这些岩层富含化石，其中有快速进化的海洋生物，比如鹦鹉螺化石，岩层与火山灰岩交错排列。

These rocks consist of fossil-rich layers containing rapidly evolving Marine organisms such as ammonites, interleaved with layers of volcanic ash.

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岩石中粒序层理、交错层理不太发育，指示该组岩层层序是倒转的，即北老南新。

It is not developing that the middle grain sequence lamination and the crossing lamination that indicate this formation's sequence is reversal and the northern rocks is older than the southern rocks.

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