Research Of Comprehensive Evaluation And Technical Development Strategies For Low-permeability Reservoirs In Shang 13-45 Block

With the research of sediment microfacies, remaining oil distribution and three-dimensional geological modeling, the comprehensive evaluation and technical development strategies for low-permeability reservoirs in the lower member of Es₂ of Shang 13-45 Block were studied. It was considered that here were two sedimentary cycles and the intrafomational heterogeneity was intensity. Based on the oiliness area, reserves and conformation of sand body, 39 sublayers were patitioned essential layers and non-essential layers. Then, using the black oil model of VIP petroleum reservoir simulation software from LandMark Company, the 3D geological model of three sands were built, and distribution law of remaining oil was studied. The consummation degree of injection-production system controlled the distribution of reamining oil, and the sediment microfacies with heterogeneity were the main factors of it. From the result of reservoir numerical simulation, the remaining geologic reserves was 615.9×104t. Thus, the 39 sublayers were patitioned three species, and the final recovery ratio was 30.9%. Finally, the technical and economic limits of exploitation was brought out. When the oil price was＄35 pre barrel, the limit original production of fresh wells was 3.2t/d, the limit production of old wells was 0.5t/d, the limit economy water cut was 96%, the limit economy adding oil per day of fracture in old wells was 1.5t with 340t of accumulation, and the limit economy adding oil per day of perforation was 1.5t with 210t of accumulation. Based on it, the emploitation adjustment project was given. The Shang13-14 and Shang13-19 Blocks were essential goal. The enrichment section of remaining oil of them was separated into 1-3th sands and 4th sands. The available thickness of single well was more than 10m, controlled reserves was more than 10×104t, and the distance of wells was more than 250m.