Shale gas has becoming an important source of gas production in recent years with the advantage of completion technique development. Completion to generate desired fracture system in the reservoir is critical to shale gas production and the corresponding well performance. The impact of fracture system and completion parameters on the well performance decline curves of Haynesville shale gas wells is investigated by using both simulations and field data.

Applying numerical simulation models on horizontal Haynesville shale gas wells with regularly spaced transverse fractures, we investigated the impact of the fracture half length and total fracture surface area on the performance decline curve. The results show that the total fracture surface area defines the early production behavior during the linear flow period and the half length determines the declining slope of the main production time during the fracture interference period if the reservoir parameters are the same. If the reservoir parameters are different, the early time production behavior depends on kAcm, which is the square root of permeability times fracture surface area.

Using field data of hundreds of Haynesville shale gas wells, we observed the different performance decline curves when compared among different regions and compared among different completions in the same region. The difference of decline curves in different regions when using the same completion practice indicates that the reservoir properties are different and thus impact both generated fracture system and flows in the matrix. The difference of decline curves in different completions in the same region suggests that completion impacts the generated fracture system and thus the decline performance. Based on the study results, we can improve the completion practice to optimize well performance and completion cost.

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