Mapping shallow faults at the Evrona playa site using high‐resolution reflection method

Abstract

A shallow high‐resolution seismic reflection survey was carried out at the Evrona playa site in the southern Arava valley, Israel. The aim of the survey was to detect and map faults in the shallow subsurface (upper 100–150 m) and establish the relationship of the morphological features revealed by aerial photographs and surface geological mapping with the faults detected in the subsurface. The survey included three seismic lines shot using the P-wave technique and one SH-wave line, which overlapped one of the P-wave lines. The seismic energy source on all the lines was a sledge hammer. The acquired reflection data were of good quality and did not require special processing efforts. The seismic sections along the lines show a sequence of reflected events within the 8–150 m range. At several locations, continuity of the events is interrupted by a system of faults. These faults form flower structures apparently related to strike‐slip motions typical of the region. Comparison of the faults mapped on the seismic sections with those expressed by surface morphological features generally show good correspondence. The results of the seismic survey provide important information for the study of paleoseismicity and seismic hazards in the investigated area.