The White Sea Coasts within the Fennoscandian Crystal Shield in the Pleistocene and Holocene
The article presents the main results on the stratigraphy and geochronology of Quaternary sediments, as well as data on neotectonics, seismicity and the movement of the coastline of the White Sea obtained in recent decades by geological-geomorphological, biostratigraphic, paleoseismological methods,...
| Main Authors: | , |
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| Other Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | Russian |
| Published: |
Izvestiya Rossiiskoi Akademii Nauk. Seriya Geograficheskaya
2023
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| Online Access: | https://izvestia.igras.ru/jour/article/view/1665 https://doi.org/10.31857/S258755662206005X |
| Summary: | The article presents the main results on the stratigraphy and geochronology of Quaternary sediments, as well as data on neotectonics, seismicity and the movement of the coastline of the White Sea obtained in recent decades by geological-geomorphological, biostratigraphic, paleoseismological methods, numerical dating methods and allowing us to present a paleogeographical model of the Kola-Karelian region. The lack of one for the White Sea coastal area located within the Fennoscandian Shield caused the relevance of the presented synthesis. Interglacial marine and glacial deposits of the Middle and Late Pleistocene and Holocene were identified. Only the sediments of the Last Glacier and its meltwater, as well as Postglacial marine and aeolian deposits in some places, are of landform-forming importance. During the last glaciation, the marine regime in the White Sea basin was interrupted. Extensive freshwater lakes appeared in the White Sea basin due to glacial meltwaters during the deglaciation. These proglacial lakes became brackish-water in the Allerod as Atlantic waters entered. In contrast to earlier study, only two marine transgressions have been identified here, which took place at the Late Glacial–onset of the Holocene and at the late Early Holocene–early Middle Holocene. The Kandalakshsky and Tersky Coasts of the White Sea are characterized throughout the Holocene by a different-amplitude glacioisostatic and tectonic uplift, especially active in the western part of the Kandalakshsky Coast. Within the Karelian Coast, in the last 4000 years tectonic block, rather than domeshaped glacioisostatic uplift of the Earth’s crust prevails. Due to the glacial rebound, strong earthquakes occurred on the coasts of the White Sea, which were manifested by visible deformations of the continuity of rocks and deposits. In the eastern Fennoscandian Shield, the most tectonically active part is the coastal areas of the Kandalaksha Bay. The stress and relaxation of the Earth’s crust during the Last Glaciations, along with the ... |
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