Large-scale volume fracturing is currently a key technique for efficient development of shale oil reser-voirs,and how to describe and characterize complex fracture network formed by volume fracturing and to further un-derstand flowback characteristics after fracturing are urgent challenges in shale oil reservoir development.In view of characterization problem of flowback after fracturing in shale oil reservoir,the influence of reservoir property and complex fracture geometry on flowback characteristics after fracturing is quantitatively evaluated by considering fracture opening-closure characteristics during the process of fracturing fluid injection and flowback,as well as non-linear flow characteristics of the matrix.The results show that 3D complex fracture network can be characterized by the coordinates of fracture center point,fracture dip,fracture azimuth and boundary shape,and connected fracture network can be generated by stochastic simulation and connectivity identification.Meanwhile,considering fracture opening-closure characteristics is the key to achieving effective simulation of whole process of fracturing fluid injec-tion-flowback,the impact of isolated natural fractures on flowback characteristics after fracturing can be ignored,and the variation of fracture geometry also has obvious impact on performance of flowback after fracturing.The re-search can better characterize the flowback mechanism of fluids in complex fracture networks after fracturing,and can be applied in development performance simulation of volume fractured shale oil reservoirs.
关键词
页岩油藏/体积压裂/复杂缝网/裂缝张开-闭合机理/压裂后返排
Key words
shale oil reservoir/volume fracturing/complex fracture network/fracture opening-closure mecha-nism/flowback after fracturing
维普
万方数据