Postglacial tectonics and palaeoseisic dislocation in the Kovda area (Kandalaksha Bay, eastern Fennoscandian Shield)
The Kandalaksha Graben of the White Sea is one of the most active tectonic zones of the eastern part of the Fennoscandian crystalline shield. Active faults of the Kandalaksha Graben derive from the axial zone of the Paleoproterozoic mobile Lapland Granulite Belt and the Riphean paleorift system. The...
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ftstpetersburgun:oai:dspace.spbu.ru:11701/16758 2023-05-15T16:12:54+02:00 Postglacial tectonics and palaeoseisic dislocation in the Kovda area (Kandalaksha Bay, eastern Fennoscandian Shield) Nikolaeva, Svetlana B. 2019-09 https://doi.org/10.21638/spbu07.2019.304 http://hdl.handle.net/11701/16758 ru rus St Petersburg State University Vestnik of St Petersburg University. Earth Sciences;Volume 64; Issue 3 Nikolaeva S. B. (2019). Postglacial tectonics and palaeoseisic dislocation in the Kovda area (Kandalaksha Bay, eastern Fennoscandian Shield). Vestnik of Saint Petersburg University. Earth Sciences, 64 (3), 434–453. https://doi.org/10.21638/spbu07.2019.304 http://hdl.handle.net/11701/16758 postglacial faults palaeoearthquakes seismic dislocations shifting of rock masses Holocene Kandalaksha Graben Kolvitsky Graben White Sea Fennoscandian Shield Article 2019 ftstpetersburgun https://doi.org/10.21638/spbu07.2019.304 2019-12-10T00:47:10Z The Kandalaksha Graben of the White Sea is one of the most active tectonic zones of the eastern part of the Fennoscandian crystalline shield. Active faults of the Kandalaksha Graben derive from the axial zone of the Paleoproterozoic mobile Lapland Granulite Belt and the Riphean paleorift system. The system of active faults limits the northern and southern sides of the Kandalaksha Graben. An important problem is the study of the paleoseismicity of this zone. Local late- and postglacial rock dislocations and shifts, which occur due to strong seismic effects in the Kovda area of Kandalaksha Bay of the White Sea, are considered in the present paper. We consider the signs which testify to the dynamic (seismic) impact on rocks. In our work it is shown that paleoseisic dislocations are developed much wider and cover more representative land areas than previously reported. The dislocation concentration is in the area of about 325 km2. This area is the supposed epicenter of ancient seismic events that occurred repeatedly at the end of the Late Pleistocene and during the Holocene. According to radiocarbon analysis and the time of the opening of the seismic gorge, the age of the seismic event was determined about 7060 ± 160 yr cal BP. It has been established that disturbances of rocks are predominant seismogravitational and seismic vibrational types. They are formed by earthquakes of intensity > VIII degrees on the MSK-64 scale. Paleoseismic dislocations are localized in zones of active lineaments as well as confined to contacts of rocks of different petrographic composition. The directions of active fractures coincide with the strike of fracture in the fault scarps and gorges. This predetermines their seismic activation in the Late Pleistocene and Holocene. The main seismogenic fault is probably the fault-shift of young Kolvitsky Graben. Smaller-scale faults are considered as secondary feathering faults. Исследования выполнены в Федеральном государственном бюджетном учреждении науки Федерального исследовательского центра «Кольский научный центр РАН», Геологический институт (ГИ КНЦ РАН) по теме госзадания 0226-2019-0054. Article in Journal/Newspaper Fennoscandian White Sea Lapland Saint Petersburg State University: Research Repository (DSpace SPbU) White Sea Kandalaksha ENVELOPE(32.417,32.417,67.133,67.133) Kovda ENVELOPE(32.861,32.861,66.679,66.679) Vestnik of Saint Petersburg University. Earth Sciences 64 3 434 453 |
institution |
Open Polar |
collection |
Saint Petersburg State University: Research Repository (DSpace SPbU) |
op_collection_id |
ftstpetersburgun |
language |
Russian |
topic |
postglacial faults palaeoearthquakes seismic dislocations shifting of rock masses Holocene Kandalaksha Graben Kolvitsky Graben White Sea Fennoscandian Shield |
spellingShingle |
postglacial faults palaeoearthquakes seismic dislocations shifting of rock masses Holocene Kandalaksha Graben Kolvitsky Graben White Sea Fennoscandian Shield Nikolaeva, Svetlana B. Postglacial tectonics and palaeoseisic dislocation in the Kovda area (Kandalaksha Bay, eastern Fennoscandian Shield) |
topic_facet |
postglacial faults palaeoearthquakes seismic dislocations shifting of rock masses Holocene Kandalaksha Graben Kolvitsky Graben White Sea Fennoscandian Shield |
description |
The Kandalaksha Graben of the White Sea is one of the most active tectonic zones of the eastern part of the Fennoscandian crystalline shield. Active faults of the Kandalaksha Graben derive from the axial zone of the Paleoproterozoic mobile Lapland Granulite Belt and the Riphean paleorift system. The system of active faults limits the northern and southern sides of the Kandalaksha Graben. An important problem is the study of the paleoseismicity of this zone. Local late- and postglacial rock dislocations and shifts, which occur due to strong seismic effects in the Kovda area of Kandalaksha Bay of the White Sea, are considered in the present paper. We consider the signs which testify to the dynamic (seismic) impact on rocks. In our work it is shown that paleoseisic dislocations are developed much wider and cover more representative land areas than previously reported. The dislocation concentration is in the area of about 325 km2. This area is the supposed epicenter of ancient seismic events that occurred repeatedly at the end of the Late Pleistocene and during the Holocene. According to radiocarbon analysis and the time of the opening of the seismic gorge, the age of the seismic event was determined about 7060 ± 160 yr cal BP. It has been established that disturbances of rocks are predominant seismogravitational and seismic vibrational types. They are formed by earthquakes of intensity > VIII degrees on the MSK-64 scale. Paleoseismic dislocations are localized in zones of active lineaments as well as confined to contacts of rocks of different petrographic composition. The directions of active fractures coincide with the strike of fracture in the fault scarps and gorges. This predetermines their seismic activation in the Late Pleistocene and Holocene. The main seismogenic fault is probably the fault-shift of young Kolvitsky Graben. Smaller-scale faults are considered as secondary feathering faults. Исследования выполнены в Федеральном государственном бюджетном учреждении науки Федерального исследовательского центра «Кольский научный центр РАН», Геологический институт (ГИ КНЦ РАН) по теме госзадания 0226-2019-0054. |
format |
Article in Journal/Newspaper |
author |
Nikolaeva, Svetlana B. |
author_facet |
Nikolaeva, Svetlana B. |
author_sort |
Nikolaeva, Svetlana B. |
title |
Postglacial tectonics and palaeoseisic dislocation in the Kovda area (Kandalaksha Bay, eastern Fennoscandian Shield) |
title_short |
Postglacial tectonics and palaeoseisic dislocation in the Kovda area (Kandalaksha Bay, eastern Fennoscandian Shield) |
title_full |
Postglacial tectonics and palaeoseisic dislocation in the Kovda area (Kandalaksha Bay, eastern Fennoscandian Shield) |
title_fullStr |
Postglacial tectonics and palaeoseisic dislocation in the Kovda area (Kandalaksha Bay, eastern Fennoscandian Shield) |
title_full_unstemmed |
Postglacial tectonics and palaeoseisic dislocation in the Kovda area (Kandalaksha Bay, eastern Fennoscandian Shield) |
title_sort |
postglacial tectonics and palaeoseisic dislocation in the kovda area (kandalaksha bay, eastern fennoscandian shield) |
publisher |
St Petersburg State University |
publishDate |
2019 |
url |
https://doi.org/10.21638/spbu07.2019.304 http://hdl.handle.net/11701/16758 |
long_lat |
ENVELOPE(32.417,32.417,67.133,67.133) ENVELOPE(32.861,32.861,66.679,66.679) |
geographic |
White Sea Kandalaksha Kovda |
geographic_facet |
White Sea Kandalaksha Kovda |
genre |
Fennoscandian White Sea Lapland |
genre_facet |
Fennoscandian White Sea Lapland |
op_relation |
Vestnik of St Petersburg University. Earth Sciences;Volume 64; Issue 3 Nikolaeva S. B. (2019). Postglacial tectonics and palaeoseisic dislocation in the Kovda area (Kandalaksha Bay, eastern Fennoscandian Shield). Vestnik of Saint Petersburg University. Earth Sciences, 64 (3), 434–453. https://doi.org/10.21638/spbu07.2019.304 http://hdl.handle.net/11701/16758 |
op_doi |
https://doi.org/10.21638/spbu07.2019.304 |
container_title |
Vestnik of Saint Petersburg University. Earth Sciences |
container_volume |
64 |
container_issue |
3 |
container_start_page |
434 |
op_container_end_page |
453 |
_version_ |
1765998499183198208 |