靖边黄土剖面记录的末次冰期以来的气候变化  

Climate change since the last glacial stage recorded in Jingbian loess section

作　　者：王攀[1] 张培新 杨振京[1] 石迎春[1] 宋超[1] 郭娇[1] WANG Pan;ZHANG Peixin;YANG Zhenjing;SHI Yingchun;SONG Chao;GUO Jiao(Institute of Hydrogeology and Environmental Geology,Chinese Academy of Geological Sciences,Shijiazhuang 050061,China;China University of Mining and Technology-Beijing,Beijing 100083,China)

机构地区：[1]中国地质科学院水文地质环境地质研究所,石家庄050061 [2]中国矿业大学(北京),北京100083

出　　处：《海洋地质与第四纪地质》2019年第3期162-170,共9页Marine Geology & Quaternary Geology

基　　金：中国地质科学院水文地质环境地质研究所基本科研业务费项目“靖边地区次生黄土研究与极端气候识别”(SK201310);中国地质科学院基本科研业务费项目“西北干旱半干旱地区表土孢粉研究及数据库建设”(YYWF201627);中国地质调查局地质调查大项目“中国气候变化黄土沉积记录研究”(12120113005900)

摘　　要：靖边黄土剖面位于黄土-沙漠的过渡区,能更加敏感地记录第四纪东亚季风气候变化。对位于靖边县南15km的三道沟黄土剖面(0~7.2m)进行年代学、磁化率、粒度、元素地球化学分析,粒度数据显示靖边黄土剖面沉积物以粉砂为主,占比高达80%以上;年龄曲线显示靖边黄土剖面存在千年尺度的沉积间断;元素地球化学数据表明,古土壤向黄土层中的元素迁移顺序为Ca>Na>Mg>Si>Al>K>Fe,剖面黄土处于初级风化阶段;多指标综合分析表明,靖边黄土剖面末次冰期以来的气候变化经历了MIS3气候相对温暖湿润且震荡激烈、末次冰盛期气候极度冷干、冰消期气候好转和全新世气候温暖湿润4个阶段。The Jingbian loess section is located in the transition zone between the loess plateau and desert,which is more sensitive than others to the Quaternary East Asian monsoon climate changes.The analyses of chronology,susceptibility,grain size and geochemical elements of the loess section in the south of Jingbian county were carried out.The Jingbian loess is a kind of eolian deposits composed of more than 80%of silty sand.Dating age suggests that there is a millennial scale sedimentary discontinuity in the section.The chemical data shows that the loess is in a primary weathering stage and the element abundance is in an order of Ca>Na>Mg>Si>Al>K>Fe.The comprehensive multi-index analyses suggest that the loess section has suffered four stages of climatic changes since the Last Glacial Period.The MIS3 was relatively warm,humid and oscillated.The Last Glacial Maximum was extremely cold and dry.The Last Deglaciation was under an improving climate condition and the Holocene warm and humid.

关 键 词：磁化率 粒度 元素 气候变化 靖边黄土 

分 类 号：P532[天文地球—古生物学与地层学] P595[天文地球—地质学]