The role and significance of geological heterogeneity in the formation of limestone productivity in the Famennian stage of the South Tatar arch

The purpose of the research is to identify the degree and nature of the geological heterogeneity impact on deposit productivity in order to use the obtained patterns in solving fundamental problems of oil field development considering different density of geological and field information and drastically uneven data of well operation. The object of the study is the Famennian stage deposits of the South Tatar arch located within the Volga-Ural oil and gas province. The use of the elements of multidimensional regression modeling allowed to obtain the dependences of deposit productivity on the number of geological and field parameters resulting in the establishment of the following features: the degree of parameters influence on productivity varies in the conditions of selected groups of identical objects; there are some cases featuring the different nature of parameter influence, which proves the relevance and necessity of implementing differentiation procedures when making a forecast in order to reduce the risks of making ineffective management decisions. The presented results can be used for reasonable estimation of deposit capacity at the stage of their commissioning. Since the error of the presented models is a quarter higher than the one of the models including the indicators of geological heterogeneity, it is quite reasonable to use them for drafting the first project documents as they allow subsoil users to successfully formulate an optimal approach to the implementation of an effective field development system.