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### 毛乌素沙漠东南缘滴哨沟湾剖面DGS1层段粒度特征及其指示的全新世气候变化

1. 1. 华南师范大学地理科学学院, 广东 广州 510631
2. 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室, 陕西 西安 710061
3. 惠州学院旅游系, 广东 惠州 516007
4. 广西师范学院规划与地理科学学院, 广西 南宁 530001
• 收稿日期:2014-12-05 修回日期:2015-03-16 出版日期:2016-03-20 发布日期:2016-03-20
• 作者简介:

舒培仙（1990-）,男,安徽宣城人,博士研究生,主要研究方向为地表过程与第四纪环境演变。E-mail: shupeixian@163.com

• 基金资助:
国家重点基础研究发展计划（973计划）（2013CB955903）项目、国家自然科学基金（41471159）项目资助

### Climate Variations Recorded by the Grain-size from the DGS1 Segment in the Southeast of China′s Mu Us Desert During the Holocene

Peixian Shu1,2(), Baosheng Li1,2(), Dongfeng Niu1, Fengnian Wang3, Xiaohao Wen1, Yuejun Si4, Qiong Chen1

1. 1.School of Geography, South China Normal University, Guangzhou 510631, Guangdong, China
2.State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, Shaanxi, China
3.Tourism department, Huizhou University, Huizhou 516007, Guangdong, China
4.School of Geography and Planning, Guangxi Teachers Education University, Nanning 530001,Guangxi, China
• Received:2014-12-05 Revised:2015-03-16 Online:2016-03-20 Published:2016-03-20
• Supported by:
National Basic Research Program of China (2013CB955903), National Natural Science Foundation of China (41471159)

Abstract:

The DGS1 segment in the Dishaogouwan section from the Salawusu River valley is a typical stratum to study the climate variations in the Holocene. Based on the dating ages and analysis of the grain-size features within the DGS1,we find that the particle gradually becomes finer but the sorting rate becomes poorer from mobile dune sands, peat, paleosols, semi-fixed sand dunes to the lacustrine facies and secondary loess; the grain-size parameter values of Mz(?), σ1(?), SK1 in the dune sands are lower than those in the lacustrine facies or secondary loess, and the KG value shows opposite trends; the Mz ranges from 2.26 to 3.36 (average 2.55) in the dune sands, 2.33 to 6.33 (average 4.28) in the lacustrine facies and 4.25 to 5.27 (average 4.58) in the secondary loess; the σ1(?) ranges from 0.51 to 2.51 (average 0.97) in the dune sands, 0.81 to 3.25 (average 2.13) in the lacustrine facies and 1.10 to 2.46 (average 1.46) in the secondary loess; the SK1 ranges from 0.01 to 0.45 (average 0.29) in the dune sands, 0.09 to 0.53 (average 0.32) in the lacustrine facies and 0.22 to 0.38 (average 0.36) in the secondary loess; the KG ranges from 0.92 to 1.70 (average 1.42) in the dune sands, 0.65 to 1.80 (average 1.13) in the lacustrine facies and 1.22 to 1.51 (average 1.44) in the secondary loess. They display distinct variations that correspond to the sedimentary changes. The surface microstructure of the quartz grains in the lacustrine facies under the electron microscope scanning shows typical aeolian characteristics with good roundness, without precipitated silica, but with pits on the surface. Together with the freshwater gastropod fossils discovered in the stratigrapgical layers, we suggest that the grain-size cycles in the DGS1 segment actually reflect the climate variations in the alternation of East Asian winter and summer monsoons in the Holocene, and the climate of the Holocene can be divided into four stages: the warming period of the Early Holocene; Holocene heyday; the fluctuation period from the Megathermal to cold; and the cooling period of instability and desertification. The climate changes in the DGS1 during the Holocene correspond well to those found in the North Atlantic and some places in China, which probably results from the global climate changes in the Holocene.

• P532