A 3-D crustal shear wave velocity model and Moho map below the Semail Ophiolite, eastern Arabia

SUMMARY The Semail Ophiolite in eastern Arabia is the largest and best-exposed slice of oceanic lithosphere on land. Detailed knowledge tectonic evolution shallow crust, particular during after ophiolite obduction Late Cretaceous times contrasted by few constraints physical compositional properties middle lower continental crust below obducted units. role inherited, pre-obduction crustal architecture remains therefore unaccounted for our understanding present-day geology. Based seismological data acquired a 27-month campaign northern Oman, Ambient Seismic Noise Tomography Receiver Function analysis provide first time 3-D radially anisotropic shear wave velocity (VS) model consistent Moho map iconic Ophiolite. highlights deep boundaries that segment Arabian basement two distinct previously undescribed Western Jabal Akhdar Zone separates with typical thickness ∼40–45 km northwest from compositionally different terrane southeast interpreted as accreted Pan-African orogeny Neoproterozoic times. East Ibra Zone, another boundary, decreases to 30–35 very high VS suggest large-scale mafic intrusions into, possible underplating occurred most likely Permian breakup Pangea. Mafic reworking sharply bounded (upper crustal) Gap Fault which no such velocities are found crust. Topography Oman Mountains supported mild root depth highest topography, Dome, ∼42 km. Radial anisotropy robustly resolved upper aids discriminating dipping allochthonous units autochthonous sedimentary rocks indistinguishable isotropic alone. Lateral variations highlight Haylayn Massif flank Dome Hawasina Window deepest reaching unit. ∼10 southern massifs, ≤5 elsewhere.