3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology, reflection seismics, magnetotellurics and density modelling: Geodynamic speculations
A 3D model of deep crustal structure of the Archaean Karelia Craton and late Palaeoproterozoic Svecofennian Accretionary Orogen including the boundary zone is presented. The model is based on the combination of data from geological mapping and reflection seismic studies, along profiles 1-EU, 4B, FIR...
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ftdoajarticles:oai:doaj.org/article:fd61f9daf7944e78991f752d0e7bf230 2023-10-09T21:53:07+02:00 3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology, reflection seismics, magnetotellurics and density modelling: Geodynamic speculations Michael V. Mints Victor N. Glaznev Olga M. Muravina Elena Yu Sokolova 2020-05-01T00:00:00Z https://doi.org/10.1016/j.gsf.2019.10.003 https://doaj.org/article/fd61f9daf7944e78991f752d0e7bf230 EN eng Elsevier http://www.sciencedirect.com/science/article/pii/S1674987119301975 https://doaj.org/toc/1674-9871 1674-9871 doi:10.1016/j.gsf.2019.10.003 https://doaj.org/article/fd61f9daf7944e78991f752d0e7bf230 Geoscience Frontiers, Vol 11, Iss 3, Pp 999-1023 (2020) Geology QE1-996.5 article 2020 ftdoajarticles https://doi.org/10.1016/j.gsf.2019.10.003 2023-09-10T00:50:54Z A 3D model of deep crustal structure of the Archaean Karelia Craton and late Palaeoproterozoic Svecofennian Accretionary Orogen including the boundary zone is presented. The model is based on the combination of data from geological mapping and reflection seismic studies, along profiles 1-EU, 4B, FIRE-1-2a-2 and FIRE-3-3a, and uses results of magnetotelluric soundings in southern Finland and northern Karelia. A seismogeological model of the crust and crust–mantle boundary is compared with a model of subhorizontal velocity-density layering of the crust. The TTG-type crust of the Palaeoarchaean and Mesoarchaean microcontinents within the Karelia Craton and the Belomorian Province are separated by gently dipping greenstone belts, at least some of which are palaeosutures. The structure of the crust was determined mainly by Palaeoproterozoic tectonism in the intra-continental settings modified by a strong collisional compression at the end of the Palaeoproterozoic. New insights into structure, origin and evolution of the Svecofennian Orogen are provided. The accretionary complex is characterized by inclined tectonic layering: the tectonic sheets, ~15 km thick, are composed of volcanic-sedimentary rocks, including electro-conductive graphite-bearing sedimentary rocks, and electro-resistive granitoids, which plunge monotonously and consecutively eastward. Upon reaching the level of the lower crust, the tectonic sheets of the accretionary complex lose their distinct outlines. In the seismic reflection pattern they are replaced by a uniform acoustically translucent medium, where separate sheets can only be traced fragmentarily. The crust–mantle boundary bears a diffuse character: the transition from crust to mantle is recorded by the disappearance of the vaguely drawn boundaries of the tectonic sheets and in the gradual transition of acoustically homogeneous and translucent lower crust into transparent mantle. Under the effect of endogenic heat flow, the accretionary complex underwent high-temperature metamorphism and ... Article in Journal/Newspaper karelia* Directory of Open Access Journals: DOAJ Articles Geoscience Frontiers 11 3 999 1023 |
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topic |
Geology QE1-996.5 |
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Geology QE1-996.5 Michael V. Mints Victor N. Glaznev Olga M. Muravina Elena Yu Sokolova 3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology, reflection seismics, magnetotellurics and density modelling: Geodynamic speculations |
topic_facet |
Geology QE1-996.5 |
description |
A 3D model of deep crustal structure of the Archaean Karelia Craton and late Palaeoproterozoic Svecofennian Accretionary Orogen including the boundary zone is presented. The model is based on the combination of data from geological mapping and reflection seismic studies, along profiles 1-EU, 4B, FIRE-1-2a-2 and FIRE-3-3a, and uses results of magnetotelluric soundings in southern Finland and northern Karelia. A seismogeological model of the crust and crust–mantle boundary is compared with a model of subhorizontal velocity-density layering of the crust. The TTG-type crust of the Palaeoarchaean and Mesoarchaean microcontinents within the Karelia Craton and the Belomorian Province are separated by gently dipping greenstone belts, at least some of which are palaeosutures. The structure of the crust was determined mainly by Palaeoproterozoic tectonism in the intra-continental settings modified by a strong collisional compression at the end of the Palaeoproterozoic. New insights into structure, origin and evolution of the Svecofennian Orogen are provided. The accretionary complex is characterized by inclined tectonic layering: the tectonic sheets, ~15 km thick, are composed of volcanic-sedimentary rocks, including electro-conductive graphite-bearing sedimentary rocks, and electro-resistive granitoids, which plunge monotonously and consecutively eastward. Upon reaching the level of the lower crust, the tectonic sheets of the accretionary complex lose their distinct outlines. In the seismic reflection pattern they are replaced by a uniform acoustically translucent medium, where separate sheets can only be traced fragmentarily. The crust–mantle boundary bears a diffuse character: the transition from crust to mantle is recorded by the disappearance of the vaguely drawn boundaries of the tectonic sheets and in the gradual transition of acoustically homogeneous and translucent lower crust into transparent mantle. Under the effect of endogenic heat flow, the accretionary complex underwent high-temperature metamorphism and ... |
format |
Article in Journal/Newspaper |
author |
Michael V. Mints Victor N. Glaznev Olga M. Muravina Elena Yu Sokolova |
author_facet |
Michael V. Mints Victor N. Glaznev Olga M. Muravina Elena Yu Sokolova |
author_sort |
Michael V. Mints |
title |
3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology, reflection seismics, magnetotellurics and density modelling: Geodynamic speculations |
title_short |
3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology, reflection seismics, magnetotellurics and density modelling: Geodynamic speculations |
title_full |
3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology, reflection seismics, magnetotellurics and density modelling: Geodynamic speculations |
title_fullStr |
3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology, reflection seismics, magnetotellurics and density modelling: Geodynamic speculations |
title_full_unstemmed |
3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology, reflection seismics, magnetotellurics and density modelling: Geodynamic speculations |
title_sort |
3d model of svecofennian accretionary orogen and karelia craton based on geology, reflection seismics, magnetotellurics and density modelling: geodynamic speculations |
publisher |
Elsevier |
publishDate |
2020 |
url |
https://doi.org/10.1016/j.gsf.2019.10.003 https://doaj.org/article/fd61f9daf7944e78991f752d0e7bf230 |
genre |
karelia* |
genre_facet |
karelia* |
op_source |
Geoscience Frontiers, Vol 11, Iss 3, Pp 999-1023 (2020) |
op_relation |
http://www.sciencedirect.com/science/article/pii/S1674987119301975 https://doaj.org/toc/1674-9871 1674-9871 doi:10.1016/j.gsf.2019.10.003 https://doaj.org/article/fd61f9daf7944e78991f752d0e7bf230 |
op_doi |
https://doi.org/10.1016/j.gsf.2019.10.003 |
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Geoscience Frontiers |
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11 |
container_issue |
3 |
container_start_page |
999 |
op_container_end_page |
1023 |
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1779316354214526976 |