On rock deformation during hydraulic fracturing in horizontal wells

Abstract

The article studies problems of rock deformation during the hydraulic fracturing in horizontal wells. The schemes show stresses acting on the rock during the fracturing. The article analyzes the Prats equation showing that powerful deformation processes can occur during fracturing operations in tectonically active areas. Schemes of deformation processes during the multi-stage hydraulic fracturing and formation fluid selection are presented. The rock mass above the reservoir between the cracks in the unperturbed part is held in zones with initial reservoir pressure (reference zones). The sizes of these zones decrease with an increase in the sizes of the well drainage zones and become destroyed. When the drainage areas are closed, the rock mass moves over the reservoir between the cracks. An increase in the number of hydraulic fracturing stages and a decrease in the distance between fractures can cause seismic manifestations during hydrocarbon production, especially in tectonically active areas.