Seismic velocity structure across the Fennoscandia-Sarmatia suture of the East European Craton beneath the EUROBRIDGE profile through Lithuania and Belarus
During EUROBRIDGE"96 seismic data were acquired along a 544-km NW-SE profile, from the East Lithuanian Belt (EL) to the Ukrainian Shield. Explosive sources from 16 shotpoints at 30-km intervals were recorded by 114 three-component seismographs deployed at 3-4-km intervals along the profile. Tom...
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ftgfzpotsdam:oai:gfzpublic.gfz-potsdam.de:item_227883 2023-05-15T16:11:52+02:00 Seismic velocity structure across the Fennoscandia-Sarmatia suture of the East European Craton beneath the EUROBRIDGE profile through Lithuania and Belarus Doody, J. Giese, R. Grad, M. Thybo, H. 2.2 Geophysical Deep Sounding, 2.0 Physics of the Earth, Departments, GFZ Publication Database, Deutsches GeoForschungsZentrum 1999 https://gfzpublic.gfz-potsdam.de/pubman/item/item_227883 unknown https://gfzpublic.gfz-potsdam.de/pubman/item/item_227883 Tectonophysics 550 - Earth sciences info:eu-repo/semantics/article 1999 ftgfzpotsdam 2022-09-14T05:56:28Z During EUROBRIDGE"96 seismic data were acquired along a 544-km NW-SE profile, from the East Lithuanian Belt (EL) to the Ukrainian Shield. Explosive sources from 16 shotpoints at 30-km intervals were recorded by 114 three-component seismographs deployed at 3-4-km intervals along the profile. Tomographic inversion and raytrace modelling, integrated with results from the EUROBRIDGE"95 experiment, established a two-dimensional P-wave velocity lithospheric model and the spatial variation of Vp/Vs. Sedimentary cover in Belarus consists of two principal layers with P-wave velocities of about 2.3 and 4.0 km/s. Upper, middle and lower crystalline crust exhibit velocities of 6.1-6.3, 6.4-6.8 and 6.9-7.2 km/s, and are characterised by low velocity gradients and small contrasts at boundaries. The crust below Belarus is about 50 km thick with Moho elevations of a few kilometres. Mantle P-wave velocities immediately beneath the Moho are generally 8.2-8.4 km/s. A lower lithosphere reflector occurs at 65-70 km depth. S-wave velocities are high in the upper crust and low in the lower crust. Our crustal model shows similarities to results from Scandinavia. High lower-crustal velocities and a crustal thickness of about 50 km (common features of Proterozoic crust) are observed throughout the EUROBRIDGE"96 profile. The boundary between the EL and West Lithuanian Granulite Domain (WLG) is associated with pronounced crustal velocity changes, and a thinning of crust towards the northwest. The WLG may be part of a larger southern Baltic Sea tectonic unit. Correlation of our seismic structure with near-surface geology tentatively suggests that contact zones between the EL, Belarus-Baltic Granulite Domain, Central Belarussian Belt (CB), and the Osnitsk-Mikashevichi Igneous Belt all dip slightly to the southeast, consistent with successive docking of the terranes during craton growth. A spectacular feature of our model is high velocities throughout the CB crust, which marks the Fennoscandia-Sarmatia suture. Here we observe a change from ... Article in Journal/Newspaper Fennoscandia GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam) |
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Open Polar |
collection |
GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam) |
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ftgfzpotsdam |
language |
unknown |
topic |
550 - Earth sciences |
spellingShingle |
550 - Earth sciences Doody, J. Giese, R. Grad, M. Thybo, H. Seismic velocity structure across the Fennoscandia-Sarmatia suture of the East European Craton beneath the EUROBRIDGE profile through Lithuania and Belarus |
topic_facet |
550 - Earth sciences |
description |
During EUROBRIDGE"96 seismic data were acquired along a 544-km NW-SE profile, from the East Lithuanian Belt (EL) to the Ukrainian Shield. Explosive sources from 16 shotpoints at 30-km intervals were recorded by 114 three-component seismographs deployed at 3-4-km intervals along the profile. Tomographic inversion and raytrace modelling, integrated with results from the EUROBRIDGE"95 experiment, established a two-dimensional P-wave velocity lithospheric model and the spatial variation of Vp/Vs. Sedimentary cover in Belarus consists of two principal layers with P-wave velocities of about 2.3 and 4.0 km/s. Upper, middle and lower crystalline crust exhibit velocities of 6.1-6.3, 6.4-6.8 and 6.9-7.2 km/s, and are characterised by low velocity gradients and small contrasts at boundaries. The crust below Belarus is about 50 km thick with Moho elevations of a few kilometres. Mantle P-wave velocities immediately beneath the Moho are generally 8.2-8.4 km/s. A lower lithosphere reflector occurs at 65-70 km depth. S-wave velocities are high in the upper crust and low in the lower crust. Our crustal model shows similarities to results from Scandinavia. High lower-crustal velocities and a crustal thickness of about 50 km (common features of Proterozoic crust) are observed throughout the EUROBRIDGE"96 profile. The boundary between the EL and West Lithuanian Granulite Domain (WLG) is associated with pronounced crustal velocity changes, and a thinning of crust towards the northwest. The WLG may be part of a larger southern Baltic Sea tectonic unit. Correlation of our seismic structure with near-surface geology tentatively suggests that contact zones between the EL, Belarus-Baltic Granulite Domain, Central Belarussian Belt (CB), and the Osnitsk-Mikashevichi Igneous Belt all dip slightly to the southeast, consistent with successive docking of the terranes during craton growth. A spectacular feature of our model is high velocities throughout the CB crust, which marks the Fennoscandia-Sarmatia suture. Here we observe a change from ... |
author2 |
2.2 Geophysical Deep Sounding, 2.0 Physics of the Earth, Departments, GFZ Publication Database, Deutsches GeoForschungsZentrum |
format |
Article in Journal/Newspaper |
author |
Doody, J. Giese, R. Grad, M. Thybo, H. |
author_facet |
Doody, J. Giese, R. Grad, M. Thybo, H. |
author_sort |
Doody, J. |
title |
Seismic velocity structure across the Fennoscandia-Sarmatia suture of the East European Craton beneath the EUROBRIDGE profile through Lithuania and Belarus |
title_short |
Seismic velocity structure across the Fennoscandia-Sarmatia suture of the East European Craton beneath the EUROBRIDGE profile through Lithuania and Belarus |
title_full |
Seismic velocity structure across the Fennoscandia-Sarmatia suture of the East European Craton beneath the EUROBRIDGE profile through Lithuania and Belarus |
title_fullStr |
Seismic velocity structure across the Fennoscandia-Sarmatia suture of the East European Craton beneath the EUROBRIDGE profile through Lithuania and Belarus |
title_full_unstemmed |
Seismic velocity structure across the Fennoscandia-Sarmatia suture of the East European Craton beneath the EUROBRIDGE profile through Lithuania and Belarus |
title_sort |
seismic velocity structure across the fennoscandia-sarmatia suture of the east european craton beneath the eurobridge profile through lithuania and belarus |
publishDate |
1999 |
url |
https://gfzpublic.gfz-potsdam.de/pubman/item/item_227883 |
genre |
Fennoscandia |
genre_facet |
Fennoscandia |
op_source |
Tectonophysics |
op_relation |
https://gfzpublic.gfz-potsdam.de/pubman/item/item_227883 |
_version_ |
1765997074132762624 |