Compatibility between Well Pattern and Fractures Orientation for Ultra-Low Permeability Reservoirs

Fractures play an important role in the ultra-low permeability reservoirs. The compatibility between well pattern and the fractures´ orientation has a significant impact on the development. Generally speaking, the artificial fractures extend along the natural fractures perpendicular to the minimum principal stress (i.e. parallel to the maximum principal stress). According to the reservoir fluid characteristics of the actual field, taking formation anisotropy into account, this paper utilizes nonlinear seepage numerical simulation to study the match between well row and the fractures position. Herein four programs indicating different angles between fractures and well array, which is 0°,12.5°,32.5°,45° respectively. The result shows that: with the angle increasing, the production rate increases and the development effect improves gradually. For the square inverted nine-spot flooding pattern, when the angle is 45°, the fractures match the well pattern best.