Some structure, with complicated geological features, in the Yumen Oilfield belongs to piedmont structure.It is difficult to control well path especially while drilling the overthrust formation.

• 玉门油田部分构造属山前构造带,地质构造十分复杂,特别是逆掩推覆体地层,钻井过程中井斜非常难以控制,采取轻压吊打则严重影响机械钻速。