatives such as the NSDR and the Climate Change Adaptation Framework and will address issues arising from the Victorian Bushfires Royal Commission and the 2004 report to COAG 'Report of the National Inquiry on Bushfire Mitigation and Management'. This COAG report examined risk management but did not examine the risk assessment methodology. BRAF focuses on impact and risk assessment for severe and extreme fires. Financial, socio-economic, casualty, political and environmental risks arising from bushfires will be covered by the framework. Roles in the framework are described for a number of stakeholders including jurisdictional agencies, national committees and non government organisations including the private sector and peak industry bodies.

Forest fires or bushfires, as they are called in Australia, are one of the major hazards facing the Australian continent. Chen (2004) rated bushfires as the third largest cause of building damage in Australia during the 20th century. Most of this damage was due to a few extreme bushfire events. The worst of these extreme events, and one of the worst natural disasters in Australian history, occurred in February 2009 when 173 people died and over 2000 houses were destroyed in the Victorian bushfires known as 'Black Saturday' (Bushfire CRC 2009). This study is focused on determining the bushfire hazard associated with communities that are located some distance from the nearest meteorological observing. Further assessment of the bushfire risk to communities can be achieved through the association of bushfire hazard (in the form of return period FFDI) with empirical house loss (Blanchi et al. 2010). In Sanabria et al (2012) we assess the impact of climate change on bushfire hazard using high resolution climate simulations. This study shows that the best interpolation results can be obtained by using a combination of random forest and inverse distance weighting. The interpolated maps using this combination showed physically plausible results and gave the smallest prediction errors.

Geoscience Australia (GA) is currently undertaking the process to update the Australian National Earthquake Hazard Map using modern methods and an extended catalogue of Australian earthquakes. This map is a key component of Australia's earthquake loading code. The characterisation of strong ground-shaking using Ground-Motion Prediction Equations (GMPEs) underpins any earthquake hazard assessment. We have recently seen many advances in ground-motion modelling for active tectonic regions. However, the challenge for Australia - as it is for other stable continental regions - is that there are very few ground-motion recordings from large-magnitude earthquakes with which to develop empirically-based GMPEs. Consequently, we need to consider other numerical techniques to develop these models in the absence of these data. Recently published Australian-specific GMPEs which employ these numerical techniques are now available and these will be integrated into GA's future hazard outputs. This paper addresses several fundamental aspects related to ground-motion in Australia that are necessary to consider in the update of the National Earthquake Hazard Map, including: 1) a summary of recent advances of ground-motion modelling in Australia; 2) a comparison of Australian GMPEs against those commonly used in other stable continental regions; 3) a comparison of new GMPEs against their intensity-based counterparts used in the previous hazard map; and 4) the impact of updated attenuation factors on local magnitudes in southeastern Australia. Specific regional and temporal aspects of magnitude calculation techniques across Australia and its affects on the earthquake catalogue will also be addressed.

A study of the consistency of gust wind speed records from two types of recording instruments has been undertaken. The study examined the Bureau of Meteorology's (BoM) wind speed records in order to establish the existence of bias between coincident records obtained by the old pressure-tube Dines anemometers and the records obtained by the new cup anemometers. This study was an important step towards assessing the quality and consistency of gust wind speed records that form the basis of the Australian Standards/NZ Standards for design of buildings for wind actions (AS/NZS 1170.2:2011 and AS 4055:2006). The Building Code of Australia (BCA) requires that buildings in Australia meet the specifications described in the two standards. BoM has been recording peak gust wind speed observations in the Australian region for over 70 years. The Australia/New Zealand Wind Actions Standard as well as the wind engineering community in general rely on these peak gust wind speed observations to determine wind loads on buildings and infrastructure. In the mid-1980s BoM commenced a program to replace the aging Dines anemometers with Synchrotac and Almos cup anemometers. During the anemometer replacement procedure, many localities had both types of anemometers recording extreme events. This allowed us to compare severe wind recordings of both instruments to assess the consistency of the recordings. The results show that the Dines anemometer measures higher gust wind speeds than the 3-cup anemometer when the same wind gust is considered. The bias varies with the wind speed and ranges from 5 to 17%. This poster presents the methodology and main outcomes from the assessment of coincident measurements of gust wind speed.

The tectonic origin, paleoearthquake histories and slip rates of six normal faults (referred to here as the Rahotu, Oaonui, Kina, Kiri, Ihaia and Pihama faults) have been examined for up to ~26 kyr within the Taranaki Rift, New Zealand. A minimum of 13 ground-surface rupturing paleoearthquakes have been recognised on four of the faults using analysis of displaced late Quaternary stratigraphy and landforms. These data, in combination with 21 new radiocarbon dates, constrain the timing, slip and magnitude of each earthquake. The faults have low throw rates (~0.1-0.8 mm/yr) and appear to be buried near the Mt Taranaki volcanic cone. Recurrence intervals between earthquakes on individual faults typically range from 3-10 kyr (average ~ 6 kyr), with slip/earthquake ranging from ~0.3-1.5 m (average ~0.7 m). Recurrence intervals and slip/earthquake typically vary by up to a factor of three on individual faults, with only the Oaonui Fault displaying near-characteristic slip (of about 0.5 m) during successive earthquakes. The timing and slip of earthquakes on individual faults appear to have been interdependent, with each event possibly relieving stress and decreasing the likelihood of additional earthquakes across the system. Earthquake magnitudes are estimated to be M 6.5-6.7. The dating resolution of paleoearthquakes is generally ±1-2 kyr and is presently too imprecise to test the temporal relations between seismic events and either volcanic eruptions or lahars formed by debris avalanches during cone collapse. It is unlikely, however, that formation of the ~7.8 kyr Opua Formation lahar was triggered by a large earthquake on the Rahotu, Oaonui or Kina faults which, of the faults studied, are farthest from the Mt Taranaki volcanic cone.

Geoscience Australia has developed a model to assess severe wind hazard for large-scale numerical model-derived grided data. The severe wind modelling approach integrates two models developed at Geoscience Australia: a) A statistical model based on observations which determines return periods (RP) of severe winds using Extreme Value distributions (EVD), and b) A model which extracts mean wind speeds from high resolution numerical models (climate simulations) and generates wind gust from the mean speeds using Monte Carlo simulation (convolution with empirical gust factors) This methodology is particularly suitable for the study of wind hazard over large regions, and is being developed to provide improved spatial information for the Australia/NZ Wind Loading Standard (AS/NZS 1170.2, 2002). The methodology also allows comparison of current and future wind hazard under changing climate conditions. To illustrate the characteristics and capabilities of the methodology, the determination of severe wind hazard for a high-resolution grid encompassing the state of Tasmania (south of the Australian continent) will be presented and discussed, considering both the current and a range of possible future climate conditions (utilising IPCC B1 & A2 emission scenarios).

Victorian 2009 Bushfire Research Response Final Report October 2009

No abstract available

Cliff Head is the only producing oil field in the offshore Perth Basin. The lack of other exploration success has lead to a perception that the primary source rock onshore (Triassic Kockatea Shale) is absent or has limited generative potential. However, recent offshore well studies show the unit is present and oil prone. Multiple palaeo-oil columns were identified within Permian reservoir below the Kockatea Shale regional seal. This prompted a trap integrity study into fault reactivation as a critical risk for hydrocarbon preservation. Breach of accumulations could be attributed to mid Jurassic extension, Valanginian breakup, margin tilt or Miocene structuring. The study focused on four prospects, covered by 3D seismic data, containing breached and preserved oil columns. 3D geomechanical modelling simulated the response of trap-bounding faults and fluid flow to mid Jurassic-Early Cretaceous NW-SE extension. Calibration of modelling results against fluid inclusion data, as well as current and palaeo-oil columns, demonstrates that along-fault fluid flow correlates with areas of high shear and volumetric strains. Localisation of deformation leads to both an increase in structural permeability promoting fluid flow, and the development of hard-linkages between reactivated Permian reservoir faults and Jurassic faults producing top seal bypass. The main structural factors controlling the distribution of permeable fault segments are: (i) failure for fault strikes 350??110?N; (ii) fault plane intersections generating high shear deformation and dilation; and (iii) preferential reactivation of larger faults shielding neighbouring structures. These results point to a regional predictive approach for assessing trap integrity in the offshore Perth Basin.

The tectonic setting of Australia has much in common with North America east of the Rocky Mountains because stable continental crust makes up the whole continent. The seismicity is still sufficient to have caused several damaging earthquakes in the past 50 yr. However, uncertainties in the earthquake catalogue limit the reliability of hazard models. To complement traditional hazard estimation methods, alternative methods such as paleoseismic, geodynamic numerical models and high-resolution global positioning system (GPS) are being investigated. Smoothed seismicity analysis shows that seismic recurrence varies widely across Australia. Despite the limitations of the catalogue, comparisons of regional strain rates calculated from the seismicity are consistent with data derived from geodetic techniques. Recent paleoseismic studies, particularly those examining high-resolution digital elevation models, have identified many potential prehistoric fault scarps. Detailed investigation of a few of these scarps suggests that the locus of strain release is migratory on a time scale an order of magnitude greater than the instrumental seismic catalogue, consistent with Australia's low-relief landscape. Numerical models based on the properties of the Australian plate provide alternative constraints on long-term crustal deformation. Two attenuation models for Australia have recently been developed. Because Australiais an old, deeply weathered continent that has experienced little Holocene glaciation, it has very little material comparable to North American "hard rock" site classification. The combination of relatively low attenuation crust under widespread thick weathered regolith makes the use of ground-motion and site response models derived from Australian data vital for Australian hazard assessment. Risk modeling has been used to assess sensitivities associated with variations in both source and ground-motion models. Systematic analyses allow the uncertainty in these models to be quantifi ed. Uncertainty in most input models contributes a 30%-50% variation in the predicted loss. Where a city lies in a thick sedimentary basin, such as Perth, uncertainties in the behavior of the basin can result in a 500% variation in predicted loss.