TY  - EJOU
AU  - Deng, Qi 
AU  - Ruan, Qi 
AU  - Zeng, Bo 
AU  - Liu, Qiang 
AU  - Song, Yi 
AU  - Cheng, Shen 
AU  - Tang, Huiying 

TI  - 4D Evolution of <i>In-Situ</i> Stress and Fracturing Timing Optimization in Shale Gas Wells
T2  - Fluid Dynamics \& Materials Processing

PY  - 2025
VL  - 21
IS  - 5
SN  - 1555-2578

AB  - Over more than a decade of development, medium to deep shale gas reservoirs have faced rapid production declines, making sustained output challenging. To harness remaining reserves effectively, advanced fracturing techniques such as infill drilling are essential. This study develops a complex fracture network model for dual horizontal wells and a four-dimensional <i>in-situ</i> stress evolution model, grounded in elastic porous media theory. These models simulate and analyze the evolution of formation pore pressure and <i>in-situ</i> stress during production. The investigation focuses on the influence of infill well fracturing timing on fracture propagation patterns, individual well productivity, and the overall productivity of well clusters. The findings reveal that, at infill well locations, the maximum horizontal principal stress undergoes the most significant reduction, while changes in the minimum horizontal principal stress and vertical stress remain minimal. The horizontal stress surrounding the infill well may reorient, potentially transitioning the stress regime from strike-slip to normal faulting. Delays in infill well fracturing increase lateral fracture deflection and diminish fracture propagation between wells. Considering the stable production phase and cumulative gas output of the well group, the study identifies an optimal timing for infill fracturing. Notably, larger well spacing shifts the optimal timing to a later stage.
KW  - Shale gas; infill well; numerical simulation; <i>in-situ</i> stress; fracturing timing

DO  - 10.32604/fdmp.2025.060311