中全新世云南寻甸地区气候演化与冷干事件的石笋记录

通过对云南寻甸XR1石笋进行TIMS-U系测年、氧碳同位素和沉积速率变化分析,重建了寻甸地区中全新世季风气候演化模式:(1)8.0～6.0 ka BP为温暖湿润期;(2)6.0～5.1 ka BP为气候突变期,温湿向冷干转变;(3)5.1～2.1 ka BP为气候恢复期,气候从冷干逐渐恢复到中全新世正常的气候水平.XR...

Stalagmite Records of Climate Change and Cold-Dry Events During the Middle Holocene in Xundian, Yunnan

Based on age-dating of TIMS-U series and analyzing carbon and oxygen isotopes and deposition velocity on XR1 stalagmite from Xianren cave in Xundian,Yunnan,the authors revealed the monsoon climate change pattern during the middle Holocene in Xundian.The climate change in Xundian can be divided into three periods approximately:(1) 8.0～6.0ka BP was a warm and wet period;(2) 6.0～5.1ka BP was a climate change period,with climate changing from wet and warm to cold and dry;(3) 5.1～2.1ka BP was a climate recovering period,during which the climate changed from cold and dry to the average climate level of the Middle Holocene.The authors also detected four clod and dry climate events during the Middle Holocene in Xundian,which perfectly responded to the global change.The first climate event that lasted from 6.0 ka BP to 5.1ka BP corresponded to the cold period during the Middle Yangshao age in archaeology,and is also called the second little ice age by Denton.The second climate event whose age span was from 4.7ka BP to 4.5ka BP was a short cooling event during the climate recovering period.The third cooling event that lasted from 3.1kaBP to 2.5ka BP was called Xizhou Cold period in Chinese history,which was equivalent to the third new ice age in Northern Hemisphere.The cooling event during 2.5ka BP to 2.1ka BP corresponded to the second cold period during the past 5000 years’ climate change in China.