The precipitation of Doushantuo cap carbonates was deposited in warm, brackish water, and between the intertidal-subtidal inner ramp and shallow basin.

Having mastered the relatively shallow waters, the oil companies are now exploring in the Orphan Basin, where a depth of 2,500 metres presents new challenges.

A refraction seismic tomographic method is proposed for the first time to determine the distribution of seismic velocity in shallow levels in Talimu Basin.