Systematics and typology of the relief forms of the Oleshkivski Sands

Oleshkivski Sands is one of the most peculiar regions of psammomorphic land- scapes in Europe and in particular the ancient delta region of the Left Bank of the Lower Dnipro. The territory of the sands consists of seven hilly sand massifs and six inter-arenial flat-level geocomplexes. The relief and peculiarities of the formation of this territory are still insufficiently studied, the relief of the intra-arenial landscapes is almost completely unexplored. The objectives of this study were sys- tematics and typology of the relief forms with approaches to elucidating the factors and mechanism of formation of geomorphological formations of Oleshkivski Sands. The methods of research of the relief of the Oleshkivski Sands were based on existing experience in identification, mapping, classification, analysis of sandy landforms, deciphering their portrayal on satellite images, as well as on many years of field research by the author. The generalized and systematized analysis of the relief, illustrated with maps, tables and photo- graphic materials, allowed us to form the systematics of the microforms of the relief and the typology of the mesorelief of the Olesh- kivski Sands. The results of such studies have revealled the morphological and genetic diversity of individual landforms within the arenas and inter-arenial geocomplexes, and a total of seven arenas of the Oleshkivski Sands, and respectively the complicated history of the formation of the region. Of the arenial geocomplexes, the hilly massifs and intra-arenial depressions were considered separately. Among the hilly massifs, the dominant were found to be hilly and undulated chaotically-configured structures, at some places with the distribution of parabolic dunes and dune ridges, and also the subordinate spread of the mound massifs. The morphological and genetic diversity of inter-arenial depressions was determined, which can be considered as diagnostic objects in the formation of the Oleshkivski Sands. The analysis of the relief of the territory of the Oleshkivski Sands revealed that different factors were in operation at different time stages of its formation – fluvial (fluvioglacial), aeolian, suffusion-subsidence, thalassogenic, anthropogenic. Аt the present stage the dominant are aeolian and anthropogenic factors. Special attention was paid to parallel hilly ridges of the Kinburnska and Kelegeiska arenas, considered in the context of the diluvial (catafluvial) paradigm as a manifestation of giant ripples. The discreetly formed parallel ridges and extended hollows of the Kinburn Peninsula are presented in the context of flood-freshet events in the history of the function- ing of the Dnipro and the Southern Bug, in places where water masses flow through watershed geocomplexes.