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天津蓟县元古界剖面长城系碳酸盐岩的δ~(13)C值基本为负值,蓟县系大体在(0±1)‰的范围内,进入青白口系井儿峪组一般在(2±2)‰的正值.从串岭沟组到大红峪组(约1700～1600 Ma)碳酸盐岩的δ~(13)C值大约由-3‰变化到0‰,但大红峪组δ~(13)C值大幅度振荡.蓟县系地层碳同位素组成发生两次较大的变化,分别在杨庄组和雾迷山第三亚组之后.相当完整和连续的碳同位素记录反映了约 1700～800 Ma全球海水的δ~(13)C值长期变化趋势.发生在约1700～1600 Ma和<约 1300 Ma海水的δ~(13)C值升高及大幅度振荡可能是两次全球性构造事件的响应.
The δ ~ (13) C values of the Great Wall carbonate rocks in the Proterozoic section of the Jixian County in Tianjin are basically negative, and that of the Jixian series is generally within the range of (0 ± 1) ‰, 2 ± 2) ‰ .Theδ ~ (13) C values of carbonate rocks from the Chuanlinggou Formation to the Dahongyu Formation (about 1700-1600 Ma) range from -3 ‰ to 0 ‰, but the Dahongyu The δ ~ (13) C values oscillate greatly, and the stratigraphic carbon isotopic composition of Jixian System has two major changes, which are respectively behind Yangzhuang Formation and Wumishan Sub-Group 3. The fairly complete and continuous carbon isotope records reflect The long-term δ ~ (13) C values of global seawater from about 1700 to 800 Ma.Changes in δ ~ (13) C and sea-level oscillations occurring in seawater of ~ 1700 ~ 1600 Ma and <~ 1300 Ma may be two times Response to global structural events.