The sediments of the Early Cretaceous were dominated by clastics.Black shales were mainly developed in the member 4 and member 5 of Kuco Formation and Dongshan Formation of the Lower Cretaceous.

• 早白王垩沉积以碎屑物质为主，黑色页岩主要集中于下白垩统古错四组、古错五组和东山组。