Study On Production Optimization Of Complex Fault Block Reservoir In Weizhou 6-12 Oilfield

Complex fault block reservoir is widely distributed in our country, its reserves and production accounts for a considerable proportion in the development. In this paper, the example is WeiZhou6-12oilfield that is located in the northern South China Sea Northern Bay Basin. WeiZhou6-12oilfield is a typical complex fault block reservoir, owning obviously complex fault block oil reservoir geological characteristics.Based on the literature research home and aboard, study the Weizhou6-12oilfield in the development process problems that are oil production declining quickly, the production horizon between mutual interference, excessive production rate, the formation pressure drops quickly and the low part well water outlet. Combined with the geologic and exploitation features of WeiZhou6-12oilfield, this paper studied the following several subjects and got the corresponding research results:(1) The structure characteristics, sedimentary characteristics, reservoir properties and fluid characteristics of WeiZhou6-12complex fault block reservoir are analyzed and summarized. Study on the type of reservoir and the reservoir natural energy is evaluated.(2) The status of reservoir development is analyzed. Testing the productivity of A1/A2/A4/A6/A3S1/A7wells respectively and finding out the reasons of target area did not reach the allocation, then find out the law of production decline. In view of the high air/oil ratio in some production levels of the production process, analysis of the existence of gas cap through single well dynamic analysis method.(3) Because the reservoir is mostly edge water reservoir, well water should be considered in the process of mining, which control the oil production rate as well as prevent water from promoting faster. The distribution of fluid in different regions is studied and establish the fluid distribution model.(4) Multilayered reservoirs exist, there may be interference between layers commingling process, making the degree of development of the oil group inequality.Simulation studying on oil well production horizon combination and single well working system and the development of supplementary energy effect by the numerical simulation. The best recommended scheme should be obtained from comparison of these production optimization results and forecast development index. Large production rate of reservoir and a fast rate of descent lead to water out in the low part wells.