Drilling technology for multi-lateral horizontal wells for thin reservoir in offshore oilfield

In order to improve the productivity of mid-late stage offshore oilfields, multilateral horizontal wells are used for thin reservoirs with scattered reserves and insufficient natural energy to improve the production of invidual wells and recovery rate and to reduce the comprehensive development costs. Based on the characteristics of oil reservoirs in A Oilfield in some sea area, we analyzed some issues like limited drilling equipment capability, the many restrictions in engineering design, high requirement on target hitting, multiple challenges of trajectory control, high-risk drilling operations, great difficulties in eservoir protection, etc. The research and application of evaluation and modification of the drilling equipment, optimized design of casing program and well trajectory, fine control of well trajectory and optimization of drilling fluid technology, etc. ensured the successful drilling of horizontal wells，multilateral wells, slim holes and thin reservoirs, which has improved the comprehensive benefits of oil field exploration and development and provides a reference for drilling multilateral horizontal wells for thin reservoirs in offshore oilfields.