Oligocene/Early Miocene E/W-Shortening in the Oman Mountains Related to Oblique Arabia-India Convergence

Field survey, literature review, geological map interpretation, GPlates reconstruction and LA-ICP-MS U-Pb dating of synkinematic calcite demonstrate that ∼E/W-shortening in eastern Oman was significant and related to oblique convergence of Arabia and India from 32.5 to 20 Ma. Approximately N/S-striking contractional structures, WNW to NNW-striking sinistral faults and ∼E/W-striking normal faults characterize a ∼250 km × ∼50 km wrench corridor in the eastern Oman Mountains (Hajar Wrench Corridor, HWC). Numerous faults/folds indicate that deformation of the HWC is widely distributed but concentrated along WNW to NNW-striking major faults at the SW margin of the Saih Hatat Dome, forming the Hajar Shear Zone, which reactivated basement faults. GPlates reconstructions reveal that N-drifting India rotated 8° counter-clockwise with respect to fixed Arabia from 32.5 to 20 Ma, leading to a minimum of 100 km E/W convergence between both plates. This convergence created the sinistral HWC with a displacement of a few to several tens of kilometers. Independently from the GPlates time constraints, two U-Pb ages of synkinematic calcites, crystallized along faults during HWC movement, yield compatible ages of 30.08 ± 0.47 and 22.31 ± 2.15 Ma (2 standard error). E/W-shortening also affected the northern Oman Mountains, creating the ∼N/S-striking Hagab Thrust in the Musandam Peninsula and the Jabal Hafit Anticline.