Seismic discontinuities of the western Alborz by analysis of receiver functions and surface waves dispersion

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Abstract

Crustal velocity structure in the Western Alborz have been investigated using joint inversion of receiver functions and Rayleigh wave group velocity dispersion curves.  To determine the receiver functions, time domain iterative deconvolution and teleseismic events, which are recorded at five broadband seismic stations of the Iranian Seismological Center (IRSC), were used. The fundamental mode Rayleigh wave group velocity dispersion curves were provided by the study on the structure of crust and upper mantle of the Iranian Plateau. The results show that the average thickness of the crust in the southern margin of the Caspian Sea beneath of the CSN1 and RST1 stations is 38 km. Toward south, the depth of Moho increases up to 52, 54 and 50 km beneath the QALM, QCNT and QSDN stations. The low thickness of the crust in the southern shore of the Caspian Sea indicates that the Caspian crust is thin. Moreover, the moderate thickness of the crust in western Alborz, which is not in balance with its elevation, indicates the lack of root in Alborz.

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References

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Volume 7, Issue 2
January 0
Pages 173-183

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