Characteristic of the lithosphire of the sedimentary basins of Europe by the regional gravity modeling data
© Yegorova T.O.
A three - dimensional (3D) crustal density model approximated by two regional layers of
variable thickness - the sedimentary cover and the crystalline crust - has been constructed in
one degree averaging for the whole European continent. Inside the model layers a lateral
variation of average density, depending on the type of geological structure, is assumed.
Offshore a sea-water layer was added into the model. The model is based on the generalized
velocity model represented by structure maps for the main seismic horizons - the "seismic"
basement and the Moho boundary. The gravity effect of the model layers as well as total effect of the
crust were calculated. Residual gravity anomalies, obtained by subtracting the crustal effect from the
observed field, are caused by density heterogeneities of the uppermost mantle. These anomalies are
shown to correlate with upper mantle heterogeneities revealed, from both seismology and geothermal data. Considering the type and magnitude of mantle anomaly, the type of isostatic compensation,
specific features of the evolution the and type of assumed endogenic regime, the following
classification of the sedimentary basins in Europe is proposed. 1) Deep sedimentary basins located
on the East-European platform and its northern and eastern margins (Peri-Caspian, Dnieper-Donets, Barents Sea basins, Fore-Ural trough) with no significant mantle anomalies; 2) basins of active
taphrogenic and rift regimes, which laid on the activated thin crust of the Western Europe and
Mediterranean, with negative mantle anomalies of - 150÷200 mGal; 3) basins associated with suture
zones at the western and southern margins of the East-European platform (Polish trough, South-Caspian Depression) and characterized by positive mantle anomalies of 50÷150 mGal. An
analysis of the isostatic compensation of the main types of the sedimentary basins in Europe has been
carried out.
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