Recent microseismicity and normal fault activity in the Northeastern Oman Mountains, UAE

Recently available seismological data reveal NE trending microseismic activity clusters in parts of the Oman Mountains, UAE. These data and focal mechanisms are combined with surface structural data to produce a simple neotectonic model to explain the seismicity of the terrain between Fujairah and Dibba. In this area there is a series of NE-SW to N-S trending faults limited in their southwestern extension by the NW trending Wadi Ham Fault (WHF). The faults show slip histories indicating multiple use during the Cretaceous and Tertiary-recent tectonic events. Since the late Tertiary these faults have dominantly normal slip histories. They provide a tensional release mechanism for stress build-ups on the N-S Zendan Fault, which separates the Makran subduction zone from the Zagros continent-continent (Alpine) zone. The Fujairah-Dibba section is modelled as a dilatational zone associated with the southern termination of the N-S trending Zendan Fault. One consequence of this model is that the previously reported dextral and sinistral slip on the WHF may not indicate significant changes in regional principal stress orientations.