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新疆柯坪地区新元古代晚期海相碳酸盐岩地层的碳同位素测定结果表明:奇格布拉克组和苏盖特布拉克组上亚组碳同位素组成总体以正δ13C值为主,并且在奇格布拉克组下部出现了一个明显的δ13C正漂移;在寒武系与奇格布拉克组之间、苏盖特布拉克组上亚组顶部及底部等3个层位出现了3个δ13C负漂移.这些特征与华南三峡地区新元古代晚期碳同位素变化特征相似,表明苏盖特布拉克组上亚组和奇格布拉克组分别相当于三峡地区的陡山沱组中、上部和灯影组.其中苏盖特布拉克组上亚组顶部的δ13C负漂移对应于三峡地区陡山沱组顶部的负漂移,而苏盖特布拉克组上亚组底部的δ13C负漂移可同陡山沱组中部以及库鲁克塔格地区汉格尔乔克组冰碛岩顶部的δ13C负漂移对比.
The results of carbon isotopic measurements of marine Neoproterozoic marine carbonate rocks in the Keping area of Xinjiang suggest that the δ13C values of the upper subgroups in the Qigbulak and Sukkot Blake groups are mainly positive δ13C, There is a clear δ13C positive drift in the lower part of the Chikbuluk Formation. Between the Cambrian and Qigburak groups, there are three δ13C at the top and bottom of the upper subgroup in the Sukkot Blake Formation These characteristics are similar to those of late Neoproterozoic carbon isotope in the Three Gorges area in South China, indicating that the Upper Subgroup and the Chigibulak Formation in the Upper Southampton Region correspond to the upper and middle portions of the Doushantuo Formation in the Three Gorges area respectively The δ13C negative drift at the top of the Upper Subgroup in the Sukkot Blake Formation corresponds to the negative drift at the top of the Doushantuo Formation in the Three Gorges area and the δ13C negative drift at the bottom of the Upper Suet Group in the Sukkot Blake Formation can be compared with that of the Doushan Tu Δ13C negative drift of the top of the moraine rocks in the Hangeljokk Formation in the central part of the group and in the Kuruktag area.