末次间冰期以来渭河上游气候演化的黄土记录研究  

Loess Record of Environment Changes in Upper Reaches of Weihe River since Last Interglacial

作　　者：张慧[1] 潘保田[1] 徐树建[1] 管清玉[1] 苏怀[1] 刘小锋[1] 

机构地区：[1]兰州大学西部环境教育部重点实验室,甘肃兰州730000

出　　处：《中国沙漠》2007年第2期182-186,共5页Journal of Desert Research

基　　金：国家自然科学基金项目(40401007)资助

摘　　要：对渭河上游樊家台剖面末次间冰期以来黄土地层的粒度与CaCO3进行综合分析表明,末次间冰期时,受夏季风影响较大,粒度较细,CaCO3有较强的淋溶与淀积,气候呈现较为暖湿的特点;末次冰期时,受冬季风影响较强,粒度较粗,CaCO3淋溶淀积微弱,气候较为干冷。间冰期早期(相当于深海氧同位5e阶段)由于夏季风较强,粉尘堆积较少,古土壤向下发育,并与下部土壤融合,导致粒度较5a、5c阶段粗;2阶段的早期,由于粉尘源区出现了高湖面,环境湿度大,造成此时段早期黄土粒度较晚期细;表现出区域气候的特点。Integrated analysis on the median grain size, CaCO3 content in the Fanjiatai loess section in upper reaches of Weihe River suggested that the climate in the Last Interglacial was characterized with warm and wet strongly influenced by summer monsoon, and that in the Last Glacial was cool and dry strongly influenced by winter monsoon. Because the summer monsoon was stronger and the deposition of dust were little during the early of the Last Interglacial（corresponding to the Stage 5e of the marine oxygen isotope records）, the paleosol developed into the underlying layer; the lakes in the dust source had more water, and it induced that the grain size was little during the early of the stage MIS2 than the later; so it shows regional climatic character.

关 键 词：渭河 末次间冰期 黄土 粒度 碳酸钙 气候演化 

分 类 号：P532[天文地球—古生物学与地层学]