末次冰期中以H和D/O事件为代表的一系列百年——千年时间尺度的气候突变事件的发生和终止时间，是精确建立该时期全球气候变化历史的重要参考点；也是进一步探讨全球各气候系统相互联系的基础。然而由于测年方法以及各地质记录本身的原因，导致对这些气候事件的精确标定尚需完善。. 本研究以重庆地区238U浓度高达10 ppm的石笋样品，获取高精度的U系年龄结果，结合石笋薄片的纹层计数，建立高精度的年代标尺；利用Micro-mill微区取样技术获取高分辨率的氧碳稳定同位素记录，结合微量元素微区原位分析测试，进行高分辨率的古气候重建。通过与其他记录的详细对比研究，为末次冰期期间古气候记录全球对比的年代标尺提供新的参考；深入研究亚洲夏季风变化与全球气候变化的相位关系和模式，进而探讨亚洲夏季风变化机理。

A series of abrupt climatic events on the centennial-millennial timescale, such as the Heinrich (H) and Dansgaard-Oeschger (D/O) events have been the most prominent characteristic of global climate changes during the Last Glacial Period (LGP). The timing of the onset and termination of these events has been taken as the essential “tie points” in the comprehensive reconstruction of global climate changes during the LGP, which is very important for the exploration of the correlation between different climatic systems. But the precise calibration of these events is still uncompleted because of the problems of dating methods and the nature of different geological archives.. In this proposal, stalagmites collected in Chongqing, China, with the concentration of 238U as high as ~10 ppm, will be used to yield high quality 230Th dating results. High precise chronology will be built based on the 230Th dating and annual-layer counting for the stalagmites. With the help of the Micro-mill drilling instrument and situ micro-zone elements analysis, high resolution records of Asian summer monsoon during the LGP will be reconstructed by the proxies of δ18O and Mg/Ca, Sr/Ca ratios. This work will contribute new reference to the chronology calibration for the global comparison of paleoclimate change during the LGP, via the completely contrastive study between our stalagmite inferred records of Asian summer monsoon and the others. Furthermore, the phase relationships and the patterns of climate change between the Asian summer monsoon and other regions will be studied thoroughly, and then the dynamic mechanism for the evolution of Asian Summer monsoon will be investigated.