TY - JOUR

T1 - Ongoing formation of felsic lower crustal channel by relamination in Zagros collision zone revealed from regional tomography

AU - Talebi, Amir

AU - Koulakov, Ivan

AU - Moradi, Ali

AU - Rahimi, Habib

AU - Gerya, Taras

PY - 2020/5/19

Y1 - 2020/5/19

N2 - Complex interaction of rheologically contrasting layers within the lithosphere during the collision of continental plates leads to active faulting, which represents a serious hazard to the population and infrastructure. One of the collision scenarios presumes the existence of a middle-lower crustal channel composed of subducted silicic upper crustal rocks, which is thought to exist in the Tibetan-Himalayan system. Based on the results of seismic tomography, we argue that a similar mechanism of crustal channeling takes place beneath the Zagros mountain system in southwestern Iran. The 3D seismic velocity model reveals an inverted crustal architecture of the collision zone, in which the low-velocity felsic (granitic and sedimentary) upper crustal rocks of the Arabian plate form a seismically inactive lower crustal channel below the higher-velocity mafic (basaltic) middle-upper crustal layer of the Iranian crust. Based on existing numerical models, we suggest that the formation of the felsic channel is likely governed by separation (delamination) of the weak felsic upper crust of the subducting Arabian lithosphere and its ductile underplating under rheologically stronger upper-middle crust of the Iranian plate.

AB - Complex interaction of rheologically contrasting layers within the lithosphere during the collision of continental plates leads to active faulting, which represents a serious hazard to the population and infrastructure. One of the collision scenarios presumes the existence of a middle-lower crustal channel composed of subducted silicic upper crustal rocks, which is thought to exist in the Tibetan-Himalayan system. Based on the results of seismic tomography, we argue that a similar mechanism of crustal channeling takes place beneath the Zagros mountain system in southwestern Iran. The 3D seismic velocity model reveals an inverted crustal architecture of the collision zone, in which the low-velocity felsic (granitic and sedimentary) upper crustal rocks of the Arabian plate form a seismically inactive lower crustal channel below the higher-velocity mafic (basaltic) middle-upper crustal layer of the Iranian crust. Based on existing numerical models, we suggest that the formation of the felsic channel is likely governed by separation (delamination) of the weak felsic upper crust of the subducting Arabian lithosphere and its ductile underplating under rheologically stronger upper-middle crust of the Iranian plate.

KW - LITHOSPHERIC STRUCTURE BENEATH

KW - MOUNTAIN BELT

KW - SUTURE ZONE

KW - IRAN

KW - TECTONICS

KW - CONSTRAINTS

KW - MANTLE

KW - WAVE

KW - DEFORMATION

KW - EVOLUTION

UR - http://www.scopus.com/inward/record.url?scp=85084964541&partnerID=8YFLogxK

U2 - 10.1038/s41598-020-64946-w

DO - 10.1038/s41598-020-64946-w

M3 - Article

C2 - 32427975

AN - SCOPUS:85084964541

VL - 10

JO - Scientific Reports

JF - Scientific Reports

SN - 2045-2322

IS - 1

M1 - 8224

ER -