Formation of sedimentation cycles of coal deposits in the Eastern Donbas

The mining industry needs reliable information about the geological structure of a region, genesis and patterns of location of coal strata, as well as the thickness and structure of coal beds. With such data, the risk is minimized and the rationality of the work is improved. The results can be formulated as follows. Coal seams are often represented by three layers. The middle layer is ubiquitous and has the highest thickness. The thickness and the structure of the formations change in a sudden manner and are governed by changes in stratigraphic volume and processes of superimposition. Coal seams are monocyclic (each delta cycle ends with the formation of a coal seam). Coalfields consist of two or more closespaced, but not merged, stratigraphically adjacent beds. The occurrence and structure of coalfields are conditioned by changes in the beds and clastic interbeds. The formation of coal seams, cyclites and deposits took place in the dead river deltas during settling and sedimentation, and was controlled by the compensation surface. The presence or absence of a deposit in the coal-bearing strata is governed by the type of a delta. In branched deltas, no convergence of coal seams can occur. In a delta with branching towards the sea, isometric deposits form, and their sizes decrease towards the sea. In single-course deltas, large deposits form. No splitting of coal seams and cyclites in the Eastern Donbas is found. Genetic differences between coal seams and deposits condition different behavior of these objects in unprospected areas.The article was prepared within the framework of the state contract with the Southern Scientific Center RAS, Project No. 122020100352-6.The study used the equipment of the Shared Scientific and Technological Equipment Center at SSC RAS (Analysis, Development, Validation).