Linking fracture orientation with inclined well trajectory to evaluate production performance in CBM reservoir
摘要
In the Indian Coalbed Methane (CBM) reservoir, both vertical and inclined wells are drilled. Often complications are observed in well completion and production performance of inclined wells. This study aims to understand the production performance of inclined wells by analyzing the well trajectory and coal seam’s fracture orientation. Over the period, it was observed that the production performance of inclined wells varies and it surprises more for the padded wells from the same location. Therefore, we have investigated the fracture geometry network of five prospective coal seams and linked well trajectories to evaluate the production history of 33 inclined wells. A seam-wise fracture orientation map was generated using resistivity image and sonic logs infused with inclined well trajectory and bubble plot representing the gas–water production ratio. The findings reveal a consistent directional alignment between fractures and fast shear wave orientation. It is observed that the production efficiency of inclined wells passing across fractures is higher compared to along the fractures considering the other parameters such as seam encountered, thickness, activated seams for production, artificial pump running hours, and fault blocks are comparable. The result shows that the gas–water production ratio of the padded wells increases by 63-1138% as the angle between the well’s trajectory profile and fractures increased by 30° to 60°. This study will help to design future inclined wells for production efficiency.