SPECIFIC VELOCITY STRUCTURE OF THE UPPER MANTLE IN THE TRANSBAIKALIA SEGMENT OF THE MONGOLIA-OKHOTSK OROGENIC BELT

The paper presents the results of deep seismic studies on Geophysical Reference Profile 1-SB (Sredneargunsk – Ust-Karenga – Taksimo – Vitim) in East Transbaikalia,Russia. The1200 kmlong profile crosses the major tectonic structures of the Central Asian fold belt: the Argun median massif, the Selenga...

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Main Authors: V. M. Soloviev, V. V. Chechelnitsky, A. S. Salnikov, V. S. Seleznev, A. V. Liseikin, N. A. Galyova
Format: Article
Language:English
Published: Russian Academy of Sciences, Siberian Branch, Institute of the Earth's crust 2017-12-01
Series:Геодинамика и тектонофизика
Subjects:
Online Access:https://www.gt-crust.ru/jour/article/view/487
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author V. M. Soloviev
V. V. Chechelnitsky
A. S. Salnikov
V. S. Seleznev
A. V. Liseikin
N. A. Galyova
author_facet V. M. Soloviev
V. V. Chechelnitsky
A. S. Salnikov
V. S. Seleznev
A. V. Liseikin
N. A. Galyova
author_sort V. M. Soloviev
collection DOAJ
description The paper presents the results of deep seismic studies on Geophysical Reference Profile 1-SB (Sredneargunsk – Ust-Karenga – Taksimo – Vitim) in East Transbaikalia,Russia. The1200 kmlong profile crosses the major tectonic structures of the Central Asian fold belt: the Argun median massif, the Selenga-Stanovoy and Transbaikalia folded regions, and the Baikal rift zone. Its northwestern fragment extends into the Angara-Lena monocline of the Siberian platform. The southeastern (Transbaikalia) and northwestern (Baikal-Patom) fragments of the profile are based on the spot (differential) seismic sounding technique using explosions and 40-tonne vibrators. The south­eastern (Transbaikalia) fragment shows small crustal thickness values (~40 km), an almost horizontal position of the Moho, and high velocities of longitudinal waves (~8.4 km/sec) beneath the Moho. The analysis of parallelism graphs and the dynamic expression of the wave refracted from the Moho suggests a less than 5–10 km thick layer of high velocities and low gradients below Moho. The database on theterritoryofTransbaikaliaincludes ~200 wave arrival times from large earthquakes, which were refracted at the Moho at distances of ~200–1400 km. As part of the tomographic interpretation, using additional DSS data on the Moho, theterritoryofTransbaikaliahas been mapped to show the patterns of the threshold velocity values at the Moho. The seismic data was used to contour an area with high velocity values in the mantle in the central part of the Mongolia-Okhotsk orogenic belt and the neighboring fold structures of Transbaikalia. According to the analysis of the seismic and geologic data on the study area, the mantle layer with high velocity values in the Mongolian-Okhotsk orogenic belt may be represented by the eclogitic rock plates.
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spelling doaj.art-492518575f04469c85b6b9a715bbe25c2023-03-30T20:08:03ZengRussian Academy of Sciences, Siberian Branch, Institute of the Earth's crustГеодинамика и тектонофизика2078-502X2017-12-01841065108210.5800/GT-2017-8-4-0333330SPECIFIC VELOCITY STRUCTURE OF THE UPPER MANTLE IN THE TRANSBAIKALIA SEGMENT OF THE MONGOLIA-OKHOTSK OROGENIC BELTV. M. Soloviev0V. V. Chechelnitsky1A. S. Salnikov2V. S. Seleznev3A. V. Liseikin4N. A. Galyova5Altai-Sayan Branch of Federal Research Center ‘Geophysical Survey of RAS’Baikal Branch of Federal Research Center ‘Geophysical Survey of RAS’Siberian Research Institute of Geology, Geophysics and Mineral ResourcesSeismological Branch of Federal Research Center ‘Geophysical Survey of RAS’Seismological Branch of Federal Research Center ‘Geophysical Survey of RAS’Altai-Sayan Branch of Federal Research Center ‘Geophysical Survey of RAS’The paper presents the results of deep seismic studies on Geophysical Reference Profile 1-SB (Sredneargunsk – Ust-Karenga – Taksimo – Vitim) in East Transbaikalia,Russia. The1200 kmlong profile crosses the major tectonic structures of the Central Asian fold belt: the Argun median massif, the Selenga-Stanovoy and Transbaikalia folded regions, and the Baikal rift zone. Its northwestern fragment extends into the Angara-Lena monocline of the Siberian platform. The southeastern (Transbaikalia) and northwestern (Baikal-Patom) fragments of the profile are based on the spot (differential) seismic sounding technique using explosions and 40-tonne vibrators. The south­eastern (Transbaikalia) fragment shows small crustal thickness values (~40 km), an almost horizontal position of the Moho, and high velocities of longitudinal waves (~8.4 km/sec) beneath the Moho. The analysis of parallelism graphs and the dynamic expression of the wave refracted from the Moho suggests a less than 5–10 km thick layer of high velocities and low gradients below Moho. The database on theterritoryofTransbaikaliaincludes ~200 wave arrival times from large earthquakes, which were refracted at the Moho at distances of ~200–1400 km. As part of the tomographic interpretation, using additional DSS data on the Moho, theterritoryofTransbaikaliahas been mapped to show the patterns of the threshold velocity values at the Moho. The seismic data was used to contour an area with high velocity values in the mantle in the central part of the Mongolia-Okhotsk orogenic belt and the neighboring fold structures of Transbaikalia. According to the analysis of the seismic and geologic data on the study area, the mantle layer with high velocity values in the Mongolian-Okhotsk orogenic belt may be represented by the eclogitic rock plates.https://www.gt-crust.ru/jour/article/view/487deep seismic sounding (dss)velocity of longitudinal waveshodographs from explosions and earthquakesmohomongolia-okhotsk orogenic belt
spellingShingle V. M. Soloviev
V. V. Chechelnitsky
A. S. Salnikov
V. S. Seleznev
A. V. Liseikin
N. A. Galyova
SPECIFIC VELOCITY STRUCTURE OF THE UPPER MANTLE IN THE TRANSBAIKALIA SEGMENT OF THE MONGOLIA-OKHOTSK OROGENIC BELT
Геодинамика и тектонофизика
deep seismic sounding (dss)
velocity of longitudinal waves
hodographs from explosions and earthquakes
moho
mongolia-okhotsk orogenic belt
title SPECIFIC VELOCITY STRUCTURE OF THE UPPER MANTLE IN THE TRANSBAIKALIA SEGMENT OF THE MONGOLIA-OKHOTSK OROGENIC BELT
title_full SPECIFIC VELOCITY STRUCTURE OF THE UPPER MANTLE IN THE TRANSBAIKALIA SEGMENT OF THE MONGOLIA-OKHOTSK OROGENIC BELT
title_fullStr SPECIFIC VELOCITY STRUCTURE OF THE UPPER MANTLE IN THE TRANSBAIKALIA SEGMENT OF THE MONGOLIA-OKHOTSK OROGENIC BELT
title_full_unstemmed SPECIFIC VELOCITY STRUCTURE OF THE UPPER MANTLE IN THE TRANSBAIKALIA SEGMENT OF THE MONGOLIA-OKHOTSK OROGENIC BELT
title_short SPECIFIC VELOCITY STRUCTURE OF THE UPPER MANTLE IN THE TRANSBAIKALIA SEGMENT OF THE MONGOLIA-OKHOTSK OROGENIC BELT
title_sort specific velocity structure of the upper mantle in the transbaikalia segment of the mongolia okhotsk orogenic belt
topic deep seismic sounding (dss)
velocity of longitudinal waves
hodographs from explosions and earthquakes
moho
mongolia-okhotsk orogenic belt
url https://www.gt-crust.ru/jour/article/view/487
work_keys_str_mv AT vmsoloviev specificvelocitystructureoftheuppermantleinthetransbaikaliasegmentofthemongoliaokhotskorogenicbelt
AT vvchechelnitsky specificvelocitystructureoftheuppermantleinthetransbaikaliasegmentofthemongoliaokhotskorogenicbelt
AT assalnikov specificvelocitystructureoftheuppermantleinthetransbaikaliasegmentofthemongoliaokhotskorogenicbelt
AT vsseleznev specificvelocitystructureoftheuppermantleinthetransbaikaliasegmentofthemongoliaokhotskorogenicbelt
AT avliseikin specificvelocitystructureoftheuppermantleinthetransbaikaliasegmentofthemongoliaokhotskorogenicbelt
AT nagalyova specificvelocitystructureoftheuppermantleinthetransbaikaliasegmentofthemongoliaokhotskorogenicbelt