During the large-scale hydraulic fracturing of thin interbedded sandstone reservoir (short for TISR), the fracture is propagated greatly along the fracture height direction, leading the length/height ratio of fracture usually smaller than 4. Because the interlayer is thin and weak, this can not afford strong restrictions on the height of fracture propagations. In this condition, the traditional pseudo-3D model only considering the fluid flowing along the length direction of fracture does not agree with the actual situation. In this study, a new pseudo-3D model of predicting the fracture development with 2D flow is built up according to the hydraulic fracturing characteristics of TISR. In the new model, the flow along the fracture height direction is considered. The precise solutions of fracture length and height dimensions are calculated by the new model. The numerical calculating software is obtained based on the new model, which is used to stimulate the fracture development during hydraulic fracturing in TISR. The results show that the new model has a perfect performance in analyzing the fracture development during large-scale hydraulic fracturing in TISR.
Stimulation of TISR by massive hydraulic fracturing has been established as a very successful technology for improving the petroleum production performance (XU Yun1ong et al., 2005; Dou Ranglin et al, 2001). In the TISR, interbeds and storage layers appear by alternation and their strengths are weak, leading a weak constrain to the fracture propagation in height direction. So, during massive hydraulic fracturing, the fracture propagates effectively in vertical and horizontal directions. These 3D and pseudo-3D are suitable in casing of fractures length/height >4, illegal for the TISR hydraulic fracturing calculating for the fracture propagation in height direction effectively. The length/height of TISR hydraulic fracturing is usual smaller than 4.