关键词: 页岩气, 立体开发, 缝控压裂技术, 压裂液, 威远区块, 四川盆地

Abstract: Although the physical conditions of shale reservoirs in Sichuan Basin are superior, the height of fractures formed by SRV fracturing is limited, making it difficult to develop the high-quality shale reservoirs with a thickness of tens of meters vertically. To solve this problem, an infilled well test was conducted on the X platform of Weiyuan Block, and new wells were under reservoir sitmulation by fracture-controlled fracturing technology, so as to explore the feasibility of tridimensional development of this block. The results show that: with the increase of induced stress between clusters by close-spaced fracturing technology, the propagation path of hydraulic fractures gets more complex. Considering the annual production and construction cost, the optimal cluster spacing is about 10 m. Temporary plugging agent deflection technology is beneficial to enhance oil recovery. When the temporary plugging agent is injected after 50% of the total fluid volume is injected, the propagation of multi-cluster fractures is the most uniform. The multi-functional integrated fracturing fluid can achieve the stepless viscosity variation and the alternating injection of variable-viscosity fluid, making the main fracture and complex fracture progapate at the same time. The fracture-controlled fracturing technology has been applied to the Weiyuan shale gas reservoir. The cumulative gas productions of the three new wells were 1.85, 1.36 and 1.55 times of the cumulative gas production of the three neighboring old wells in 90 days, 1 year and 2 years a after the new wells are put into production, showing good fracturing effect. This technology can be used as reference for the trimensional development of shale gas well clusters.

Key words: shale gas, tridimensional development, fracture-controlled fracturing technology, fracturing fluid, Weiyuan Block, Sichuan Basin