Physical Models for Inter-Well Interference in Shale Reservoirs: Relative Impacts of Fracture Hits and Matrix Permeability

摘要

The objective of this study is to develop physical models to quantitatively simulate the pressure response of well interference through fracture hits with complex geometries. Our study offers a model for an improved understanding of the influence of key reservoir and fracture properties on intensity of well interference, which may help field operators to further optimize the spacing of wells in a multi-well pad. We combine numerical, semi-analytical, and analytical model tools to identify, analyze, and visualize the inter-well interference process. Our analysis can account for complex non-planar fracture geometries using a semi-analytical model. The stimulated rock volume is visualized by an analytical streamline model. Three scenarios for well interference are investigated including interference through a single slanted fracture hit, multiple slanted fracture hits, and multiple complex fracture hits. For the first scenario, we examine the effects of connecting fracture conductivity, primary fracture conductivity, and matrix permeability on the pressure response of a shut-in well. For the second scenario, we vary the number of connecting fractures to investigate the impact on the pressure response of a shut-in well. For the last scenario, we use a complex fracture propagation model to generate non-planar fracture geometries with and without natural fractures. The semi-analytical model is used to evaluate the effect of both hydraulic and natural fractures on the pressure response of a shut-in well. The simulation results show that the pressure drop of the shut-in well increases with the increasing conductivity of connecting fractures and primary fractures and number of connecting fractures, while decreases with the increasing of matrix permeability. Furthermore, the pressure drop of the shut-in well through complex fracture hits without natural fractures is larger than that with natural fractures.