Multilateral technique increases production in a mature offshore China field

摘要

Located in the South China Sea, Xijiang 24-3, Phillips' first offshore China field, went into production in 1994. The field contains a layered sand/shale reservoir with poorly consolidated sand formations with a high permeability. Production rates vary from 5,000 to 18,000 b/d with the use of electric submersible pumps. Xijiang 24-3 well A-13 was selected for sidetracking using multilateral technology to add additional reserves while maintaining the production of the existing well. At its peak this horizontal well produced a maximum of 8,500 b/d. By 1999, the production rate had declined to approximately 950 b/d. It was initially determined that a conventional horizontal sidetrack could access previously untapped reserves and potentially produce 5,000 b/d. It was also recognized that production from the original well could be preserved by using multilateral technology rather than abandoning the well, as would be the case if the it was merely sidetracked.