Pn-velocity structure beneath Arabia–Eurasia Zagros collision and Makran subduction zones
Published:January 01, 2014
Ali I. Al-Lazki, Khaled S. Al-Damegh, Salah Y. El-Hadidy, Abdolreza Ghods, Mohammad Tatar, 2014. "Pn-velocity structure beneath Arabia–Eurasia Zagros collision and Makran subduction zones", Tectonic Evolution of the Oman Mountains, H. R. Rollinson, M. P. Searle, I. A. Abbasi, A. I. Al-Lazki, M. H. Al Kindi
Download citation file:
We use Pn-tomography to map lithospheric mantle velocity and anisotropy at the Arabia–Eurasia plate boundary, namely Makran and Zagros. We use catalogue events recorded by Oman, UAE, Saudi Arabia and Iran networks, the International Seismological Centre and the National Earthquake Information Center. Events of 1.8–16 degree distances were used for this Pn-tomography. In this study we show that the northeastern Arabia plate is characterized by cold and stable lithospheric mantle. Contrastingly, Eurasia is underlain by hot unstable lithospheric mantle. The Arabia–Eurasia lithospheric suture follows the Zagros collision surface suture within c. 70 km lateral proximity. At the southernmost Zagros collision, the Arabia lithosphere is inferred to extend further NE beneath Lut Block. This may be indicative of extended subduction of Arabia beneath Eurasia in southernmost Zagros. We find that eastern Makran shows typical subduction characteristics, with inferred oceanic lithosphere underlying the eastern Oman Sea and hot unstable lithospheric mantle below overriding Helmand Block. Contrastingly, the western Makran subduction zone including Arabia and Eurasia continental sides is underlain by a low-Pn-velocity anomaly, indicative of hot unstable lithospheric mantle. Surface evidence show that western, southern and eastern boundaries of western Makran low-Pn-velocity anomaly may represent a Late Neogene reactivated Precambrian terrane boundary in north Oman.
Figures & Tables
Tectonic Evolution of the Oman Mountains
The Oman Mountains contain one of the world's best- exposed and best-understood fold–thrust belts and the largest, best-exposed and most intensively studied ophiolite complex on Earth. This volume presents new international research from authors currently active in the field focusing on the geology of the Oman Mountains, the foreland region, the carbonate platforms of Northern and Central Oman and the underlying basement complex. In addition there is a particular focus on geoconservation in the region. The volume is divided into three main sections that discuss the tectonics of the Arabian plate using insights from geophysics, petrology, structural geology, geochronology and palaeontology; the petrology and geochemistry of the Oman Ophiolite and the sedimentary and hydrocarbon systems of Oman, drawing on the geophysics, structure and sedimentology of these systems. The volume is enhanced by numerous colour images provided courtesy of Petroleum Development Oman.