Fracture Optimization in a Giant Gas Field, Wamsutter, Wyoming, USA

摘要

Optimization of fracture stimulation treatments in BP’s giant Wamsutter Field is an important aspect of efficient and viable development of this tight gas asset. This paper integrates historical fracturing data, well performance, surveillance data, and data from fracturing field trials to provide a clearer view of created fracture geometry and resulting well performance. This integrated understanding of Wamsutter fracturing is being used to design additional field trials with a calibrated, more predictive fracture model. The results of this analysis could directly apply to similar tight gas fields. The evaluation technique of integrating field results with surveillance data and field trials would be beneficial for any unconventional gas asset in defining the most effective fracturing techniques. Major conclusions of this study: 1 Fluid Volumes pumped during fracture stimulation have a strong correlation to the well performance in Wamsutter Field. 2 Shale boundaries within the Almond are not always effective in preventing frac height growth. Microseismic indicates that stages frequently grow into each other. 3 A predictive fracture model with a calibrated geomechanical profile is essential for designing and understanding stimulation results. 4 A field trial program to test fracture design concepts and calibrate fracture models is an important aspect of fracture optimization. Fracture geometry is difficult to model and design accurately. This case study, based on a large data set, provides some “ground truth” to measure the accuracy of design versus actual results.