Fault geometry and slip rates from the Nullarbor and Roe Plains of south-central Australia: Insights into the spatial and temporal characteristics of intraplate seismicity

Abstract

Analysis of TanDEM-X and Shuttle Radar Topography Mission (SRTM) data reveals geomorphic evidence for 292 fault-propagation fold scarps across the Miocene Nullarbor and Pliocene Roe Plains in south-central Australia. Vertical displacements (VD) are determined using topographic profiling of a subset (n = 48) of the fold traces. Fault dips (mean = 44 +16/−14° at 1σ) are estimated from seismic reflection data; the mean dip is assigned to faults with unknown dip and combined with VD to estimate net displacements (ND) and average net displacements (AD) for each fault. AD exceeds single-event displacements estimated from fault-length scaling regressions, indicating the identified faults have hoste..