若尔盖盆地阿米欧拉-南剖面粒度端元特征及其记录的15 ka来气候变化  

Particle endmembers characteristics of Amiola-South profile in the Zoige Basin and recorded climate change since 15 ka BP

作　　者：翟颖 庞奖励 黄春长 查小春 周亚利 李瑜琴 张玉柱[2] 孙雪晴 赵晓康 Zhai Ying;Pang Jiangli;Huang Chunchang;Zha Xiaochun;Zhou Yali;Li Yuqin;Zhang Yuzhu;Sun Xueqing;Zhao Xiaokang(School of Geography and Tourism,Shaanxi Normal University,Xi'an 710119,China;School of Urban and Environment Sciences,Northwest University,Xi'an 710127,China)

机构地区：[1]陕西师范大学地理科学与旅游学院,陕西西安710119 [2]西北大学城市与环境学院,陕西西安710127

出　　处：《中国沙漠》2025年第2期111-118,共8页Journal of Desert Research

基　　金：国家自然科学基金项目(42271046,42277449,41971116)。

摘　　要：选取玛曲县阿米欧拉-南剖面黄土-古土壤序列,对其粒度进行端元分析,结合磁化率和Rb/Sr,试图揭示典型剖面沉积物的沉积学和动力学特征及其与气候演变的关系。结果表明:(1)粒度可划为5个端元组分,EM1为悬移搬运的细颗粒物质及成壤作用产生的黏粒;EM2为气候暖湿时风力对河漫滩物质的搬运作用;EM3是西风和东亚冬季风搬运的砂粒;EM4是强沙尘暴或强冬季风从近源地区搬运的粗颗粒物质;EM5是若尔盖古湖泊的湖滨环境。(2)在阿米欧拉山一带,由于若尔盖古湖湖水退却,在15.5 ka BP前后出露陆地并开始接受稳定的风尘堆积,15.5~8.5 ka BP寒冷干燥,8.5~3.0 ka BP转为温暖湿润,3.0 ka BP至今转为干冷。小波分析表明东亚季风有5.6 ka的主周期和2.1 ka、3.5 ka的次周期旋回。In this study,we selected the loess-paleosoil sequence from Amiola-South profile in Maqu County to analyze its grain size,and combined with magnetic susceptibility and Rb/Sr,in an attempt to reveal the sedimentological and kinetic characteristics of typical profile sediments and their relationship with climate evolution.The results showed that:(1)The particle size was divided into five terminal components:EM1 is the fine particulate matter transported by suspension and the clay particles produced by soil formation;EM2 is the effect of wind on the transport of floodplain materials in warm and humid climates.EM3 is the sand carried by the westerly and East Asian winter winds;EM4 is coarse particulate matter transported from near-source areas by severe sandstorms or strong winter winds;and EM5 is the lakeside setting of the ancient Zoige lake.(2)In the area of Amiola Mountain,due to the retreat of the water of the ancient Zoige lake,the land was exposed around 15.5 ka BP and began to accept stable wind and dust accumulation,15.5-8.5 ka BP was cold and dry,8.5-3.0 ka BP turned warm and wet,and 3.0 ka BP turned dry and cold so far.Wavelet analysis shows that the East Asian monsoon has a main cycle of 5.6 ka and a sub-cycle cycle of 2.1 ka and 3.5 ka.

关 键 词：阿米欧拉-南剖面 湖滨 风积物 粒度端元 气候变化 

分 类 号：P535[天文地球—古生物学与地层学]