Intelligent, comprehensive analytical model and optimization method for well type/trajectory and pad deployment during cluster drilling

Cluster well is a new concept of well pad development which still requires further scrutiny. The concept has the potential to significantly improve the economic efficiency of well pad drilling, one of the most capital-intensive processes in the upstream sector of the petroleum industry. During cluster drilling, pad deployment planning is considered independent of well type/well trajectory design. Therefore, it is difficult to achieve the optimal configuration of cluster drilling without considering the impact of pad deployment on well type optimization and trajectory optimization for different well types and vice versa. This paper proposes a numerical model for intelligent and comprehensive optimization of well type/trajectory and pad deployment during cluster drilling, which can automatically optimize the location, scale, and the number of pads, well type, and well trajectory. The decision-making goal was to minimize costs by optimizing pad location using the K-means dynamic clustering algorithm and simultaneously dividing well-targeted cells into different pads. Additionally, well type was optimized by calculating the ratio of horizontal distance to vertical depth between the pad and target affiliated with the pad, and well trajectory was optimized by the parameters, such as the maximum deviation angle, etc., of each well. Then, the total cost of the whole block was estimated from the sum of the unit well depth costs of different well types and the construction cost of each pad, and finally, the number of pads was optimized. Finally, the model was demonstrated through case studies examining the cost of cluster drilling in tight reservoirs in the Jiyang sag of the Bohai Bay Basin, China.

Automated summary

Cluster well is a new concept that can significantly improve the economic efficiency of well pad drilling in the petroleum industry. This paper proposes a numerical model to optimize well type/trajectory and pad deployment during cluster drilling, considering the impact of pad deployment on well type optimization and trajectory optimization.