Application Research on Lost Circulation Prevention and Plugging in Fuling Shale Gas Field

Abstract:

Lost circulation control is the biggest problem in the development process of Fuling shale gas field. According to statistics, different degrees of lost circulation occurred in 67.2% wells during drilling, which has bad affect on the engineering quality, the construction progress and the economic benefit; especially the lost circulation of oil-based drilling fluid in the three opening and long horizontal section, which caused serious economic losses. In order to reduce the risk of drilling engineering, improve drilling efficiency and reduce drilling cost, starting from the actual situation on site, the statistical analysis was made on drilling leakage, it was thought that in middle-shallow layer were mainly karst cave leakage and fracture-cavity type leakage; in Longmaxi formation and Wufeng formation was mainly fracture type leakage. The paper introduces the lost circulation prevention and plugging technologies adopted in Fuling shale gas field according to the characteristics of each opening and the field application. Along with the development region extension, the geological conditions become changing and the leakage is more complicated, the next development direction of lost circulation prevention and plugging technologies are put forward with some suggestions.