Shale Reservoir Fracturing Technology

Because shale gas reservoirs have lower permeability than tight gas and it is difficult for the gas to flow into the wellbore without technological measures, the concept of shale gas reservoir modification is completely different from that of conventional oil and gas, which requires the reservoir to be completely broken up to create an "artificial" fracture permeability, thus realizing the development of shale gas. The concept of hydraulic fracturing to increase the Stimulated Reservoir Volume (SRV), also known as volumetric reforming, is to "break up" the effective reservoir volume that can be percolated through fracturing, forming a network of fractures, with the fracture wall in contact with the reservoir matrix, maximizing the contact area, and allowing the oil and gas to flow from any reservoir to the next one. The contact area between the fracture wall and the matrix of the reservoir is maximized, which makes the seepage distance of oil and gas from the matrix in any direction to the fracture the shortest, which can greatly improve the overall permeability of the reservoir and realize the "three-dimensional transformation" of the reservoir in the three-dimensional direction of length, width and height. The technology started in the early 1980s, featuring "long horizontal well section + segmented multi-cluster fracturing transformation", and the technology series includes: ① large skidding water fracturing technology; ② multi-segmented multi-cluster perforation technology; ③ synchronized/cross-fracturing technology.