Analytical model of fracture propagation in carbonate reservoirs

Abstract

The fracture propagation length and propagation angle can be calculated quickly using the fracture propagation analytical model. But for fractured-vuggy carbonate reservoirs, the addition of a discontinuous medium in the analytical model makes it difficult to obtain accurate results via calculation. In this paper, an analytical solution model for fracture propagation in carbonate reservoirs is established. On the premise of ensuring calculation accuracy, the discontinuous displacement algorithm is used to introduce the fracture and hole characteristics into the calculation. The model comprehensively considers the interference of in-situ stress, fracture tip stress, and stress field of fractures and holes on fracture propagation. The calculation accuracy of the model in a fractured-vuggy carbonate reservoir is verified by a true triaxial fracturing physical simulation experiment. The model can be used for subsequent research on the fracture propagation law of carbonate reservoirs containing discontinuous bodies, such as fractures and caves.