Geotraverse «Granite—Odesa—Kryvyi Rih—Pereschepine

Abstract

The article examines the results of research carried out by the methods of reflected waves and common depth point (MRW-CDP) on the «Granit» geotraverse, which crosses the whole of Ukraine from the southwest to the northeast and passes through the territories of Odesa, Mykolaiv, Dnipropetrovsk, and Kharkiv regions, west of Belgorod region of Russia. In structural and tectonic terms, the geotraverse crosses large geological structures: the marginal part of the Scythian Plate (SP), the Ukrainian Shield (USH), the Dnieper-Donetsk Basin (DDB) and the southern slope of the Voronezh Crystalline Massif (VCM). The analysis of the features of the registered wave field and the completed structural constructions of the consolidated crust and upper mantle in the section of the «Granite» geotraverse shows a complex heterogeneous structure with certain spatially correlated regularities, against the background of which there are numerous inhomogeneities characteristic of both individual blocks and their individual intervals. The cross-sections of all the studied geostructures are characterized by a high level of saturation with non-extended, unevenly distributed reflective elements, which occupy positions from subhorizontal to steeply sloping in space. With all the diversity of the mutual location of both individual boundaries and their groups, a fairly strict correlation is established, which primarily provides information about the nature of stratification, deformations, and the stress state of the structures of the consolidated crust and upper mantle. In the modern structure of the crust, a significant role belongs to faults and tectonic plates, the vast majority of which are manifested as inclined zonal bodies with different orientations. Systems of faults and plates form a complex hierarchical interdependence. The «crust-mantle» transition zone is a complex, laterally variable area, with a thickness of 3 to 7 km, caused by systems of subhorizontal stratification, expressed by the concentration of reflective elements. The largest homogeneous and contrasting region of the transition is manifested in the structures of ancient consolidation, with a thickness of the crust of about 40 km. As a result of the research, more detailed information on the structure of individual tectonic elements was obtained, and some general principles of the structure of the transition zone from the ancient continental platform to the active folded belt were clarified.