Dynamic Evaluation of the Development of Block A in Low Permeability Reservoirs in Changqing Oilfield

Abstract

The Block A of the low-permeability reservoir in Changqing Oilfield is located in the northern part of the Ordos Basin. The reservoir is deeply buried and the reservoir properties are poor, which makes the reservoir development difficult. Block A is mainly located in the delta front subfacies deposit, and the reservoir is dominated by underwater distributary channel microfacies. In order to improve the development of the reservoir, this paper carried out a reservoir dynamic analysis to understand in detail the current development of the reservoir. The A block is partially developed with a near-east-west nasal structure and belongs to a low permeability lithologic reservoir. The A block was developed using a diamond-shaped anti-nine point well network. The use of advanced water injection method has improved the formation pressure and the overall development effect is better. The analysis results show that with the development process, the accumulated water storage rate remains stable. This shows that the oilfield has a shorter production time and better water injection efficiency. The water content of A block is slower, the water content fluctuates, and the overall water injection effect is better. Referring to the actual development experience of similar oil reservoirs in Changqing Oilfield, the final recovery factor of the calculated A block is 22.5%. Based on the current oil price, the reasonable well pattern density of Block A is 15.6 ports/km2. The above research results evaluate the current production dynamics of the reservoir and provide a basis for further adjustment of the reservoir development plan.