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对取自中国黔桂地区广西桂林水南洞、贵州都匀七星洞及荔波董歌洞的7根大型石笋,进行了系统的120件TIMS-U系测年及1295件稳定同位素分析,揭示的气候变化记录时限范围为25万年前至今,氧同位素样品平均分辨率为150～300a。研究表明,相当于海洋记录冰期旋回 、 、 终止点的石笋氧同位素跃变事件,其年龄值分别为11.3kaB.P.,129.3中kaB.P.及242.5kaB.P.。相当于海洋同位素阶段MIS1～MIS7各阶段界线的年代及其延续时间,通过石笋记录也得到了准确的界定,此外还揭示出了25万年来东亚季风气候的波动过程和变化规律。黔桂地区25万年来的气候在千年尺度上与深海氧同位素记录的可比性,及与N65°夏季太阳幅射能量变化的一致性,显示了亚洲古季风的气候变化规律,同样受轨道参数变化周期以及全球冰量变化所驱动。
A total of 120 systematic TIMS-U dating and 1295 stable isotope analyzes of seven large stalagmites collected from Guinan, Guilin, China, Qiduang Cave, Duyun, Guizhou Province and Dongge Cave, Libo, Guizhou Province, China were conducted, revealing The climatic change records the time limit to 250,000 years ago, the average resolution of oxygen isotope samples was 150 ~ 300a. The results show that the epoch-making events of stalagmite that correspond to the records of glacial epochs and epochs in the ocean are 11.3kaB.P., 129.3 kaB.P. and 242.5kaB.P. respectively. The age and duration of the boundaries corresponding to the stages of marine isotopes MIS1 ~ MIS7 are also accurately defined by stalagmite records. In addition, the fluctuation processes and changes of the East Asian monsoon climate over the past 250,000 years are also revealed. The comparability of the 250,000-year climate in the Qian-Gui area with that of the deep-sea oxygen isotopes on a thousand-year scale and with the variation of the solar radiation energy in the summer of N65 ° shows the regularity of the climate change in the ancient monsoon in Asia. It is also affected by changes in orbital parameters Cycle and the global ice volume driven by changes.