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中文摘要：
碳酸盐岩中碳同位素组成的演化对于古环境研究有重要意义。笔者研究了浙江煤山剖面的新元古代地层陡山沱组和灯影组中δ^13C，δ^18O,^87Sr/^86Sr以及微量元素含量的演化。
英文摘要：
The evolution of δ^13C, δ^18O, ^87Sr/^86Sr and trace elements contents in Neoproterozoic Doushantuo Formation and Dengying Formation of Zhejiang Province was studied. It is held that ^87Sr/^86Sr ratios have been modified by diagenesis. Most of the samples recorded primary C isotope compositions. The extremely low δ^13C values of the cap carbonate might have resulted from several factors. As the organic productivity, the CO2 concentration in atmosphere and the ocean circulation recovered after the Snowball Earth event, δ^13C steadily shifted to normal positive values in the main Doushantuo periods. After the withdraw of a large amount of CO2 from the atmosphere as a result of weathering and organic carbon burial, the climate became cool, which induced thermohaline circulation and led to the upwelling of deep ocean water rich in ^12C. These factors caused the negative excursion of δ^13 C along the Doushantuo-Dengying boundary and increased the CO2 concentration in the atmosphere to a normal level. During most time of the Dengying period, the oceanic and climatic conditions were kept in a state favoring the ecosystem, yielding positive δ^ 13C values in most part of the Dengying Formation.
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