Paleoseismodeformations of hard rocks in the Karelian isthmus

Within the limits of the Fennoscandian (Baltic) crystalline shield, late and postglacial shattering of hard rocks due to strong ancient seismic effects has been studied at several sites. The approach of these studies implied the search for evidence of a seismic origin of dislocations and, in some cases, determination of the dislocation age. These studies have also been carried out by the authors in southern Karelia and northern Leningrad oblast. The present work is devoted to elaboration of criteria and distinguishing of several coeval events, and to parameterization of these events in terms of seismology standards. This communication presents the first, basic part of such a study. The source parameters were defined on the basis of models and calculations from the initial values of displacements for each of the distinguished events.