Based on the study of the zircon SHRIMP chronology,the boundary between the Jurassic and the Cretaceous strata is located at the bottom of the sandstone in the Weimei Formation.

• 结合锆石SHR IM P年代学研究可以确定侏罗纪/白垩纪的界线位于前人认为的维美组上部砂岩之底。