Geological Survey of Finland, Special Paper 46 - arkisto.gsf.fi

Applied Quaternary research in the central part of glaciated terrain,
edited by Peter Johansson and Pertti Sarala.
Geological Survey of Finland, Special Paper 46, 129–134, 2007.
GEOLOGICAL EVIDENCE OF THE SEISMICITY IN THE KOLA
REGION DURING THE LATE PLEISTOCENE AND HOLOCENE
by
Vladimir Yevzerov and Svetlana Nikolaeva 1
Yevzerov, V. & Nikolaeva, S. 2007. Geological evidence of the
seismicity in the Kola region during the Late Pleistocene and
Holocene. Applied Quaternary research in the central part of glaciated
terrain. Geological Survey of Finland, Special Paper 46,
129–134, 2 fi gures.
Deglaciation of the Kola region during the Late Valdaian
(Weichselian) occurred mainly by separation of the vast ice
peripheral covers from the active ice massif and the subsequent
melt of dead ice. After last ice advance in the Younger Dryas,
the ice sheet was dissected by extended marine gulfs during the
beginning of the Holocene and quickly melted. The ice had the
highest surface gradient in the Older Dryas and deglaciation was
fastest in the area that was covered by the Younger Dryas ice.
Glacioisostatic uplift of the Kola region in the western part of the
Kola Peninsula was more intensive compared to the eastern part.
Such a tendency prevailed during the end of the Late Pleistocene
and Holocene. At the same time, the speed of glacioisostatic uplift
decreased everywhere in time, but the uplift proceeds even at
present.
Palaeoseismic dislocations studied using geologic-geomorphologic
methods are expressed in the topography in the form of
seismic ditches, scarps, gorges, fractures in crystalline rocks and
disturbances in the Quaternary sediment units. Epicentres of the
ancient earthquakes basically coincide with epicentres of modern
earthquakes and are concentrated on territory that was covered
by active ice with the greatest gradient of its surface during the
Older Dryas and, which elevated most intensively after deglaciation
of the area. All the data assumes that the main reason for the
seismicity of the region is a tension that was caused the glacioisostatic
uplift during and after deglaciation.
Key words (GeoRef Thesaurus, AGI): glacial geology, deglaciation,
neotectonics, glacial rebound, seismicity, Holocene, Pleistocene,
Kola Peninsula, Russian Federation.
1 Geological Institute of Kola Science Centre, 184209 Apatity,
Fersman str., 14, Russia
E-mail: yevzerov@geoksc.apatity.ru,
nikolaeva@geoksc.apatity.ru
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