TY - JOUR

T1 - 3D seismic tomography models of the Baikal Rift zone and surrounding areas based on regional seismological data

AU - Medved, Irina

AU - Komzeleva, Viktoria

AU - Koulakov, Ivan

AU - Buslov, Mikhail

AU - Filippova, Alena

N1 - The studies were carried out within research projects of NSU, IPGG SB RAS, IGM SB RAS and IZMIRAN. The work was supported by the Ministry of Education and Science of Russia. The data used in the work were obtained with large-scale research facilities «Seismic infrasound array for monitoring Arctic cryolitozone and continuous seismic monitoring of the Russian Federation, neighbouring territories and the world». The work on data processing was supported by the state assignment according to the research project АААА-А19-119011490129-0. The work on overview of geology was supported by RFBR grant No. 19-35-60002. The work on seismic tomography of the region was supported by the state assignment according to the research project FSUS-2022-0019. The work on interpretation of the results was supported by the state assignment according to the research project FWZZ-2022-0017. We are very grateful to Kelly Liu and Vineet Kumar Gahalaut for the very constructive reviews, which helped us to improve the paper. Публикация для корректировки.

PY - 2023/6/15

Y1 - 2023/6/15

N2 - We present seismic tomography models of the Baikal Rift Zone (BRZ), obtained from regional seismological data recorded in the period 1994–2016. 3D models of P- and S-wave velocity distributions under the BRZ were built down to a depth of 60 km with the LOTOS local seismic tomography algorithm. An overall picture of the heterogeneities coincides with the already existing ideas on the seismic structure of the region: a high-velocity anomaly in the north corresponds to the Siberian Craton; low-velocity anomalies in the western part of the study area are apparently due to the presence of the Cenozoic plume; the Baikal Rift Zone is characterized by a low-velocity anomaly down to a depth of 35–50 km, which accords with the present-day concepts of the Moho discontinuity depth. Moreover, below the BRZ there is a jump in the lower boundary of the low-velocity anomaly, which is in line with the Moho jump recognized in the existing investigations. In addition, based on the results obtained, we identified a number of heterogeneities not revealed earlier. For example, high-velocity near-surface anomalies in the Middle Baikal block, which were interpreted as heavy gabbro-metagabbro bodies, displaced as a result of the Cenozoic strike-slip. Based on the results obtained, as well as on the review of the existing geological and geophysical works, the authors argue in favor of a passive model during the formation of the Baikal Rift.

AB - We present seismic tomography models of the Baikal Rift Zone (BRZ), obtained from regional seismological data recorded in the period 1994–2016. 3D models of P- and S-wave velocity distributions under the BRZ were built down to a depth of 60 km with the LOTOS local seismic tomography algorithm. An overall picture of the heterogeneities coincides with the already existing ideas on the seismic structure of the region: a high-velocity anomaly in the north corresponds to the Siberian Craton; low-velocity anomalies in the western part of the study area are apparently due to the presence of the Cenozoic plume; the Baikal Rift Zone is characterized by a low-velocity anomaly down to a depth of 35–50 km, which accords with the present-day concepts of the Moho discontinuity depth. Moreover, below the BRZ there is a jump in the lower boundary of the low-velocity anomaly, which is in line with the Moho jump recognized in the existing investigations. In addition, based on the results obtained, we identified a number of heterogeneities not revealed earlier. For example, high-velocity near-surface anomalies in the Middle Baikal block, which were interpreted as heavy gabbro-metagabbro bodies, displaced as a result of the Cenozoic strike-slip. Based on the results obtained, as well as on the review of the existing geological and geophysical works, the authors argue in favor of a passive model during the formation of the Baikal Rift.

KW - Baikal Rift Zone

KW - Collision zone

KW - Crustal structure

KW - Eastern Sayan

KW - Geodynamics

KW - Neotectonics

KW - Rift zone

KW - Seismic tomography

KW - Siberian Platform

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85150425474&origin=inward&txGid=1891d81dc634ea5c27d117fdb532721a

UR - https://www.mendeley.com/catalogue/919cf192-1217-3840-ba2e-2648093049d5/

U2 - 10.1016/j.jseaes.2023.105619

DO - 10.1016/j.jseaes.2023.105619

M3 - Article

VL - 249

JO - Journal of Asian Earth Sciences

JF - Journal of Asian Earth Sciences

SN - 1367-9120

M1 - 105619

ER -