Research output: Contribution to journal › Article › peer-review
Seismic structure of the crust and uppermost mantle beneath Caucasus based on regional earthquake tomography. / Zabelina, Irina; Koulakov, Ivan; Amanatashvili, Iason et al.
In: Journal of Asian Earth Sciences, Vol. 119, 01.04.2016, p. 87-99.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Seismic structure of the crust and uppermost mantle beneath Caucasus based on regional earthquake tomography
AU - Zabelina, Irina
AU - Koulakov, Ivan
AU - Amanatashvili, Iason
AU - El Khrepy, Sami
AU - Al-Arifi, Nassir
PY - 2016/4/1
Y1 - 2016/4/1
N2 - We present a new seismic model of the crust beneath the Caucasus based on tomographic inversion of P and S arrival times from earthquakes occurred in the region recorded by regional seismic networks in the Caucasian republics. The resulting P and S velocity models clearly delineate major tectonic units of the study area. A high velocity anomaly in Transcaucasian separating the Great and Lesser Caucasus possibly represents a rigid crustal block corresponding to the remnant oceanic lithosphere of Tethys. Another high-velocity pattern coincides with the southern edge of the Scythian Plate. Strongly deformed areas of Great and Lesser Caucasus are mostly associated with low-velocity patterns representing thickened felsic part of the crust and strong fracturing of rocks. Most Cenozoic volcanic centers of Caucasus match to the low-velocity seismic anomalies in the crust. For example, the Kazbegi volcano group is located above an elongated low-velocity anomaly squeezed between high-velocity segments of Transcaucasian and Scythian Plate. We propose that mantle part of the Arabian and Eurasian Plates has been delaminated due to the continental collision in the Caucasus region. As a result, overheated asthenosphere appeared nearly the bottom of the crust and facilitated melting of the crustal material that caused the origin of recent volcanism in Great and Lesser Caucasus.
AB - We present a new seismic model of the crust beneath the Caucasus based on tomographic inversion of P and S arrival times from earthquakes occurred in the region recorded by regional seismic networks in the Caucasian republics. The resulting P and S velocity models clearly delineate major tectonic units of the study area. A high velocity anomaly in Transcaucasian separating the Great and Lesser Caucasus possibly represents a rigid crustal block corresponding to the remnant oceanic lithosphere of Tethys. Another high-velocity pattern coincides with the southern edge of the Scythian Plate. Strongly deformed areas of Great and Lesser Caucasus are mostly associated with low-velocity patterns representing thickened felsic part of the crust and strong fracturing of rocks. Most Cenozoic volcanic centers of Caucasus match to the low-velocity seismic anomalies in the crust. For example, the Kazbegi volcano group is located above an elongated low-velocity anomaly squeezed between high-velocity segments of Transcaucasian and Scythian Plate. We propose that mantle part of the Arabian and Eurasian Plates has been delaminated due to the continental collision in the Caucasus region. As a result, overheated asthenosphere appeared nearly the bottom of the crust and facilitated melting of the crustal material that caused the origin of recent volcanism in Great and Lesser Caucasus.
KW - Caucasus
KW - Collision
KW - Crust
KW - Mantle
KW - Seismic tomography
KW - Volcanism
UR - http://www.scopus.com/inward/record.url?scp=84955118655&partnerID=8YFLogxK
U2 - 10.1016/j.jseaes.2016.01.010
DO - 10.1016/j.jseaes.2016.01.010
M3 - Article
AN - SCOPUS:84955118655
VL - 119
SP - 87
EP - 99
JO - Journal of Asian Earth Sciences
JF - Journal of Asian Earth Sciences
SN - 1367-9120
ER -
ID: 25707938