State of the coasts and exogenous geological processes between cape Konstantinovskiy and cape Vinogradniy on the SOUTH-WESTERN coast of Crimea
Intensive development of the Crimean coast intensifies the growth in the frequency of occurrence of adverse exogenous geological processes on Sevastopol coasts. The aim of the article is to consider the current state of coasts and the development of exogenous geological processes between capes Konstantinovsky and Vinogradny. The initial materials were: published works; funds of the Institute of mineral resources, Crimean hydrogeological expedition and GGP "Krymgeology"; cartographic sources; resource Google earth; field studies of the author. During the field work methods of observation, instrumental and semi-instrumental measurements at key sites, photometods were used. Methods of analysis and synthesis, comparative-geographical, comparative-historical were used for information processing. The region between cape Konstantinovsky and cape Chersonesos includes ingression bays and open abrasive coasts. A significant part of bay coasts are anthropogenic (man-made) coasts and, practically, they do not change at the present time. The height of coasts is grow from cape Chersonesos. To the northeast near cape Konstantinovsky the coasts heigh is 7.3 m, to southeast near cape Vinogradniy they height is 77 m. The speed of tectonic subsidence is varied from 0.5 to 3 mm·year<sup>-1</sup>. They are developed in Neogene limestones and classified as abrasion resistant. During movement from capes to top of bays, the limestones are replaced by clays and loose quaternary marine sediments. The coastline between cape Konstantinovsky and cape Chersonesos is divided into about 30 bays, the largest of which are Sevastopol, South, Quarantine, Streleckaya, Kruglaya, Kamishovaya and Kosachiya. At the tops of the bays the beaches of an average width of 10-15 m are formed. They have a complex feeding, but due to the lack of debris their artificial recharge is carried out. As a result the width, material and granulometric composition of the coasts has been significantly changed. On the open coasts the beaches “pocket” type have a width of 3-7 m. Abrasive, landslide, landslim, talus processes and karst are active mainly on open coasts and capes. The speed of coastal processes, according to different data, is vary from 0-0.01 to 0.05-0.25 m·year-1 (maximum 0.5 m·year-1). The banks retreat in Quarantine, Pesochnaya, Streleckaya, Kruglaya and Kazatchiya bays. While the coast recede, the development and implementation of the complex of coastal protection acts is necessary. They firstly should be realized on the ancient settlement Chersonesos Taurica and the Eastern shore of Quarantine bay. The selection of coastal protection concept first of all should be guided by the principle of geonics, which involves the maximum compliance of the methods and elements of hydraulic structures to natural processes and objects, and is aimed to preserving the natural appearance of coastal landscapes. An important measure of stabilization of coastal processes is the control of all types of management within the five-hundred-meter marine water protection zone.