The cost of landslide is underestimated in Australia because their impact and loss are not readily reported or captured. There is no reliable source of data which highlights landslide cost to communities and explains who currently pays for the hazard and how much costs are. The aim of this document is to investigate and analyse landslide costs within a Local Government Area (LGA) in order to highlight the varied landslide associated costs met by the local government, state traffic and rail authorities and the public. It is anticipated this may assist in developing a baseline awareness of the range of landslide costs that are experienced at a local level in Australia. Initial estimates in this study indicate that cumulative costs associated with some landslide sites are well beyond the budget capacity of a local government to manage. Furthermore, unplanned remediation works can significantly disrupt the budget for planned mitigation works over a number of years. Landslide costs also continue to be absorbed directly by individual property owners as well as by infrastructure authorities and local governments. This is a marked distinction from how disaster costs which arise from other natural hazard events, such as flood, bushfire, cyclone and earthquake are absorbed at a local level. It was found that many generic natural hazard cost models are inappropriate for determining landslide costs because of the differences in the types of landslide movement and damage. Further work is recommended to develop a cost data model suitable for capturing consistent landslide cost data. Better quantification of landslide cost is essential to allow for comparisons to be made with other natural hazard events at appropriate levels. This may allow for more informed policy development and decision making across all levels.

One of the important inputs to a probabilistic seismic hazard assessment is the expected rate at which earthquakes within the study region. The rate of earthquakes is a function of the rate at which the crust is being deformed, mostly by tectonic stresses. This paper will present two contrasting methods of estimating the strain rate at the scale of the Australian continent. The first method is based on statistically analysing the recently updated national earthquake catalogue, while the second uses a geodynamic model of the Australian plate and the forces that act upon it. For the first method, we show a couple of examples of the strain rates predicted across Australia using different statistical techniques. However no matter what method is used, the measurable seismic strain rates are typically in the range of 10-16s-1 to around 10-18s-1 depending on location. By contrast, the geodynamic model predicts a much more uniform strain rate of around 10-17s-1 across the continent. The level of uniformity of the true distribution of long term strain rate in Australia is likely to be somewhere between these two extremes. Neither estimate is consistent with the Australian plate being completely rigid and free from internal deformation (i.e. a strain rate of exactly zero). This paper will also give an overview of how this kind of work affects the national earthquake hazard map and how future high precision geodetic estimates of strain rate should help to reduce the uncertainty in this important parameter for probabilistic seismic hazard assessments.

The Australian continent is actively deforming at a range of scales in response to far-field stresses associated with plate margins, and buoyancy forces associated with mantle dynamics. On the smallest scale (101 km), fault-related deformation associated with far-field stress partitioning has modified surface topography at rates of up to ~100 m / Myr. This deformation is evidenced in the record of historical earthquakes, and in the pre-historic record in the landscape. Paleoseismological studies indicate that few places in Australia have experienced a maximum magnitude earthquake since European settlement, and that faults in most areas are capable of hosting potentially catastrophic earthquakes with magnitudes in excess of 7.0. New South Wales is well represented in terms of its pre-historic earthquake record. Seismogenic faulting in the last 5-10 million years is thought to be responsible for locally generating up to 200 m of the contemporary topographic relief of the Eastern Highlands. Faults west of Sydney belonging to the Lapstone Structural Complex, and faults beneath the greater Sydney region, have been demonstrated to be associated with infrequent damaging earthquakes. . Decisions relating to the siting and construction of the built environment should therefore be informed with knowledge of the local neotectonics.

Faults of the Lapstone Structural Complex (LSC) underlie 100 km, and perhaps as much as 160 km, of the eastern range front of the Blue Mountains, west of Sydney. More than a dozen major faults and monoclinal flexures have been mapped along its extent. The Lapstone Monocline is the most prominent of the flexures, and accounts for more than three quarters of the deformation across the complex at its northern end. Opinion varies as to whether recent tectonism, or erosional exhumation of a pre-existing structure, better accounts for the deeply dissected Blue Mountains plateau that we see today. Geomorphic features such as the abandoned meanders at Thirlmere Lakes illustrate the antiquity of the landscape and favour an erosional exhumation model. According to this model, over-steepened reaches developed in easterly flowing streams at the Lapstone Monocline when down-cutting through shale reached more resistant sandstone on the western side of the LSC. These over-steepened reaches drove headward (westerly) knick point retreat, ultimately dissecting the plateau. However, a series of swamps and lakes occurring where small easterly flowing streams cross the westernmost faults of the LSC, coupled with over-steepened reaches 'pinned' to the fault zones in nearby larger streams, imply that tectonism plays a continuing role in the development of this landscape. We present preliminary results from an ongoing investigation of Mountain Lagoon, a small fault-bound basin bordering the Kurrajong Fault in the northern part of the LSC.

Geoscience Australia (GA) was engaged by Sydney Water Corporation (SW) to review existing geological, geophysical and geotechnical data from the Sydney region in an effort to better understand seismic hazard in SW's area of operations. The main motivation is that this information can be used to improve SW's understanding of the level of earthquake risk to their infrastructure in order to support their asset management practices. Of particular interest is improving SW's understanding of asset damage or loss and potential network disruption following a large earthquake. One of the main factors influencing earthquake hazard in the Sydney Water area of operations is the likelihood of a large earthquake to the west of Sydney on what is known as the Lapstone Structural Complex. Research conducted by Geoscience Australia suggests that large earthquakes in the Lapstone Structural Complex are extremely rare (i.e. they may only happen once every few million years). This means that the area probably does not contribute as much to the seismic hazard in Sydney as has been previously thought. An equally important factor is the response of near-surface geological materials to earthquake shaking. Two seismic site classification maps for the Sydney region have been developed here to characterise materials in terms of their potential response. One uses the modified United States National Earthquake Hazard Reduction Program (NEHRP) classification scheme, while the other uses the Australian Earthquake Loading Standard (AS1170.4-2007) classification scheme. Assessment and validation of the classifications against independently acquired data from sub-surface investigations in the region suggest that both classifications provide a satisfactory representation of the distribution of materials and their potential to amplify earthquake energy. The exception to this outcome is the area underlain by the Botany Basin, where geophysical investigations and drilling data have identified the thicker basin fill sediments as having the potential to effectively increase earthquake hazard. The aforementioned AS1170.4 site classification was used to generate Australian Standard (AS1170.4-2007) earthquake hazard maps covering SW's area of operations. The analyses were completed for three spectral periods (0 s, 0.2 s and 1.0 s) and two return periods (500 years and 800 years). Results show that earthquake shaking at 0.2 s spectral period produced the highest hazard at both return periods. Overall, areas characterised by the presence of unconsolidated Cenozoic sedimentary units exhibited the highest earthquake hazard under all conditions. The modified NEHRP site classification outputs were used to produce a probabilistic seismic hazard assessment for the SW area of operations, using the same spectral periods and return periods. Comparison of the AS1170.4-2007 and EQRM outputs reveal several key findings. Firstly, the use of the modified NEHRP site classification scheme better differentiates the properties of geological materials, and therefore the seismic hazard, across the SW area of operations. Secondly, the probabilistic seismic hazard assessment produced values that were up to 6 times lower than those generated using the Australian Standard methodology. Lastly, regardless of the site classification schema or hazard methodology employed, areas characterised by relatively unconsolidated Cenozoic (predominantly Quaternary) sedimentary deposits always represented the highest levels of earthquake hazard.

This paper discusses two of the key inputs used to produce the draft National Earthquake Hazard Map for Australia: 1) the earthquake catalogue and 2) the ground-motion prediction equations (GMPEs). The composite catalogue used draws upon information from three key catalogues for Australian and regional earthquakes; a catalogue of Australian earthquakes provided by Gary Gibson, Geoscience Australia's QUAKES, and the International Seismological Centre. A complex logic is then applied to select preferred location and magnitude of earthquakes depending on spatial and temporal criteria. Because disparate local magnitude equations were used through time, we performed first order magnitude corrections to standardise magnitude estimates to be consistent with the attenuation of contemporary local magnitude ML formulae. Whilst most earthquake magnitudes do not change significantly, our methodology can result in reductions of up to one local magnitude unit in certain cases. Subsequent ML-MW (moment magnitude) corrections were applied. The catalogue was declustered using a magnitude dependent spatio-temporal filter. Previously identified blasts were removed and a time-of-day filter was developed to further deblast the catalogue.

Did you know that landslides kill more people in Australia than earthquakes. Using these activities, encourage your students to understand landslide hazards and how to reduce their own risks. This education resource consists of: - 44 page booklet - 11 reproducible activitities - suggested answers Please note: this booklet does not contain teacher notes. Suitable for secondary levels 7-12

The inventory of over 200 fault scarps captured in GA's Australian neotectonics database, when grouped according to the spatial divisions prescribed in the recently published neotectonics domain model, allows for estimates of maximum magnitude earthquake (Mmax) to be calculated across the SCR crust of Australia. The 75th percentile value of fault scarp length for all features within a given domain was used in calculations using the average of a range of published relations. Results range between Mw 7.0 - 7.5 ± 0.2 magnitude units (Table 1), demonstrating that potentially catastrophic earthquakes are possible Australia-wide. These data form the basis for future seismic hazard assessments, including those for building design codes, both in Australia and analogous SCRs worldwide.

A statistical downscaling approach is used to compare changes in environmental indicators of tropical cyclone characteristics between three greenhouse gas emissions scenarios in the Australian region, using results from models used for the IPCC 4th Assessment Report. Maximum potential intensity is shown to change linearly with global mean temperature, independent of emissions scenario, with a 2-3% increase per degree of global warming in Australia's tropical regions. Changes in vertical wind shear are more ambiguous, however the magnitude of changes in tropical cyclone genesis regions is small. The genesis potential index increases significantly in all scenarios, and appears to be driven by the increase in MPI. Results for Australia's tropical regions suggest that tropical cyclone intensity is highly likely to increase with global warming, while results for frequency are suggestive of a frequency increase, but less conclusive. Further work to assess frequency changes will allow quantification of changes in tropical cyclone hazard under climate change.

The recently released ISC-GEM catalogue was a joint product of the International Seismological Center (ISC) and the Global Earthquake Model (GEM). In a major undertaking it collated, from a very wide range of sources, the surface and body wave amplitude-period pairs from the pre digital era; digital MS, mb and Mw; collated Mw values for 970 earthquakes not included in the Global CMT catalogue; used these values to determine new non-linear regression relationship between MS and Mw and mb and Mw. They also collated arrival picks, from a very wide range of sources, and used these to recompute the location, initially using the EHB location algorithm then revised using the ISC location algorithm (which primarily refined the depth). The resulting catalogues consists of 18871 events that have been relocated and assigned a direct or indirect estimate of Mw. Its completeness periods are, Ms - 7.5 since 1900, Ms - 6.25 1918 and Ms - 5.5 1960. This catalogue assigns, for the first time, an Mw estimate for several Australian earthquakes. For example the 1968 Meckering earthquake the original ML, mb and MS were 6.9, 6.1 and 6.8, with empirical estimates of Mw being 6.7 or 6.8. The ISC-GEM catalogue assigns an Mw of 6.5. We will present a poster of the Australian events in this ISC_GEM catalogue showing, where available, the original ML, mb, Ms, the recalculated mb and Ms, and the assigned Mw. We will discuss the implications of this work for significant Australian earthquakes.