THE SIGNIFICANCE OF THE PLEISTOCENE AQUATIC FAUNA OF MOLLUSKS FOR THE REPRODUCTION OF SEDIMENTATION CONDITIONS IN WESTERN UKRAINE

Abstract

The territory of Western Ukraine is characterized by the development of a wide range of genetic types of continental formations. The Carpathian Mountain Country (properly the Carpathians, East Carpathian Foreland, and Transcarpathia) and the highly fragmented parts of the Volhynia and Podolia Uplands are characterized by a special diversity. The time range of their formation is vast – from the Early Pleistocene to the present. The complexity of the structure of the Quaternary sequence gives rise to discussions about the origin of some components of anthropogenic accumulations. Despite the fact that most of the challenging issues have already been resolved, we find debatable information in the works of some researchers of the 20th and even the 21st centuries about the aqueous origin of the thick sequences of anthropogenic sediments covering the terraces of the Dniester and Dnieper basins. The researchers use many methods to solve the issue of the deposit genesis. Some of them are based on the study of paleontological (including paleomalacological) remains, which are often found in both aqueous (alluvial, lake, swamp) and aerial (primarily loess) formations. Malacofauna has been used since the second half of the 19th century to determine the age, conditions of formation, and origin of the deposits. To establish the origin of sediments we have used the mollusk fauna in this work, which can be often found in the formations of the studied territory. The interpretation of the fauna is debatable in the sections where several genetic types of formations are exposed, primarily alluvial and eolian–deluvial loess. This type of combination of deposits is found in outcrops on the numerous terraces of the Dniester and the terraces of its East Carpathian Foreland’s and Podolia tributaries. The results of the research obtained by us using paleomalacological studies correlate well with data obtained using other methods. Such methods include actual field observations, as well as lithological, palaeopedological, paleontological (study of fossil mammals, fish, spores, and pollen), archaeological, and other methods. The results presented in this work made it possible to establish the genesis of some components of polygenetic complex strata, as well as testify to the effectiveness of the applied research method. Keywords: anthropogen; malacofauna; alluvium; loess; paleogeography; Podolia; East Carpathian Foreland.