Abstract: Based on the status and distribution characteristics of the remaining oil and reserves of Sangonghe reservoir in Cainan oilfield, the block suitable for drilling horizontal well is selected, the feasibility of the horizontal well is demonstrated and the well location design is opti mized. Through real-time control by means of composite log, cutting log and 3D geologic model and other technical methods, the operation for bypassing the fault is realized and higher oil layer drill-encountering rate is achieved successfully. And the productivity by horizontal drilling process after putting into production meets the demand of the project design, obtaining good economic efficiency. The successful implementa tion of this scheme opens up wider spaces for developing the remaining oil in bottom water fault-block reservoirs in Cainan oilfield.

Key words: Cainan oilfield, reservoir description, fault bypass, horizontal well