Оценка эффективности системы заводнения турнейско-фаменской залежи Маговского месторождения

Abstract

Waterflooding effectiveness of the structurally complex carbonate reservoir in the Tournaisian-Famennian formation of the Magovskoye field is studied. This formation is characterised with hardened geological conditions, which affects the development efficiency. The work includes analysis of the history and current state of the formation development, production and injection well performance, the reservoir natural energy contents, the reservoir pressure performance across wells, formation geology and lithofacies structure. A correlation was established between the well performance and lithofacies heterogeneity of the formation. A combination of boundary and marginal flooding systems is arranged at the formation target, which shows low efficiency. The wells located in the edge reservoir areas exhibit low reservoir pressures; these areas feature low reservoir properties. Concurrently, there is a difference between the upper and lower parts of the section. The wells drilled into the lower part of the section show a positive water production performance and positive energy level, which is associated with the aquifer influence. The wells drilled into the upper part of the section show lower reservoir properties, higher compartmentalisation and no aquifer influence. The wells located in the areas with low reservoir pressures were reviewed, the reasons for the depleted content of energy were identified and research proposals were provided. Furthermore, we considered the well intervention operations performed at the formation in question and at formations of similar fields in the corresponding geological field conditions, and identified operations with the highest technological effects. As a result of the studies, well intervention operations were proposed, subject to the specific structure of the lithofacies zones and the nature of the relationship between production and injection wells. It will result in enhancing the waterflood system effectiveness and affecting the target development efficiency, in general.