The Domanicoid high-carbon formation, represented by the alternation of clay-siliceous-carbonate rocks with an increased content of organic matter, covers the stratigraphic interval from the Sargayev horizon of the Upper Devonian to the lower Tournaisian stage of the Lower Carboniferous and is widespread in the east of the East European platform. The article presents the results of seismostratigraphic and cyclostratigraphic analyzes, based on the outcome thereof a regional geological model of the formation of the Domanicoid complex was developed. In the structure of the Middle Frasnian-Tournaisian Domanicoid deposits, three distinct areas were identified, differing in composition, structure, thickness and formation conditions, namely a carbonate platform, slopes, and an intrashelf depression. The revealed cyclicity in the structure of the studied complex implied that the section consisted of 4 large cyclites of the second order, the accumulation of which occurred at the stage of sea level rise on the background of general regression. Analysis of the material composition of the sediments made it possible to identify different sedimentation environments and typical sections of these areas within each cycle. The sides of the depression are composed of limestones of the shallow-water shelf, and the slopes are an alternation of detrital limestones, clayey limestones, and mixed siliceous-carbonate and carbonate-siliceous rocks. The deep-sea basin (intrashelf depression) is characterized by uncompensated sedimentation of mixed siliceous-carbonate and carbonate-siliceous rocks, with a high organic matter content (average content over 2.5 %), with which an area of Domanicoid high-carbon formation prospects is associated. The zones of the predominant development of these deposits, ranked according to the degree of prospects, have been determined. The zone of high prospects has the total thickness of high-carbon siliceous-carbonate and carbonate-siliceous rocks reaches 90–140 m and is mainly distributed in the central part of the trough.
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