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深海氧同位素第3阶段晚期(MIS3a)是青藏高原较为特殊的暖湿时期,为了解这一时期高原东缘的气候变化细节,利用AMS14C定年和粒度、总有机碳、正构烷烃等环境代用指标提取了四川都江堰湖相沉积剖面的相应记录.经过校正后的日历年龄显示此剖面沉积于43.6～34.6kaBP期间,记录了千年尺度的D-O旋回事件,其分布时段分别为:DO11(43.6～41.8kaBP),DO10(41.8～39.2kaBP),DO9(39.2～37.7kaBP),DO8(37.7～35.5kaBP),DO7(35.5kaBP～未见顶).该剖面总有机碳曲线与南京葫芦洞石笋和格陵兰冰心(GRIP)氧同位素曲线的对比表明,该区域气候记录对全球高纬地区的冰量变化和亚洲季风演化具有响应;而中纬度太阳辐射岁差对该区域气候波动的控制作用较强导致了细节上存在差异.
In the late 3rd stage of deep sea oxygen isotope (MIS3a), the Qinghai-Tibet Plateau is a special warm-wet period. In order to understand the climate change details of the eastern edge of the plateau during this period, the AMS14C dating and grain size, total organic carbon and normal paraffin, The corresponding record of the lake facies sedimentary section in Dujiangyan in Sichuan Province was extracted, and the corrected calendar date shows that this section was deposited during the period of 43.6 ~ 34.6 kaBP, and records the DO cycle at the millennium scale with DO11 (43.6 ~ 41.8 kaBP ), DO10 (41.8-39.2kaBP), DO9 (39.2-37.7kaBP), DO8 (37.7-35.5kaBP) and DO7 (35.5kaBP- not seen), respectively.The total organic carbon curve of this section was similar to that of the stalagmite of Gourd Cave in Nanjing and the ice core of Greenland (GRIP) oxygen isotope curve shows that the climate record in this region responds to the change of ice volume in the global high latitudes and the evolution of the Asian monsoon. However, the control effect of mid-latitude solar precession on climate fluctuations in this region is strong, leading to the details has a difference.