Abstract: In response to the problems of low recoverable reserves and poor commercial benefits of single well with vertical well fracturing in low-permeability conglomerate reservoir in Well Block Ma18, Aihu Oilfield, the parameter design and productivity prediction of multi-stage fractured horizontal wells were investigated by numerical reservoir simulation, reservoir engineering method, economic limit method and mine field test method. The results indicated that the "sweet spot" depth in Well Block Ma18 was 3 876 to 3 881 m, the horizontal well strike should be in north-south direction, the recommended length of horizontal interval in horizontal well was 1 200 to 1 400 m, the well spacing was 500 m, the fracture half-length was 150 m, and the fracture spacing was 50 m. Six multi-stage fractured horizontal wells were designed with optimized parameters, achieving an average daily oil production of 29.0 t/d in the first year, which was consistent with the predicted production of 25.0 to 33.0 t/d. This study developed an oil saturation prediction method for conglomerate reservoir, and developed a method of parameter design and productivity prediction for multi-stage fractured horizontal wells in conglomerate reservoir, providing a reference for similar reservoirs.

Key words: low-permeability conglomerate reservoir, multi-stage fractured horizontal well, productivity prediction, Aihu Oilfield, Well Block Ma18