The seismic hazard of Australia – a venture into an uncertain future

The seismic hazard of Australia is one of the most difficult on the globe to characterise, due to intraplate tectonics with faults capable of producing Mw7.0 earthquakes in the vicinity of several major Australian cities like Adelaide or Perth, yet a recorded history of less than 250 years. The lack of long-term historical earthquake data makes it extremely difficult to sufficiently quantify return periods of large events in most locations. Although the majority of sources in Australia represent low to moderate seismicity characteristics, they are still capable of causing major damage in many Australian communities. Recent studies of the tectonic faulting mechanisms of Australia and new developments in handling uncertainties of low seismicity regions are used to develop detailed probabilistic hazard maps for Australia's major capital cities. In addition, characteristic earthquake scenarios are developed for various return periods for these locations. The assessment of uncertainties within the intraplate setup of Australia and the short earthquake record is taken into account when calculating the strong seismicity return periods. This study provides a detailed insight into the probabilistic and deterministic seismic hazard of Australia and its major cities for various time periods, especially for the consideration of risk modelling.