Seismological constraints on the lithosphere-asthenosphere system beneath the central and east Iranian Plateau

Zarunizadeh，Z.1; Motaghi，K.1; Movaghari，R.2; Yang，Y.2; Priestley，K.3

2024-02-23

10.1016/j.tecto.2024.230215

Tectonophysics   影响因子和分区

0040-1951

The lithosphere-asthenosphere system beneath the central and eastern parts of the Iranian Plateau is investigated using a two-plane wave surface-wave tomography. We analyzed 11,430 teleseismic Rayleigh waveforms collected from 59 seismic stations and generated phase velocity maps at nine periods ranging from 25 s to 111 s. By inverting the phase velocity dispersion data, we constructed a 3-D S-wave velocity (Vs) model from the surface down to a depth of 200 km. Our investigation reveals a low-velocity anomaly within the uppermost mantle beneath the Iranian Plateau, presenting a sharp contrast to a high-velocity lithospheric mantle beneath the Zagros suture. This low-velocity anomaly characterizes an asthenospheric channel beneath the Iranian Plateau, where velocity varies non-uniformly, with the lowest Vs values located beneath areas of sparse Pliocene-Quaternary post-collisional volcanic activity in the Iranian Plateau. These observations might support the hypothesis of small-scale convection initiated after the Arabia-Eurasia continental collision. Furthermore, we explore the effect of the observed velocity anomalies on the isostatic compensation. We show that the local variations in both crustal thickness and upper mantle density account for the isostatic compensation of the surface topography in the Iranian Plateau. These factors may have interacted to shape the Plateau evolution and deformation over time.

Geodynamic evolution Iranian Plateau Isostatic compensation Surface wave tomography

SCI ; EI

英语

其他

GEOSCIENCES

2-s2.0-85182924710

Scopus

1.Department of Earth Sciences,Institute for Advanced Studies in Basic Sciences (IASBS),Zanjan,45137-66731,Iran
2.Department of Earth and Space Sciences,Southern University of Science and Technology,Shenzhen,518055,China
3.Bullard Laboratories,University of Cambridge,Cambridge,United Kingdom

Zarunizadeh，Z.,Motaghi，K.,Movaghari，R.,et al. Seismological constraints on the lithosphere-asthenosphere system beneath the central and east Iranian Plateau[J]. Tectonophysics,2024,873.

Zarunizadeh，Z.,Motaghi，K.,Movaghari，R.,Yang，Y.,&Priestley，K..(2024).Seismological constraints on the lithosphere-asthenosphere system beneath the central and east Iranian Plateau.Tectonophysics,873.

Zarunizadeh，Z.,et al."Seismological constraints on the lithosphere-asthenosphere system beneath the central and east Iranian Plateau".Tectonophysics 873(2024).