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基于黔北石膏洞两支石笋(SG1和SG2)的12个高精度230Th年龄(误差为±2.5～55a)和479个氧同位素数据,建立了全新世9.9kaBP(相对1950AD)至今较高分辨率的东亚季风和印度季风交汇区季风降水序列.石膏洞δ18O记录表明:9.9～6.6kaBP,季风降水处于降水丰沛的湿润期;6.6～1.6kaBP,该时段为降水逐渐减弱时期;1.6kaBP至今石笋δ18O最为偏正,季风降水整体处于较弱期,其长期演变趋势整体追随30°N夏季太阳辐射能量变化曲线.利用时序分析方法,对石膏洞与已发表的高分辨率石笋δ18O记录分析发现,石笋所揭示的全新世适宜期结束时间在不同季风区存在显著差异:统计分析结果显示印度季风区的阿曼为7.2～7.4kaBP,东亚季风下的华中地区为5.6～5.8kaBP,而地处于两季风交汇处的西南一带则介于其中约为6.6～7.0kaBP.我们认为供应东亚季风水汽来源的热带西太平洋海水表面温度变化,是可能造成亚洲不同地区全新世适宜期结束时间不一致的原因.
Based on 12 high-accuracy 230Th ages (± 2.5 ~ 55a) and 479 oxygen isotope data from two stalagmites in northern Guizhou gypsum cave (SG1 and SG2), the Holocene 9.9kaBP (relative to 1950AD) The monsoon series of the East Asian monsoon and the Indian monsoon intersects with the monsoonal series of precipitation.The δ18O records of gypsum cave show that the monsoon precipitation is in the period of abundant rainfall from 6.6 to 1.6 kaBP and the period of precipitation is gradually weakened from 9.9 to 6.6 kaBP, The monsoon precipitation is in the weaker period and its long-term evolution trend follows the curve of 30 ° N summer solar radiation energy.Using time series analysis, the δ18O records of the gypsum cave and the published high resolution stalagmite show that stalagmite The results show that there are significant differences in the end-of-fit period of the Holocene between different monsoon regions. Statistical analysis shows that the Oman ranged from 7.2 to 7.4kaBP in the Indian monsoon region and from 5.6 to 5.8kaBP in the Central Asian region under the East Asian monsoon, Southwest China is located between about 6.6 ~ 7.0kaBP. We believe that the supply of East Asian monsoon water vapor source of the tropical West Pacific surface water temperature is likely to cause sub-Asia Reasons for the discrepancy time in different parts of the Holocene Optimum end.