Anatolian surface wave evaluated at GEOFON Station ISP Isparta, Turkey


Erduran M. , Cakir O. , Tezel T. , SAHIN Ş., ALPTEKIN O.

TECTONOPHYSICS, cilt.434, ss.39-54, 2007 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 434
  • Basım Tarihi: 2007
  • Doi Numarası: 10.1016/j.tecto.2007.02.005
  • Dergi Adı: TECTONOPHYSICS
  • Sayfa Sayıları: ss.39-54

Özet

We have studied seismic surface waves of 255 shallow regional earthquakes recently recorded at GEOFON station ISP (Isparta, Turkey) and have selected these 52 recordings with high signal-to-noise ratio for further analysis. An attempt was made by the simultaneous use of the Rayleigh and Love surface wave data to interpret the planar crust and uppermost mantle velocity structure beneath the Anatolian plate using a differential least-square inversion technique. The shear-wave velocities near the surface show a gradational change from approximately 2.2 to 3.6 km s(-1) in the depth range 0-10 km. The mid-crustal depth range indicating a weakly developed low velocity zone has shear-wave velocities around 3.55 km s(-1). The Moho discontinuity characterizing the crust-mantle velocity transition appears somewhat gradual between the depth range similar to 25-45 km. The surface waves approaching from the northern Anatolia are estimated to travel a crustal thickness of similar to 33 km whilst those from the southwestern Anatolia and part of east Mediterranean Sea indicate a thicker crust at similar to 37 km. The eastern Anatolia events traveled even thicker crust at similar to 41 km. A low sub-Moho velocity is estimated at similar to 4.27 km s(-1), although consistent with other similar studies in the region. The current velocities are considerably slower than indicated by the Preliminary Reference Earth Model (PREM) in almost all depth ranges. (c) 2007 Elsevier B.V. All rights reserved.