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. South Australia 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 generating more than 30-50% of the contemporary topographic relief separating the highlands of the Flinders and Mt Lofty Ranges from adjacent plains, and perhaps as much as a third of the strain budget of the entire continent is accommodated there. Adelaide itself straddles several faults which are arguably some Australia's most active. Decisions relating to the siting and construction of the built environment should therefore be informed with knowledge of the local neotectonics.

In plate boundary regions moderate to large earthquakes are often sufficiently frequent that robust estimates of fundamental seismic parameters such as the recurrence intervals of large earthquakes and maximum credible earthquake (Mmax) can be made. The same is not true for the Stable Continental Regions (SCRs) of the world. Large earthquakes are so infrequent that the data distributions upon which recurrence and Mmax estimates are based are heavily skewed towards magnitudes below Mw 5.0, and so require significant extrapolation up to magnitudes for which damaging ground-shaking might be expected. The rarity of validating evidence from palaeo-surface rupturing earthquakes limits the confidence with which extrapolated statistical parameters may be applied. Herein we present an earthquake catalogue containing, 150 palaeo-earthquakes, from 60 palaeo-earthquake features, based upon a >100 ka record of palaeo-earthquakes recorded in the Precambrian Shield of southwest Western Australia. From this data we show that Mmax for non-extended-SRC is well constrained at M7.22 and M7.65 for extended-SCR. In non-extended-SRC the earthquakes are likely episodic with periods of quiescence of 10-100ka in between active phases. The largest earthquakes are likely to occur on pre-existing faults. We expect these results might apply to most areas of non-extended-SCR worldwide.

The tau-p velocity imaging method, first developed for obtaining the velocity field from marine multichannel seismic data, has been applied to refracted waves from the regolith in regional seismic reflection surveys on land. The technique converts travel time picks from the refracted wavefield into two-dimensional velocity models, by transforming from time-offset into the tau-p domain. Each arrival is mapped individually, and the `true? velocity and position of the ray turning point is obtained by considering reversed raypaths. Thus the data are transformed directly into a depth or two-way-time image of the subsurface displayed in seismic velocity. The method is extremely fast and involves no interpretive steps or iteration. Ideal datasets contain the refracted wavefield sampled densely and equally in the shot and receiver domains. It was therefore decided to test the application of the method for mapping the velocity structure of a portion of regolith, and to compare the results with those obtained using more conventional methods. The area chosen for study was part of a regional seismic reflection line across the Lachlan River palaeo-valley in central NSW. The data set consisted of the first break picks for 240 channel records with receivers spaced every 40 m and vibe points every 40 m. The velocity images were produced as both time and depth sections and compared with the refractor model based on a one layer solution by the reciprocal method. A low velocity region on the image corresponds to the deepest part of the refractor model, interpreted as the thickest part of the palaeo-valley. Bedrock velocity variations are also mapped but appear more clearly in the refractor velocity profile. While further tuning may be required for land work, the technique has the advantage that velocities can be directly imaged and potentially related to regolith physical properties.

In hard rock regions, a large range of stacking velocities is required to correctly stack reflectors of different dips. Typically, horizontal reflectors stack at 6000 m/s, whereas reflectors with dips of 60 degrees stack at 12,000 m/s. For high fold (vibrator) data, correct stack of conflicting dips can be achieved by dip moveout (DMO) correction. However, for lower fold (dynamite) data, the sparse offset distribution complicates application of DMO. An alternative technique involves producing stacks with different stacking velocities and stacking these stacks. This technique was applied to two seismic reflection data sets, low fold dynamite from Broken Hill and high fold vibrator data from the Lachlan Fold Belt. The Lachlan data set was used as both full 60/120 fold and reduced 10/20 fold. Velocity analysis, both analytical and empirical, was carried out to determine the range of stacking velocities. Stacking velocity increases with dip angle (cos-1 theta), but the velocity range across which an event stacks coherently increases more rapidly (approximately cos-3 theta for velocities typical of hard rock)). The most critical area for analysis is the first two seconds of data, due to greater sensitivity of NMO to stacking velocity. The optimum number of stacks is an important consideration, based on the number of stacks in which an event contributes coherently to the sum The Broken Hill stack data showed simultaneous imaging of horizontal and dipping events. For the Lachlan reduced fold data set, horizontal and moderate to steeply dipping events were stacked successfully, although not as well as the post-DMO stack of the full fold data. The technique has some problems at the shallowest levels, where the stack can be degraded due to time shifts of events in the individual stacks.

One's understanding of the crustal architecture of Australia's Archaean Yilgarn Craton has increased greatly over the last few years with the collection a range of different seismic data types. The seismic data collected range from broadband seismic studies using distant earthquakes to study lithospheric scale problems, receiver function studies to obtain crustal velocity variations, deep seismic reflection transects to image province to mine scale studies on specific structural problems within the top few kilometres of the crust. At the craton scale, broadband deployments, recording P-wave, S-wave and surface wave variations, have been used to develop 3D velocity models of the craton. These velocity models allow researchers and the Yilgarn Craton mineral industry to understand the larger picture variations within the craton. An interesting feature of the data, easily identified in 3D, is the presence of a fast S-wave velocity anomaly (> 4.8 km.s-1) within the upper mantle. This anomaly is east-dipping and has a series of step-down offsets that coincide approximately with terrain boundaries. Receiver function results show significant variation in crustal and upper mantle velocities across the craton. The receiver function results for the depth to the Moho are consistent with the deep seismic reflection data; both show an increase in depth to the east. Refraction results have provided the framework for the construction of a 3D crustal architecture of the Eastern Yilgarn Craton that suggests the dominant geodynamic process involved the development of a foreland basin with its associated contractional folding and thrusting events. This contractional event were separated by equally important extension events, with the seismic reflection data suggesting that extensional movement on shear zones was more common that previously thought. The seismic reflection suggests that the dominant mineral systems operating involved fluid flow up along crustal-penetrating shear zones. These seismic data have proved invaluable in constraining the crustal geometry of the Yilgarn Craton and in developing three-dimensional models of the crust and upper mantle of the Yilgarn Craton, Australia. In all these data sets, ANSIR, the Australian National Seismic Imaging Facility, is acknowledged for its part in the provision of equipment and expertise and in the data collection phases of the work

The Australian Seismological Report 2008 provides a summary of earthquake activity for Australia for 2008. It also provides a summary of earthquakes of Magnitude 5+ in the Australian Region, as well as an summary of Magnitude 6+ earthquakes worldwide. It has dedicated state and territory earthquake information including: largest earthquakes in the year; largest earthquakes in the state; and tables detailing all earthquakes detected by Geoscience Australia during the year. There are also contributions from Gary Gibson and Environmental Systems and Services describing Seismic Networks and providing Earthquake locations.

No abstract available

Regional seismic reflection data in hard rock areas contains more shallow information than might first be supposed. Here I use a subset of the 2005 Tanami Seismic Survey data to show that near surface features can be defined, including paleochannels, Palaeozoic basins and structures within the Proterozoic basement. Successful imaging depends on correct determination of refraction statics, including identification of refractor branches, and use of a floating or intermediate datum during seismic reflection processing. Recognition of steep stacking velocity gradients associated with surface referenced processing aids velocity analysis and can further delineate areas of thicker regolith in palaeochannels. The first arrival refraction analysis can also be applied in more detail to estimating thickness of regolith and depth to economic basement in areas of sedimentary cover.

We have used data recorded by a temporary seismograph deployment to infer constraints on the state of crustal stress in the Flinders Ranges in south-central Australia. Previous stress estimates for the region have been poorly constrained due to the lack of large events and limited station coverage for focal mechanisms. New data allowed 65 events with 544 first motions to be used in a stress inversion to estimate the principal stress directions and stress ratio.While our initial inversion suggested that stress in the region was not homogeneous, we found that discarding data for events in the top 2km of the crust resulted in a well-constrained stress orientation that is consistent with the assumption of homogeneous stress throughout the Flinders Ranges. We speculate that the need to screen out shallow events may be due to the presence in the shallow crust of either: (1) small-scale velocity heterogeneity that would bias the ray parameter estimates, or (2) heterogeneity in the stress field itself, possibly due to the influence of the relatively pronounced topographic relief. The stress derived from earthquakes in the Flinders Ranges show an oblique reverse faulting stress regime, which contrasts with the pure thrust and pure strike slip regimes suggested by earlier studies. However, the roughly E-W direction of maximum horizontal compressive stress we obtain supports the conclusion of virtually all previous studies that the Flinders Ranges are undergoing E-W compression due to orogenic events at the boundaries of the Australian and Indian Plates.

In mid 2010 an Indonesian team of scientists and practicians published the new Indonesian probabilistic seismic hazard analysis (PSHA) map. The new PSHA map will replace the previous version from 2002. One of the major challenges in developing the new map is that data for many active fault zones in Indonesia is sparse and mapped only at the regional scale, thus the input fault parameters for the PSHA inheret unavoidably large uncertainties. Despite the fact that most Indonesian islands are teared by active faults, only Sumatra has been mapped in sufficient detail. In other areas, such as Java and Bali, the most populated and developed regions, many active faults are not well mapped and studied. These include the well known Cimandiri-Lembang fault in west Java and the Opak fault near Jogyakarta that released the destructive M6.3 Yogyakarta earthquake in 2006. This year we start a national program to systematically study major active faults in Indonesia. The study will include the acquisition of high-resolution topography and images required for detailed fault mapping, measuring geological sliprates and locating good sites for paleoseismological studies. We will also conduct GPS-campaign surveys to measure geodetic sliprates. To study submarine active faults, we will collect and incorporate bathymetry and marine geophysical data. The research will be carried out, in part, through masters and Ph.D student thesis in the new graduate study program and research center, called GREAT - CrATER (Graduate Research for Earthquake and Active Tectonics and Center for Active Tectonics and Earthquake Research), hosted by LIPI and ITB, in partnership with the Australia-Indonesia Facility for Disaster Reduction (AIFDR). In the first four years of the program we will select several sites for active fault studies, particulary faults that pose the greatest risk to society.