Thickness of Crust in the West of Iran Obtained from Modeling of Ps Converted Waves

نویسندگان

1 M.Sc. Student, Department of Physics, Qom Branch, Islamic Azad University, Qom, Iran

2 Associate Professor, Department of Physics, Qom Branch, Islamic Azad University, Qom, Iran

3 Assistant Professor, Department of Civil Engineering, Nowshahr Branch, Islamic Azad University, Nowshahr, Iran

چکیده

Receiver functions are usually used to detect Ps converted waves and are especially useful to picture seismic discontinuities in the crust and upper mantle. In this study, the P receiver function technique beneath the west Iran is used to map out the lateral variation of the Moho boundary. The teleseismic data (Mb ≥5.5, epicentral distance between 30˚-95˚) recorded from 2004 to 2016 at 17 permanent broadband and short-period stations of the Iranian Seismological Center (ISC, http://irsc.ut.ac.ir) of Kermanshah, Khoramabad, Hamedan and Boroujerd and one broadband station of the International Institute of Earthquake Engineering and Seismology (IIEES, http://www.iiees.ac.ir) were used. The results indicate clear Ps conversions at the Moho boundary. The Moho depths are estimated from the delay time of the Moho converted phase relative to the direct P wave beneath each network. The average Moho depth lies at ~42±2 km. Furthermore, the clear image of the Moho at depths as modeling of PRF, ranging from 37 km beneath KCHF station to maximum 55 km beneath HAGD station was presented. According to the distribution and number of stations used, this study is more comprehensive than previous studies.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Thickness of Crust in the West of Iran Obtained from Modeling of Ps Converted Waves

نویسندگان [English]

  • Mohadeseh Sadat Khatami 1
  • Fataneh Taghizadeh-Farahmand 2
  • Narges Afsari 3
1 M.Sc. Student, Department of Physics, Qom Branch, Islamic Azad University, Qom, Iran
2 Associate Professor, Department of Physics, Qom Branch, Islamic Azad University, Qom, Iran
3 Assistant Professor, Department of Civil Engineering, Nowshahr Branch, Islamic Azad University, Nowshahr, Iran
چکیده [English]

Receiver functions are usually used to detect Ps converted waves and are especially useful to picture seismic discontinuities in the crust and upper mantle. In this study, the P receiver function technique beneath the west Iran is used to map out the lateral variation of the Moho boundary. The teleseismic data (Mb ≥5.5, epicentral distance between 30˚-95˚) recorded from 2004 to 2016 at 17 permanent broadband and short-period stations of the Iranian Seismological Center (ISC, http://irsc.ut.ac.ir) of Kermanshah, Khoramabad, Hamedan and Boroujerd and one broadband station of the International Institute of Earthquake Engineering and Seismology (IIEES, http://www.iiees.ac.ir) were used. The results indicate clear Ps conversions at the Moho boundary. The Moho depths are estimated from the delay time of the Moho converted phase relative to the direct P wave beneath each network. The average Moho depth lies at ~42±2 km. Furthermore, the clear image of the Moho at depths as modeling of PRF, ranging from 37 km beneath KCHF station to maximum 55 km beneath HAGD station was presented. According to the distribution and number of stations used, this study is more comprehensive than previous studies.

کلیدواژه‌ها [English]

  • P receiver function
  • Crustal Structure
  • Converted Waves
  • Northwest of Zagros
  • Iran

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