寒武纪大爆发后不久，泥石流迅速将数千只海洋动物掩埋在有利于石化的条件下。

Shortly after the Cambrian explosion, mud slides rapidly buried thousands of marine animals under conditions that favored fossilization.

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原生代的，元古代的前寒武纪两个时期中的后一个时期的，属于这个时期的，在这个时期的在这个时期海绵、海洋蠕虫和其它形式的海洋生命出现。

Of, belonging to, or being the later of two divisions of Precambrian time, during which sponges, sea worms, and other forms of sea life appeared.

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