Fine Correlation and Well Pattern Optimization of Extra-high Water Cut Reservoirs: Case Study of-With Fuyu Oilfield as an Example

Invalid or inefficient circulation of water injection is aggravated in the development stage of extra-high water cut reservoirs. Under current well pattern conditions, the production degree is uneven in horizontal and vertical directions, and the remaining oil distribution is highly dispersed and locally enriched. To reveal the relationship between different well pattern conditions and the remaining oil development effect, based on stratigraphic boundary division and vertical and horizontal sublayer division parameters of ultra-high water cut reservoirs, this study proposed well pattern optimization methods such as co-injection and co-production, comprehensive inter-injection and symmetrical alternation in drainage of ultra-high water-cut reservoirs. According to fine reservoir correlation principle and reservoir numerical simulation method, the original reservoir potential and production status were determined and the remaining oil development effect was evaluated. The rationality of well pattern optimization was verified by using Fuyu oilfield as an example. The results demonstrate that combining new and old wells can increase the stage production by approximately 2% in different development modes. Different cycle settings and separate injection and production combinations can decrease interlayer interference and improve the development effect. The study can provide a good reference for fine reservoir correlation and well pattern adjustment of the same type of reservoirs in the ultra-high water cut development stage. © 2022. School of Science, IHU. All rights reserved.