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The record of large earthquake occurrence in Australia's landscape provides an opportunity to better understand the long-term characteristics of stable continental region deformation, and an important tool to extend the historic earthquake catalogue to a time-frame meaningful to intraplate settings. In the last 5 years, interrogation of geological and geomorphological datasets, and consultation with earth scientists, has resulted in the identification of more than 200 fault scarps which are thought to have formed in the current Australian crustal stress regime. Only a handful of these have been quantitatively examined to determine seismic source parameters (e.g. timing of events, recurrence, magnitude). However, three important characteristics are revealed in the extant data:
1) recurrence of surface breaking earthquakes on an individual fault is typical (ie. active faults remain weak), 2) temporal clustering of events is apparent on many faults (ie. large earthquake recurrence in 'active' phases might be much less than during 'inactive' phases), and 3) significantly larger events than have been seen in historic times (MW>7.0) might be expected in the future, Australia-wide. These data have been combined with information such as the total displacement across faults in the current stress regime, fault length and distribution, and relationship of faults to contemporary seismicity, topography and landscape to assess the response of the Australian crust to the imposed stresses. The primary finding is that response is heterogeneous and Australia may be divided into a number of ?neotectonic' domains which are distinguished by differing active fault characteristics.
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