Author(s)

Shaopeng Wang, Pengfei Mu, Jie Tan, Rong Fu, Mo Zhang

Tianjin Branch of CNOOC Ltd., Tianjin, China.

The BZ 34-1 oilfield is a typical gas cap edge water reservoir in the Bohai oilfield. The main characteristics of the oilfield were multi-phase sand body stacking and the sand body was composed of three parts: gas cap, oil reservoir, and edge water. The actual production site results show that the permeability difference of multi-layer sand bodies has a serious impact on the development effect. This article establishes a typical reservoir model numerical model based on the total recovery degree of the reservoir and the recovery degree of each layer, and analyzes the impact of permeability gradient. As the permeability gradient increases, the total recovery degree of all four well patterns decreases, and the total recovery degree gradually decreases. The recovery degree of low permeability layers gradually decreases, and the recovery degree of high permeability layers gradually increases. As the permeability gradient increases, the degree of recovery gradually decreases under different water contents. As the permeability gradient increases, the reduction rate of remaining oil saturation in low permeability layers is slower, while the reduction rate of remaining oil saturation in high permeability layers was faster. By analyzing the impact of permeability gradient on the development effect of oil fields, we could further deepen our understanding of gas cap edge water reservoirs and guide the development of this type of oil field.

Bohai Sea, Gas Cap and Bottom Water Reservoir, Permeability Gradient, Well Pattern, Recovery Degree

Wang, S. , Mu, P. , Tan, J. , Fu, R. and Zhang, M. (2023) Adaptability of Development Methods for Offshore Gas Cap Edge Water Reservoirs under Different Permeability Levels. Open Journal of Applied Sciences, 13, 1029-1038. doi: 10.4236/ojapps.2023.137082.