Results from an audit of 32 petroleum exploration wells in the Bass Basin have shown that approximately half of the wells in the basin were invalid tests due to off-structure drilling or mis-interpretation. Of the remaining wells, primary reasons for failure were lack of effective seal, timing, trap validity, lack of access to mature source rocks or reservoir problems. In parts of the basin the regional seal (Demons Bluff Shale) has undergone a period of structural inversion during the late Tertiary resulting in seal breach. Anticlinal closures of Eocene age were particularly affected, while structures located on fault-bounded basement highs were less affected, and provide the only fields within the basin. In the Yolla and White Ibis fields, access to mature source rocks was provided by large-displacement, non-sealing faults, that linked the upper EVG reservoirs with deeper source rocks. Traps without this conduit have as yet been unsuccessful. Sandy units within the Eastern View Group in the Pelican Trough are tight reservoirs that have good porosity but poor permeability. This is due to diagenetic effects that prohibited the creation of secondary porosity and permeability. Although identified risks within the basin can be minimised, the key to successful exploration will be finding traps that were in-place prior to the generation of hydrocarbons, but did not undergo significant Tertiary inversion.

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.

Climate change is expected to increase severe wind hazard in many regions of the Australian continent with consequences for exposed infrastructure and human populations. The objective of this paper is to provide an initial nationally consistent assessment of wind risk under current climate, utilizing the Australian/New Zealand wind loading standard (AS/NZS 1170.2, 2002) as a measure of the hazard. This work is part of the National Wind Risk Assessment (NWRA), which is a collaboration between the Australian Federal Government (Department of Climate Change and Energy Efficiency) and Geoscience Australia. It is aimed at highlighting regions of the Australian continent where there is high wind risk to residential structures under current climate, and where, if hazard increases under climate change, there will be a greater need for adaptation. This assessment is being undertaken by separately considering wind hazard, infrastructure exposure and the wind vulnerability of residential buildings. The NWRA will provide a benchmark measure of wind risk nationally (current climate), underpinned by the National Exposure Information System (NEXIS; developed by Geoscience Australia) and the wind loading standard. The methodology which determines the direct impact of severe wind on Australian communities involves the parallel development of the understanding of wind hazard, residential building exposure and the wind vulnerability of residential structures. We provide the current climate wind risk, expressed as annualized loss, based on the wind loading standard.

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 Australian National Coastal Vulnerability Assessment (NCVA) was commissioned by the Federal Government to assess the risk to coastal communities from climate related hazards. In addition to an understanding of the impact/risk posed by the current climate, the study also examined the change in risk under a range of future climate scenarios. This assessment will provide information for application to policy decisions for, inter alia, land use, building codes, emergency management and insurance applications. Geoscience Australia coordinated the work undertaken to quantify the impact on property and infrastructure. This included the development of SMARTLINE, a nationally-consistent database of coastal morphology for the entire country, which provides critical information on the geology and landforms and their potential susceptibility to instability or degradation due to environmental or climatic factors. In a first-order attempt to assess the climate-change induced hazard to the coastal landscape, SMARTLINE data have been combined with sea-level rise (SLR) projections for 2030 and 2100, and 1 in 100 year current-climate storm surge estimates to determine potential areas of inundation and zones of instability where coastal recession due to SLR is predicted. Additionally, cyclonic wind hazard along Australia's northern coastline has been estimated using Geoscience Australia's Tropical Cyclone Risk Model, utilising synthetic tropical cyclone event sets derived from IPCC AR4 global climate models. The hazard levels have been modified for terrain, topographic and shielding effects to reflect localised variations in wind hazard.

Global climate change is putting Australia's infrastructure and in particular coastal infrastructure at risk. More than 80% of Australians live within the coastal zone. Almost 800,000 residences are within 3km of the coast and less than 6m above sea level. Much of Australia's land transport is built around road and rail infrastructure which is within the threatened coastal zone. A significant number of Australia's ports, harbours and airports are under threat. Australia's coastal zone contains several major cities, and supports agriculture, fisheries, tourism, coastal wetlands and estuaries, mangroves and other coastal vegetation, coral reefs, heritage areas and threatened species or habitats. Sea level rise is one physical effect of rising sea temperatures and is estimated at about 0.146m for 2030 (IPCC 2007) and up to 1.1m for 2100 (Antarctic and Climate Ecosystems CRC). The warming is likely to result in increases in intensity of both extra-tropical and tropical storms (spatially dependent) which are predicted to increase storm surge and severe wind hazard. Beaches, estuaries, coastal wetlands, and reefs which have adapted naturally to past changes in climate (storminess) and sea level over long time scales, now are likely to face faster rates of change. In many cases landward migration may be blocked by human land uses and infrastructure. Adaptation options include integrated coastal zone assessments and management; redesign, rebuilding, or relocation of capital assets; protection of beaches, dunes and maritime infrastructure; development zone control; and retreat plans.

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.

The term "Smartline" refers to a GIS line map format which can allow rapid capture of diverse coastal data into a single consistently classified map, which in turn can be readily analysed for many purposes. This format has been used to create a detailed nationally-consistent coastal geomorphic map of Australia, which is currently being used for the National Coastal Vulnerability Assessment (NCVA) as part of the underpinning information for understanding the vulnerability to sea level rise and other climate change influenced hazards such as storm surge. The utility of the Smartline format results from application of a number of key principles. A hierarchical form- and fabric-based (rather than morpho-dynamic) geomorphic classification is used to classify coastal landforms in shore-parallel tidal zones relating to but not necessarily co-incident with the GIS line itself. Together with the use of broad but geomorphically-meaningful classes, this allows Smartline to readily import coastal data from a diversity of differently-classified prior sources into one consistent map. The resulting map can be as spatially detailed as the available data sources allow, and can be used in at least two key ways: Firstly, Smartline can work as a source of consistently classified information which has been distilled out of a diversity of data sources and presented in a simple format from which required information can be rapidly extracted using queries. Given the practical difficulty many coastal planners and managers face in accessing and using the vast amount of primary coastal data now available in Australia, Smartline can provide the means to assimilate and synthesise all this data into more usable forms.

Geographical information systems (GIS) have been used to model building flood damage in South East Queensland. The research shows that if a flood with a 1% annual exceedence probability (AEP) occurred simultaneously in all rivers in the region, 47 000 properties would be inundated, with about half of the properties likely to experience overfloor flooding. 90% of affected properties are located in the Brisbane-Bremer River system and the Gold Coast catchment. 89% of properties affected by flooding are residential. Nearly 60% of the residential flood damage is located in the Brisbane-Bremer River system, with damage estimated to be highest in those areas which historically have suffered high flood losses. Equivalent average damage per residential building is highest in the Gold Coast catchment. If the cost of the actual damages were to be spread among all residential buildings in South East Queensland, than the equivalent flood damage would be 1.09% damage from a flood with a 1% AEP.

CSIRO climate change projections based on the IPCC Fourth Assessment Report indicate that Tasmania is one of the areas within the Australian region that will experience an increased magnitude of severe winds. This study utilises the Climate Futures for Tasmania (CERF project) fine scale climate projections which provide spatial detail of the increasing wind hazard derived through dynamic-downscaling utilizing a regional climate model forcing by 5 GCM's and two climate change scenarios (detailed by Sanabria and Cechet; this conference). These wind hazard estimates are used to determine the impact of the wind hazard on residential infrastructure in the Tasmanian region. Two regions of Tasmania were assessed, one in the north and one in the south. The risk assessment involves an understanding of exposure and wind vulnerability. Built environment exposure information was provided by the National EXposure Information System (NEXIS) developed by Geoscience Australia. Wind vulnerability relationships (relating gust wind speed to damage) were developed by Geoscience Australia through a series of expert workshops and the analysis of wind damage data. Return periods of exceedence loss levels were evaluated at buildings level across each region. These were subsequently used to evaluate annualised losses, which represent the average annual cost to the region of exposure to the wind hazard if viewed through a very wide window in time. Expressing the annualised loss as a percentage of the total reconstruction value gives a measure of the intensity of the risk to the studied community that is not as evident from simple dollar values. Risk projections for the Tasmanian region will be presented and the relationship between wind hazard and risk explored. These outputs will be crucial to informing climate change adaptation options regarding severe winds which should be of significant concern to planning, construction, emergency services and the community as a whole.