Abstract: Low-permeability hydrocarbon reservoir is normally characterized by high starting pressure differential, high injection pressure and serious under injection, etc. Augmented injection measures of injection wells, such as fracturing, acidizing and ultrasonic vibration, mostly have the problems of less incremental water injection rate and short response time. When injection pressure is up to the formation fracture pressure, micro-fractures will produce around injection wells, which can improve the permeability of immediate vicinity of wellbore. Injection water filtrating rapidly along fracture wall and fracture extension pressure decreasing will cause limited length and height of fracture extension and little effect on casing and barriers. By water injection close to fracture pressure at Bei-16 low-permeability reservoir, its water injection rate, formation pressure and waterflood swept area are all enlarged, with obvious response from production wells. The predicted recovery rate can be increased.

Key words: Junggar basin, low-permeability reservoir, fracture pressure, water injection, micro-fracture, barrier, casing