孙云铸教授是著名的地质学家和古生物学家。他在前寒武纪地层研究的贡献是：①发现和命名蓟县运动，正确解决了华北震旦系与寒武系的分界问题；②坚持震旦系与寒武系的不同，确定了震旦系及青白口群的元古代归属；③较早发现南北震旦系的差异，最早指出南北不同标准剖面；④坚持震旦系的重要地位，最早提出震旦系为震旦界。 Professor Sun Yunzhu is a famous geologist and paleontologist. His contribution to Precambrian stratigraphic research is: ①The discovery and naming of the Jixian movement correctly solved the boundary problem between Sinian and Cambrian in North China; ② Adhering to the differences between the Sinian and Cambrian strata, Department and the Qingbaikou group of the Proterozoic attribution; ③ earlier discovered the difference between North and South Sinian, North and South first pointed out that the different standard profiles; ④ insist on the important position of the Sinian, earliest proposed Sinian as the Sinian community.