地理科学 ›› 2018, Vol. 38 ›› Issue (5): 818-826.doi: 10.13249/j.cnki.sgs.2018.05.020

• • 上一篇    

六盘山东麓晚更新世以来黄土粒度指示的物源特征及演变

王兆夺(), 黄春长(), 杨红瑾, 庞奖励, 查小春, 周亚利   

  1. 陕西师范大学地理科学与旅游学院, 陕西 西安 710119; 陕西师范大学/地理学国家级实验教学示范中心, 陕西 西安 710119
  • 收稿日期:2017-06-02 修回日期:2017-11-04 出版日期:2018-05-10 发布日期:2018-05-10
  • 作者简介:

    作者简介:王兆夺(1984-), 男,甘肃会宁人, 博士研究生, 研究方向为资源开发与环境演变。E-mail:joedonwang@163.com

  • 基金资助:
    国家自然科学基金项目(41771110,41601020)、中央高校基本科研业务费专项基金(GK.201704013)资助

Loess Provenance Characteristics and Evolution Indicated by Grain Size Since Late Pleistocene at the Eastern Foot of Liupan Mountains,China

Zhaoduo Wang(), Chunchang Huang(), Hongjin Yang, Jiangli Pang, Xiaochun Zha, Yali Zhou   

  1. School of Geography and Tourism, Shaanxi Normal University, Xi’an 710119, Shaanxi, China; National Demonstration Center for Experimental Geography Education, Shaanxi Normal University, Xi’an 710119, Shaanxi, China
  • Received:2017-06-02 Revised:2017-11-04 Online:2018-05-10 Published:2018-05-10
  • Supported by:
    National Natural Science Foundation of China (41771110, 41601020), the Fundamental Research Funds for the Central Universities(GK.201704013)

摘要:

在宁夏长城塬完整的晚更新世-全新世黄土-古土壤剖面(长城塬剖面)进行高分辨率采样,对125个样品的粒度数据做了粒度端元分析,并对各端元组分含量在地层深度尺度上做了小波分析。结果认为:端元分析法可以把代表4种不同动力的沉积端元分离出来。端元1可能代表了西风带控制下的由高空气流搬运的远源粉尘物质;端元2可能代表了沉积物沉积后在东亚夏季风作用下的风化以及成壤改造作用;端元3可能代表了后期的淋溶作用动力特征;端元4可能代表了东亚冬季风作用下典型的风成黄土粗颗粒组分特征。根据小波分析认为各端元组分含量在不同的深度上均存在着准周期变化,指示了相对应的时间尺度上古季风变化具有准周期性的特征,同时也说明了沉积剖面一直处于较为连续沉积状态,比较完整地记载了各沉积动力过程。各端元组分在不同的时间尺度上具有不同的准周期性特征。

关键词: 全新世古气候, 黄土-古土壤, 粒度, 端元分析, 小波分析

Abstract:

This article makes End Member analysis on grain-size data collected from high resolution 125 samples based on typical Late Pleistocene-Holocene Loess-Paleosol profile (CCY profile) in Changchengyuan, Ningxia Province, and do the wavelet analysis for the End Members components on the axis in depth. The research result shows that four End Members can be separated from the sediment grain sizes in CCY profile. And the EM1 may indicate dust from far source under the high-altitude airflow controlled by westerly belt. The EM2 may indicate dynamic strength of sedimentation under the influence of weathering and pedogenesis. The EM3 may represents the eluviation dynamic characteristic. The EM4 may indicates the northwest monsoons typical eolian loess under the influence of component characteristics. According to the wavelet analysis, it can be concluded that the component content of each dynamic of End Member has periodic variation at different depths, which indicates that the corresponding time scale of the paleomonsoon variation has periodic characteristics, and also indicates that the sedimentary profile has been in a continuous and uninterrupted sedimentary state, and the sedimentary dynamic processes are recorded completely. Each End Member component has different periodic characteristics on different depth (time) scales.

Key words: Holocene palaeoclimate, Loess-paleosol, grain size, End Member analysis, wavelet analysis

中图分类号: 

  • F129.9