Crustal Structure of the Northern Lut Block in Eastern Iran Using P Wave Receiver Function Migration

Document Type : Research Article

Authors

1 PhD. Student, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, ran

2 Assistant Professor, Seismological Research Center, Department of Geology, International Institute of Seismology and Earthquake Engineering (IIEES), Tehran, Iran

3 Associate Professor, Seismological Research Center, Department of Geology, International Institute of Seismology and Earthquake Engineering (IIEES), Tehran, Iran

Abstract

To investigate the crustal structure of the northeast of Lut block and Eastern Iranian Ranges, we deployed 31 seismic stations along a 230 km profile for a period of approximately 9 months. Using the migration of P-wave receiver functions, we analyzed changes in the Moho depth along this profile. Our results indicate that the boundary between the crust and upper mantle is nearly flat, with a depth of approximately 40 km. Furthermore, we found that the thickness of the crust is relatively high beneath the Lut-Afghan Block boundaries and Bagheran Mountain, where receiver functions suggest the presence of more complex structures including inclined interfaces. Our findings suggest that the collision of Lut-Afghan blocks has not significantly increased the crustal thickness in the northeast Iran compared to the Zagros collision zone in the southwest of Iran. Rather, we propose that the observed shortening in this region is primarily due to the interaction of strike-slip motions, which can accommodate shortening through mechanisms such as rotation and wedge escaping.

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