总的特征 (一)定义始寒武系指加丹加地壳旋回以后的各类地质沉积,即6.8—6.5亿年至6.7亿年的沉积。所以始寒武的延续时间有100—80百万年。这样,它比前寒武系任一地层单位延续时间都短,并且与那些用构造旋回所划分的“代”或“亚代”也有很大不同。始寒武与新原生界以大的地壳变动来划分,而与寒武系之间未发现有任何构造事件。 General characteristics (a) Definition The beginning of Cambrian refers to the Katanga crustal cycle after the various types of geological deposition, that is, 6.8-6.5 billion years to 670 million years of sediment. Therefore, the beginning of the Cambrian duration of 100-80 million years. As such, it lags behind any of the Precambrian strata, and is also very different from those “generations” or “generations” that were subdivided into tectonic cycles. The Cambrian and Neogene were divided by large crustal changes, but no structural events were found between them with the Cambrian.