摘要：The Shunbei oil and gas field is one of the major oil and gas discoveries in the deep west of China,which has a broad prospect of exploration and development.Due to the deep burial of oil and gas reservoirs in this area and the complex regional geological conditions,there are fracture zones,fault zones,geological permeability and fracture loss,which lead to the frequent occurrence of complex underground accidents in this area,especially the risk of well leakage engineering is the most obvious.In order to effectively avoid the risk of well leakage engineering,the author divides the Shunbei block into three geological blocks,namely,the northern part of The No.1 fault zone,the northern part of the No.5 fault zone and the junction of the No.1 fault zone and the No.5 fault zone.Combined with the narrow density window in The Shunbei area,the optimization design of the well casing structure in these three blocks is innovatively carried out,two feasible schemes are put forward to adjust the well casing structure and improve the formation bearing capacity to avoid the complicated underground conditions.The feasibility analysis of risk assessment for the proposed scheme is carried out,and the calculation result shows that the whole well section is risk-free.The feasibility of the scheme is proved,which has certain guiding significance to the field practice.
关键词：Geological block division;Regionalized safe drilling fluid density window;Design and optimize well structure;High formation bearing capacity;Shunbei Area
