NATURAL FEATURES AND HYPOTHESES OF ORIGIN NEASHORE BARS IN THE COASTAL ZONE OF NON-TIDAL SEAS

Abstract

Problems of the research. The article considers the origin, morphology and dynamics of unique forms of coastal-marine relief in the coastal zone of non-tidal seas, under the influence of the hydrogen factor, an exceptionally strong potential of mechanical energy, sufficiently large reserves of sand deposits (fractions of 0.05–1.00 mm), active influence of wave impulses and wave currents in the zone of energy dissipation, active nanoexchange between the shore and the underwater slope. It is shown that this issue has a long history of scientific research in different countries due to its important practical significance. Long years we researching the alongshore sand drifting between C. Bol. Fontain in North to Jebriyan Bay in South as a experimental natural object of the North-Western part of the Black Sea. Theoretical elaborations and methods. Among the natural features of the named landforms, the researchers distinguish 8 leading ones, which are manifested only in the environment of the coastal zone. Therefore, the purpose of the article is to consider the genetic hypotheses of the formation of underwater sand bars in the coastal zone of the seas over the past 100 years, and on this basis – to outline, evaluate, analyze several hypotheses about the formation of bars, show their positives and disadvantages, name the genetic features for the physical geographical. coastal environments As part of the eight most important and most common features, we have identified the following: distribution of wind wave sizes and wave current velocities; the value of the steepness of the underwater slope covered with sediments; value of sediment sizes and hydraulic value of coastal zone sediments; some processes of wave transformation and dispersion of wave energy; certain individual processes of sediment movement of different hydraulic magnitudes in a cell of a sandy coastal zone; steepness of wind waves during storms in the spray source; active action of sand drifts by movement along the coastline and under the influence of the regime of transverse sediments; the nature of underwater swells is different, because one of them moves from the underwater slope to the shore, another – from the shore towards the sea, and the third is dynamically stable. Main results and conclusions. As can be seen, the main hypotheses and the corresponding features of the formation of underwater swells act on their own, separately from the general process of development of the coastal zone of the seas. Such a principle does not meet the elementary requirements for the definition and evaluation of complex geographic natural systems. This is especially true for the coastal zone of the seas, where all the genetic components of the continental, oceanic, and coastal-marine types interact closely in a complex. They act unanimously. It is from such positions, according to this principle, that underwater sand bars and other coastal-marine landforms should be investigated. In other elements of the exogenous part of the geographic envelope, they are not found anywhere and determine the uniqueness of the coastal zone of the seas. The authors of these variants build their hypotheses on separate parts of natural coastal phenomena. Until now, researchers have avoided complex, systematic approaches to this topic. Therefore, the article provides recommendations for improving the theory of the genesis and development of underwater swells within different sites of alongshore sand drifting.