HEAT FLOW AND SEISMICITY WITHIN WESTERN PART OF THE EAST EUROPEAN PLATFORM. Zui, V.I., Boborykin, A.M., Urban, G.I. and Zhuk, M.S. Institute of Geological Sciences. Academy of Sciences of Belarus

The territory of Belarus, the Baltic Republics and adjacent areas have similar geologic evolution. More than 350 heat flow density values are ava-ilable within this area. They range from as low as 10-12 to over 90 mW/m2. Low heat flow density below 40 mW/ml is typical for the main Precambrian tectonic units: Orsha Depression, Mazury-Belarussian Anteclise, Polessian Saddle, the northern slope of the Ukrainian Shield. The Palaeozoic tectonic units: Pripyat and Podlyaska-Brest Depressions, Moscow Syneclise, as well as the south-eastern slope of the Baltic Shield and the central part of the Baltic Syneclise, exhibit increased heat flow above 45-50 mW/mI. High values over 70 mW/ml were observed only within the northern part of the Pripyat Depression and the West-Lithuanian Massif.

Seismic stations were recently created mainly in Belarus. More than a dozen of weak seismic events per year were detected instrumentally within the north-western part of the Pripyat Depression and adjoining areas of the Mazury-Belarussian Anteclise. Data on a number of historic earthquakes were collected for territories of Belarus, Latvia and Estonia. According to the available information, some of them caused damage to buildings and produced cracks on the ground surface.
Both local and distant earthquakes influence the seismicity of the region. The highest earthquake intensities were about 7 for historic events. Their typical values are below 5 according to observation results within the Soligorsk town area. The foci of the last ones are within the crust. Main elements generating seismicity are active rupture zones of the Baltic Sea and the Gulf of Finland floors, Pripyat-Dnieper-Donets Aulacogen, the suture zone of the Precambrian East European and Palaeozoic Central European Platforms, a junction zone between the Baltic Shield and Russian Plate, as well as the Carpathians.

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