Geophysical study of a palaeofualt scarp near Hyden, Western Australia

Abstract

Fault scarps created by prehistoric seismic events are potentially important source of information for seismic-hazard assessment. Establishing the type of faulting responsible for the scarp and its structural setting allows other earthquake prone areas to be identified. Dating the scarp, along with estimates of the magnitude of the event responsible for its formation based on accurate mapping of the structure, allow recurrence intervals to be estimated. Aeromagnetic data flown over a fault scarp at Hyden allow the geological structures reactivated in the scarp-forming events to be identified. At Hyden thrust faulting occurred on a pre-existing structure, one of several similar structures in the area. A GPR survey allows sedimentary materials deposited adjacent to the scarp to be located in the subsurface. Dating of these materials will allow the age of the scarp-forming event to be established.