Legacy product - no abstract available

Legacy product - no abstract available

Legacy product - no abstract available

Legacy product - no abstract available

Legacy product - no abstract available

Legacy product - no abstract available

No product available. Removed from website 25/01/2019

Stochastic finite-fault ground-motion prediction equations (GMPEs) are developed for the stable continental region of southeastern Australia (SEA). The models are applicable for horizontal-component ground motions for earthquakes 4.0 <= MW <= 7.5 and distances less than 400 km. The models are calibrated with updated source and attenuation parameters derived from SEA ground-motion data. Careful analysis of well-constrained earthquake stress parameters indicates a dependence on hypocentral depth. It is speculated that this is the effect of an increasing crustal stress profile with depth. However, rather than a continuous increase, the change in stress parameter appears to indicate a discrete step near 10 km depth. Average stress parameters for SEA earthquakes shallower and deeper than 10 km are estimated to be 23 MPa and 50 MPa, respectively. These stress parameters are consequently input into the stochastic ground-motion simulations for the development of two discrete GMPEs for shallow and deep events. The GMPEs developed estimate response spectral accelerations comparable to the Atkinson and Boore (BSSA, 2006) GMPE for eastern North America (ENA) at short rupture distances (less than approximately 100 km). However, owing to higher attenuation observed in the SEA crust (Allen and Atkinson, BSSA, 2007), the SEA GMPEs estimate lower ground-motions than ENA models at larger distances. The response spectral models are validated against moderate-magnitude 4.0 <= MW <= 5.3 earthquakes from eastern Australia. Overall the SEA GMPEs show low median residuals across the full range of period and distance. In contrast, Eastern North American models tend to overestimate response spectra at larger distances. Because of these differences, the present analysis justifies the need to develop Australian-specific GMPEs where ground-motion hazard from a distant seismic source may become important.

Legacy product - no abstract available

In Global ShakeMap (GSM) applications where access to real-time ground-motion data - which constrains the shaking - is often limited, we must rapidly estimate the shaking distribution in the earthquake source region using solely predictive techniques. Current ShakeMap practice is to first calculate instrumental ground motions using a Ground-Motion Prediction Equation (GMPE). These instrumental ground motions are subsequently converted to macroseismic intensities, which are employed to evaluate human exposure to potentially fatal levels of ground-shaking in PAGER (Prompt Assessment of Global Earthquakes for Response). Here, we use the combined dataset of global instrumental and macroseismic intensity ground motion data gathered for the Atlas of ShakeMaps (Allen et al., this meeting) for evaluating the GSM approach. Several commonly used GMPEs are evaluated for active tectonic crust, subduction zones, and stable continental regions. Using our preferred instrumental GMPE, we subsequently evaluate peak motion to intensity conversion equations. Finally, we evaluate several intensity prediction equations against the ShakeMap Atlas dataset. This review has led us to recommend several fundamental changes to current GSM practice, particularly in the prediction of active crustal ground motions. We also recommend that macroseismic intensities should be predicted using conversion equations that consider earthquake magnitude and distance to rupture, in addition to peak ground motions. Though not exhaustive, this review provides a comprehensive analysis of GMPEs and macroseismic intensity prediction techniques in different tectonic regimes against a large dataset of global ground motion data. The primary purpose of this study is to evaluate these techniques with a view of improving current practices in rapid ground motion prediction for the GSM and PAGER systems.