地质学报2017，Vol.91Issue(11)：2545-2556,12.
西藏昌都崩勒溶洞石笋7ka BP以来高分辨δ18O、δ13C记录的气候变化
Climate Change since 7 ka BP Revealed by a High-Resolution Stalagmite δ18O and δ13C Record from Benle Cave in Chamdo, Tibet
摘要
Abstract
High-precision 230Th dating and carbon and oxygen isotopic analysis were carried out on stalagmite from Benle Cave in Chamdo,Tibet Plateau to establish a mid-Holocene paleoclimate change record in Chamdo of Tibet since 7 ka BP.Carbon and oxygen isotopic records of stalagmite reveal that the climate evolution since mid-Holocene (about 7 ka BP) in Chamdo,Tibet can be approximately divided into three climatic periods.① Warm period of 7000～4500 a BP,during which the overall climate was warm and humid,with temperature slowly cooling.② Temperature falling period of 4500 ～ 2300 a BP.As the temperature continued cooling,the climate became dry.③ Temperature rising period of 2300 a BP,during which the air temperature and precipitation fluctuated and were rising.Carbon and oxygen isotope records of stalagmite show that since the middle Holocene the climate changed from warm and humid,rapidly falling temperature and drought,and to strong fluctuating and rising in the study area.A comparative analysis of isotope records of stalagmite in Dongge cave indicates that the slop and fluctuating amplitudes of δ18O curves of stalagmite in Benle cave are significantly higher than that of stalagmite in Dongge cave.The results above suggest that the climate fluctuation and temperature change in the monsoon region of Eastern Qinghai Tibet Plateau was consistent with that in global,and the isotope record of stalagmite in plateau was more sensitive to climate change.The trend of climate change reflected by the isotope record of stalagmite in Chamdo was positively related to summer solar radiation intensity in low latitude areas,and this indicates that the variation of the solar radiation intensity was an important driving factor in the monsoon area in the Tibetan plateau.关键词
青藏高原/崩勒溶洞/石笋/δ18O/δ13C/气候变化Key words
Tibetan Plateau/Benle cave/stalagmite/δ18O, δ13C/climate change引用本文复制引用
韩建恩,邵兆刚,程海,孟宪刚,王津,余佳,杨朝斌,孟庆伟,胥彪..西藏昌都崩勒溶洞石笋7ka BP以来高分辨δ18O、δ13C记录的气候变化[J].地质学报,2017,91(11):2545-2556,12.基金项目
本文为中国地质调查局项目(编号12120113006100、121201104000150009和1212011087114)和中国地质科学院项目(编号YYWF201511)资助的成果. （编号12120113006100、121201104000150009和1212011087114）
