THE GEOMORPHOLOGICAL INDICATIONS OF HORIZONTAL NEOTECTONIC MOVEMENTS ALONG THE BOUNDARY BETWEEN BALTIC SHIELD AND WEST-ARCTIC PLATFORM (MURMANSK REGION)

Abstract

Horizontal component of neotectonic movements in platform conditions can be identified by comparing the morphostructural pattern of the region with the known structural models of horizontal deformations. Through the juncture of the Baltic shield and Barents plate, which is the part of the Western Arctic platform the two sutures pass: Karpinsky lineament – latitudinal zone of discontinuities, by which crystalline basement is dipping step by step seaward and thrust-shear structure Trollfjord–Rybachiy–Kanin. Characteristic features for this area are as follows: concentration of cracks, bearing tectonic mirrors and furrows slip, faults and near-fault deformations, manifested by the valleys and canyons, and the steps of relief, the formation of which cannot be explained by selective denudation of the substrate. The epicenters of earthquakes are numerous here. By the geological data the morphostructures were distinguished here with the indications of rotations of blocks, leading to the subsidences in the areas of stretching and shears along an echelon faults and also movements in mutually antithetic directions – right and left strike-slips of unknown age. Antithetic movements along the plate boundaries can be explained by the complex nature of the interaction of the East European platform with its frame.