Progress and prospects of horizontal well fracturing technology for shale oil and gas reservoirs

By systematically summarizing horizontal well fracturing technology abroad for shale oil and gas reservoirs since the "13th Five-Year Plan", this article elaborates new horizontal well fracturing features in 3D development of stacked shale reservoirs, small well spacing and dense well pattern, horizontal well re-fracturing, fracturing parameters optimization and cost control. In light of requirements on horizontal well fracturing technology in China, we have summarized the technological progress in simulation of multi-fracture propagation, horizontal well frac-design, electric-drive fracturing equipment, soluble tools and low-cost downhole materials and factory-like operation. On this basis, combined with the demand analysis of horizontal well fracturing technology in the "14th Five-Year Plan" for unconventional shale oil and gas, we suggest strengthening the research and development in the following 7 aspects: (1) geology-engineering integration; (2) basic theory and design optimization of fracturing for shale oil and gas reservoirs; (3) development of high-power electric-drive fracturing equipment; (4) fracturing tool and supporting equipment for long horizontal section; (5) horizontal well flexible-sidetracking drilling technology for tapping remaining oil; (6) post-frac workover technology for long horizontal well; (7) intelligent fracturing technology.