Abstract: Determination of the optimum shale gas well spacing is to a large extent dependent on the assessment of fracturing performance. To tackle this problem, we explored the parameters associated with the reconstruction of horizontal wells used for multi-stage fracturing. Based on this exploration, we further optimized the shale gas well spacing. By establishing a mathematical model of seepage flow, we determined the flow regime existing in the formation of a shale gas well and furthermore developed a method to rationalize the fracturing parameters based on linear flow identification and the feature line diagnostic technique. The uncertainty associated with the parameter rationalization is also analyzed and discussed in this study. Finally, the optimum well spacing under uniform fracturing condition was determined by defining the total gas production over a 100-m stratum. The results demonstrate that the half length of the crack can be accurately determined without affecting the prediction of the production capacity of the gas well once the formation is under boundary control flow. The key factor in determining the well spacing is the half length of the crack. The relationship between these two parameters is affected by the relative physical properties and flow conductivity of the fracture inside and outside the SRV. These findings can provide guidance for performing well spacing optimization and policy-making associated with the extraction techniques.

Key words: shale gas, fracturing horizontal well, SRV, rationalization of reconstruction parameters, well spacing optimization