Advanced Applied Geology

Advanced Applied Geology

Estimation of crustal depth using P-wave receiver functions in South Khorasan province

Authors
1 Bahonar Un. Kerman
2 Department of Geology, Shahid Bahonar University of Kerman, Kerman, Iran
3 Department of Geology, Azad University of Kerman
Abstract
Estimation of the crustal structure and upper mantle is one of the important goals in geophysical studies. There are few geophysical methods for subsurface investigations, but, in this research, teleseismic earthquake waveforms (with a magnitude greater than 5.5 and also an epicentral distance of 25 º -90º) were selected during six years to obtain their receiver functions in the South Khorasan network stations. After checking the waveforms in IRIS list, the time window was selected in waveforms. Then horizontal components were rotated in the direction of lateral angle to obtain the radial and tangential components. Using Liguria and Amon's repetitive deconvolution method, vertical component was extracted from radial component in the time domain, then a Gaussian filter with a width of 1 was applied. After calculating the receiver functions and classifying them into back-azimuth intervals and 10-degree epicentral distance, the stacking is done to increase the signal-to-noise ratio. The simultaneous conversion of two independent datasets by considering the proportional weighted parameters of their combinations to find a velocity model was implemented using Herman and Amon software. Minimizing standard error between the real and predicted data is criterion to reach the desired model close to the real model of the earth. The results of this study show that the boundary of the Moho discontinuity is 43±2 km under the Koohdasht station (TKDS), 43±2 km under the Afriz station (AFRZ) and 41±2 km under the Nehbandan station (NHDN). According to data and methods used, the error analysis is within the acceptable range.
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