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前寒武纪—寒武纪 ( PC— C)边界处两个明显不同演化阶段的地层主要根据以下几点事区别 :1可视后生动物组合的变化 ;2化石埋藏条件的变化 ;3痕迹化石组合的变化 ;4寒武纪最早期海洋沉积物中生物扰动强度的增加。生物的这种不连续性归因于生物大量灭绝以及软体生物化石埋藏窗的
The two distinctly different stages of evolution in the Precambrian-Cambrian boundary are stratigraphic differences based on: 1 changes in visual assemblages; 2 changes in fossil burial conditions; and 3 traces of fossils Changes in assemblages; 4 Increased bioturbation intensity in the earliest marine sediments of the Cambrian. This discontinuity in biology is attributed to the mass extinction of creatures and the burial of soft-tissue fossils