НЕОТЕКТОНИЧЕСКИЙ ПРОГНОЗ РАЗВИТИЯ ВИСЛИНСКОЙ КОСЫ БАЛТИЙСКОГО МОРЯ

Abstract

Any prediction relies on the accepted starting positions. At present with regard to coastal accumulative forms the forecast of their development is usually based on the ideas of increasing the sea level and stocks of the corresponding material. But in regional geosystems neotectonic conditions are an important and often a determining factor. The study of neotectonics of any territory is more productive if its location is considered taking into account the historical evolution and the general geological and geographic situation of the corresponding region. This fully applies to the area location of the Vistula Spit. Geotectonically it is confined to the southeastern wing of the Gdańsk depression, which complicates large hemisyneclise, in the bed of which the Baltic Sea water area was formed as the last stage of the Valdai glaciation receded and subsequently merged with the World Ocean. During the transgression a chain of alongs horebars were formed, that gave rise to the Vistula barrier beach. In connection with the construction of the Baltic (Pillaus) canal the fragment of the transplant located to the north of it is represented by the Pillaus peninsula and its largest southern part functions as Spit. As a result of the performed studies a cartographic model of the neotectonics of the investigated region is drawn up, where the block structure is shown, within which the Vistula Spit was formed. The forecast of its development in this study is based on an analysis of the structural-tectonic environment and the Holocene kinematics of sea level. It is shown that the eustatic factor will not have a noticeable effect on the evolution of the Spit, at least on the engineering (50-60 years) time scale. There are no catastrophic changes in the development of the coastal part of this accumulative form in almost all its extent during this time, as coastal morphogenesis has adapted to the current situation. An exception is the  its distal part by the canal, where the erosion of the shore can be stopped by the implementation of engineering solutions. In the long term we can expect the collapse of the Kaliningrad Gulf into a number of lakes due to the filling of sediments and a weak tectonic uplift of the territory. Assessing the natural environment of the area we can say that the development of the Vistula Spit gives cause for concern, but not for panic.