Optimization Technology of Well Trajectory of Shale Oil Horizontal Well Group in Cangdong Sag

Abstract

AbstractThe optimization of well trajectory of horizontal well group of shale oil in Cangdong sag is confronted with difficulties such as development with cluster wells, deep buried, long horizontal section and large offset distance. Meanwhile, special lithology and fault development in the region restrict the optimization of well trajectory. Through the analysis of well trajectory constraints factors, it is researched including integrated geo-engineering well pattern deployment, pre deflection in upper interval to avoid collisions with adjacent wells, the optimization of three-dimensional horizontal well profile, fine optimization of well trajectory parameters and so on. Combined with the analysis of each simulated drilling condition operating, it is researched including the optimize of the friction, torque, which can reduce the difficulty of casing running, loss circulation and other complex conditions. The optimization method of wellbore well trajectory of horizontal well group of shale oil in Cangdong sag is formed, which meets the demand of geological to the greatest extent, improving the rate of penetration, reducing the drilling cost. This method has been applied in 42 wells in shale oil development Cangdong sag, achieving 2–8 wells on a single platform Wells, with an average well depth of 4740 m, an average horizontal section length of 912 m, a maximum offset distance of 867.38 m and a minimum pre-target displacement of 36.06 m. The research results show that this technology can guarantee the low cost and efficient development of horizontal wells in Cangdong sag, and it has a reference value for the development of similar areas.KeywordsHorizontal well groupWell trajectoryCluster wellIntegration of geology and engineeringShale oilCangdong sag