Drilling Technologies for Horizontal Shale Oil Well Fan Yeping 1 in the Shengli Oilfield

The Dongying Sag possesses rich shale oil but due to its complex geological conditions of the oil and gas reservoir, downhole problems such as collapse, spalling, and oil and gas invasion are frequently encountered during drilling. A horizontal shale oil well, Well Fan Yeping 1, was deployed to explore the oil-bearing situation of shale formation at the upper Chun submember of the fourth member of the Shahejie Formation in the northern part of the Boxing Subsag of the Dongying Sag. In accordance to the exploration objectives, engineering design was made on the well. Then, with the lithology of the formation encountered during the drilling of Well Fan Yeping 1, the difficulties in drilling technologies were analyzed. On this basis, optimization technology for wellbore trajectory, the technology for synthetic base drilling fluid, and safe drilling technology were developed. With these technologies, the construction of Well Fan Yeping 1 was completed. Good results were achieved, with no downhole problems and a small hole diameter enlargement rate. The successful application of the drilling technologies to Well Fan Yeping 1 have accumulated experience for the drilling of shale oil in the Shengli Oilfield.