On the depth of identification of objects in the study of the influence of the density of the grid of wells on the degree of production of oil reserves

The article studies the effect of the well grid density on the final oil recovery coefficient under conditions of various groups of objects in carbonate reservoirs of the Volga-Ural oil and gas province. The issue being solved within the framework of this work is one of the most relevant and important when making various management decisions in conditions of uncertainty, significant variability and heterogeneity of geological and field data. More than 500 deposits of carbonate reservoirs were selected for the study, the development of which is carried out on the territory of the Ural-Volga region. To implement an integrated approach, the construction of models was carried out in several interrelated stages. Within the framework of basic modeling, field statistical methods were used to identify dependencies describing at a high quantitative and qualitative level the relationship between the oil recovery coefficient and the density of the well grid before flooding. To obtain the most representative results, a separate approach based on the preliminary division of objects into groups was also used. At the second stage, in addition, a deep differentiation of the initial objects was implemented to determine hidden patterns within already formed groups and a similar construction of models according to which interpretation was performed. When combining the results obtained, it was reliably established that models for assessing the degree of reserve production from the density of the well grid should be built not only in general by tectonic and stratigraphic elements, but also differentially by groups identified as a result of in-depth identification of development sites. It is proposed to use the obtained dependencies to solve the problems of optimizing the density of the well grid for both long-term oil deposits under development and newly commissioned and at the stage of drafting the first design documents. Keywords: well grid density; oil recovery coefficient; modeling; grouping of deposits of the Volga-Ural oil and gas province; deep identification of objects; carbonate reservoirs.