Exceptional Scarp Preservation in SW Namibia Reveals Geological Controls on Large Magnitude Intraplate Seismicity in Southern Africa

Abstract Four previously unrecognized neotectonic fault scarps in southwest Namibia are described. These relatively straight, simple but segmented structures 16–80 km long and have measured vertical separations of 0.7–10.2 m. We estimate that each is capable producing earthquakes M w 6.4 or greater, indicating large may occur despite limited cumulative displacement. There strong evidence some these were formed by repeated earthquakes. Comparison with aeromagnetic geological maps reveal the normal faults reactivate major crustal weaknesses orientated north‐south northwest‐southeast perpendicular to local gravitational potential energy gradient. The presence an area a record instrumental seismicity suggests max this region be much larger than generally assumed. They highlight necessity incorporating information from studies into probabilistic seismic hazard assessments region, similar way other stable continental regions such as Australia. fact gone hitherto unrecorded significant further research needed characterize sources hazard. identification apparent cluster magnitude related exceptional preservation rather comparatively rapid deformation. If interpretation correct, then represent important indication across occurrence infrequent large‐magnitude on should considered throughout southwestern Africa.