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对西南地区的１９个晚二叠世碳酸盐岩型煤系剖面进行了碳酸岩稳定同位素的测定，探讨了其“年代效应”的校正及古盐度与古温度计算问题。结果表明：在兴文、贵阳、金沙、南桐、重庆一线以西的地区，Ｚ值＜１２０，δ１３Ｃ值明显低于此线以东的地区，但与Ｓｃｈｏｐｆ给出的淡水石灰岩的δ１３Ｃ范围相比偏高，说明为海陆过渡相沉积；而此线以东的地区Ｚ值＞１２０，δ１８Ｏ、δ１３Ｃ均说明为海相沉积，与以前的沉积环境研究结论一致。用校正后的δ１８Ｏ计算出碳酸盐岩形成时的介质古温度为１４．８－５０．９℃，且大多在２３－３１℃，说明当时该区为温暖－炎热的气候，与古地磁资料显示的当时该区处于赤道附近的热带地区的结论基本一致。
Carbonate stable isotopes were measured for 19 Late Permian carbonate coal measures in the southwestern part of China. Corrections of “dating” and paleosalinity and palaeontology were discussed. The results show that in the areas of Xingwen, Guiyang, Jinsha, Nantong and Chongqing, the Z value is less than 120 and the δ13C value is obviously lower than those to the east of this line, but compared with the δ13C range of the freshwater limestone given by Schopf High, indicating that the transitional facies sediments; and east of this line Z value> 120, δ18O, δ13C are described as marine sediments, consistent with the previous conclusions of sedimentary environment. Based on the corrected δ18O, the palaeoclimate of carbonate rocks was calculated to be 14.8-50.9 ℃, mostly at 23-31 ℃, indicating that the area was warm-hot at that time, The conclusion of the area at that time in the tropics near the equator was basically the same.