Document Type : Original Research Paper

Authors

1 International Institute of Earthquake Engineering and Seismology, Tehran, Iran

2 Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan, Iran Institut für Geowissenschaften, Johann Wolfgang Goethe-Universität, Altenhöferallee 1, D-60438 Frankfurt am Main, Frankfurt, Germany

Abstract

Crustal structure of the Iranian plateau which is located between two convergent Arabian and Eurasian plates is studied.  Teleseismic earthquakes recorded by broad band stations of Iranian National Seismic Network (INSN) are used to compute the receiver functions for each station. Rayleigh wave phase velocity dispersion curves were estimated employing two-station methods for all possible station pair of the above mentioned seismic network. A combined inversion of Rayleigh wave phase velocities and body wave receiver functions increases the uniqueness of the solution over separate inversions and also facilitates explicit parameterization of layer thickness in the model space. Our result indicates the crustal thickness differs from a minimum of 40 ±2 km in southeast of Iran, (ZHSF) to a maximum of 56 ±2km beneath the Sanandaj-Sirjan zone (SNGE). We observe a crustal thickness of 47 ±2km beneath the central Zagros (GHIR) to 52 ±2km below the eastern most of Zagros (BNDS), then to 47 ±2km beneath the northwestern part of the Zagros (SHGR). Crust of the Central Iran (KRBR) has a thickness of 48 ±2 km while the average Moho depth in southern parts of the Central Alborz (DAMV and THKV stations) is 54±2km. Our analysis shows a thinning of the crust to 43 ±2 km beneath the northwest of Iran (MAKO) and western part of the Caspian basin (GRMI).

Keywords

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