Interwell stress interference due to hydraulic fracturing infill well of Mahu conglomerate reservoir in Xinjiang, northwest China

ABSTRACT: Stimulation of unconventional tight oil formations via horizontal wells has seen increasing cases of fracturing infill wells in recent years. However, the increase of infill wells has resulted in interwell interference, which can cause a severe decline in production. It is necessary to examine the influences of the hydraulic fracturing of infill wells to determine a reasonable distance between the interwell. This paper established a customized extended finite element method (XFEM) to evaluate the impact of well spacing and fracturing sequence on hydraulic fracture propagation in infill wells. Studies have shown that fracturing will cause the Sh direction on both sides of the fracture surface to be deflected by 90°, while having little influence on the area of fracture tip. Reducing well spacing will increase interwell interference causing asymmetric fracture propagation and fracture-hits. Sequential fracturing can get a larger SRV, and when the well spacing is 100m, the fractures of the two wells communicate. The findings of this study can help the field engineers make the efficient design on wellbore trajectory for infill well fracturing.