Differentiation of Rudov Beds based on the statistical methods on geological and geophysical data

Abstract

Purpose. To perform the lithological-facies dismemberment of the Rudov Beds using geological and well-logging data to clarify the formation genesis of the hydrocarbon sources deposits within the Yablunivska structure of the Dnieper-Donets basin. Methodology. Cluster and factor analysis methods were used as well as Q.Passys method of well logging data interpretation for estimating the content of organic carbon (TOC). Findings. Regularities of geological structure, lithological heterogeneities, distribution of separate lithotypes and content of organic carbon in the Rudov Beds within Yablunivske oil and gas condensate field are established. The spatial distribution of separate facies types of rocks, thicknesses of their radioactivity layers and content of organic carbon (organic matter) within a single structure of the Dnieper-Donets depression is studied. Originality. For the first time according to geophysical data with the use of statistical methods, the lithological-facies dismemberment of the petroleum bearing strata, which have a regional distribution within the Dnieper-Donetsk basin, has been performed. It is found that there is no close correlation between natural radioactivity and the content of organic carbon in the Rudov Beds of the Lower Carboniferous. Certain conclusions have been made concerning the confirmation of the hypothesis about the formation of the Rudov beds in the conditions of shallow water desalinated sea gulf. Practical value. The proposed approach to lithological-facies dismemberment of the Rudov Beds by the well-logging data allows clarifying conditions for petroleum bearing stratum formation in order to assess its real oil and gas generation potential.