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对西藏南部定日地区特提斯喜马拉雅晚白垩世坎潘期海相沉积进行高分辨率碳氧同位素分析,获得较为丰富的实验数据。分析表明,δ13C值在坎潘期呈现二高二低变化:坎潘早期较低,平均值约1.2‰～1.3‰;坎潘中期持续升高,平均值1.9‰～2.0‰,并形成正偏高原,到剖面196m位置达到最大值约2.3‰;坎潘晚期变低,平均值在1.2‰～1.4‰范围;坎潘末期再一次升高,均值达2.0‰左右。其中,坎潘中期的正偏高原全球对比研究暗示可能与南半球特别是南极大陆高温和高降雨量有关。根据δ13C值偏移幅度和时间跨度,在坎潘早期、中期和晚期识别出三次负偏事件Ⅰ、Ⅱ、Ⅲ,分别对应于有孔虫G.elevata带下部(剖面162～166m)、G.ventricosa带下部(188～192m)和G.ventricosa带-G.stuartiformis带界线(226～230m),时间跨度平均小于0.74Ma,它们显示了与欧洲同期δ13C值偏移事件的可比性和与Haq等全球I型层序低海平面的相关性。
High-resolution carbon and oxygen isotope analyzes of the Cretaceous Campanian marine sediments in the Tethys Himalayas in the Dingri area, southern Tibet, have yielded comparatively rich experimental data. The results showed that the δ13C value showed a high and a low diurnal variation in the Campanian stage: the early stage of Campan was lower with an average of about 1.2 ‰ to 1.3 ‰, and the mid-stage of Campan continued to rise with an average of 1.9 ‰ to 2.0 ‰ and formed a positive plateau , Reaching a maximum value of about 2.3 ‰ at the 196m position of the profile. The late Campanian became lower with an average value ranging from 1.2 ‰ to 1.4 ‰. The end of the Campanian once again increased with an average of about 2.0 ‰. Among them, the mid-Campanca positive meta-plateau global comparative study suggests that it may be related to the high temperature and high rainfall in the southern hemisphere, especially the Antarctic continent. According to the δ13C shift and time span, three negative partial events Ⅰ, Ⅱ and Ⅲ were identified in the early, middle and late stages of Campan, corresponding to the lower part of the G.elevata zone of foraminifera (162-166m in section) The demarcation line of ventricosa band (188-192m) and G.venucosa-G.stuartiformis (226-230m) with an average time span of less than 0.74Ma shows comparability with the δ13C value shift event in Europe and with Haq et al. Relevance of global I-type low-level sea level.