Carbon and oxygen isotopes have been widely used as a means of reconstructing ancient environments. A total of 13 sandstone samples were colected from the Funing Formation (E1f1) in Gaoyou Sag, WeiMa region. A MAT-252 stable isotope ratio mass spectrometer was used to measure δ18O and δ13C in al samples. δ13C values range from -2.05‰ and -6.44‰, and the δ18O values range from -8.33‰ and -12.08‰. These values are comparable with carbonate rock marine and terrestrial isotope values, suggesting that the lakes developed into the open inland freshwater lakes in Funing Formation sedimentary period. Diagenetic tempterature is low, and the ancient productivity of the lake with piecewise sex. The ancient productivity of the lake changed from low to high with decreasing depth.%沉积岩中碳氧同位素值的测定在古环境恢复方面具有重要意义.本文采用苏北盆地高邮凹陷韦马地区阜宁组一段(E1f1)的13个砂岩样品,利用MAT-252型稳定同位素比质谱仪,精确测定砂岩样品中沉积的碳酸盐岩胶结物的碳氧同位素比值.样品的碳、氧同位素值均为负值,δ13C值在-2.05‰~-6.44‰之间、δ18O值在-8.33‰~-12.08‰之间,通过计算及与海相和陆相碳酸盐岩同位素值对比得出,高邮凹陷阜宁组一段沉积时期发育淡水陆相开放性湖泊,成岩温度较低,湖泊古生产力具有分段性,由深变浅,湖泊的古生产力具有由低变高的趋势.
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