A Coupled Geomechanics-Reservoir Simulation Workflow to Estimate the Optimal Well-Spacing in the Wolfcamp Formation in Lea County

This paper aims to present a workflow to estimate optimal well-spacing in the Wolfcamp A formation in Lea County, New Mexico. The failure to predict optimal well-spacing could lead to well communication, which is the root cause of low hydrocarbon recovery. In such scenarios, a coupled geomechanics-reservoir model can provide a handy approach for well-spacing optimization. First, the geomechanical properties of the reservoir obtained from a mechanical earth model (MEM) were coupled with a 3D geological model to estimate the fracture propagation of the existing (parent) well. The fracture geometry of the parent well was validated by history matching the production data. Then, the matched model was used to simulate fracture propagation of the infill (child) well. Simulation results show that fracture geometry, fracture permeability, and relative permeability in the fractured zone are the most sensitive factors in the history matching. The estimated fracture geometry of the parent well ranges from 150 to 900 ft half-length and 100 to 400 ft height for each fracture stage. Spacing analysis between two wells based on the coupled geomechanics-reservoir model was conducted from 600 to 1300 ft with 50-ft increment. It provides an optimal spacing to avoid fracture hit and maximize the ultimate recovery. The novelty of the proposed approach is the ability to simulate fracture growth of the child well in 3D using the coupled geomechanics model. Based on the fracture propagation estimation of both wells, optimizing the total oil recovery of both wells is feasible.