Impact estimation of geomechanical effects on fields development in various conditions

The paper presents a summary of the experience of using geomechanical modeling to solve problems of field development in terms of studying and reproducing actual events at wells associated with early flooding of deposits due to the failure of the reservoir and shale breaks. The method of estimating changes in elasticstrength properties is considered on the core for various types of reservoirs in Western and Eastern Siberia when changing the saturating fluid to water. The developed modeling graph, taking into account the influence of changes in the elastic-strength properties of rocks from changes in saturation on the destruction of the reservoir and the appearance of highly conductive channels, is applied to gas and oil deposits. The results obtained indicate the relevance of conducting such studies to predict possible negative geomechanical effects on deposits prone to the formation of highly conductive channels from the aquifer or injection wells flooding.

The aim. Study of negative geomechanical effects associated with early flooding of producing wells due to the destruction of the reservoir and shale breaks. Materials and methods. Based on the analysis of available modeling approaches and standard data sets used for geomechanical modeling, calibration methods, an algorithm for reproducing geomechanical effects associated with changes in the elastic-strength properties of rocks from saturation has been developed and tested, which allows taking into account the effect of rock failure on permeability.

Results. According to the results of the conducted studies, it was possible to show the formation of negative geomechanical effects on wells (premature water breakthroughs and the waterflooding from the aquifer).

Conclusion. At different initial core base saturations, studies of changes in the elastic-strength properties of rocks with a change in saturation have been carried out. Studies have shown a significant (up to 10 times) weakening of strength properties in unconsolidated formations when changing natural saturation to water. The created methodology for studying filtration-significant geomechanical effects is used to confirm the actual events at wells associated with the formation of highly conductive channels.

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