| 西藏安多剖面沉积物粒度特征及环境意义 |
| |
| 引用本文： | 黄文敏,伍永秋,潘美慧,张健枫,杜世松.西藏安多剖面沉积物粒度特征及环境意义[J].中国沙漠,2014,34(2):349-357. |
| |
| 作者姓名： | 黄文敏 伍永秋 潘美慧 张健枫 杜世松 |
| |
| 作者单位： | 1. 北京师范大学 防沙治沙教育部工程研究中心/减灾与应急管理研究院, 北京 100875;2. 西北师范大学 地理与环境科学学院, 甘肃 兰州 730070 |
| |
| 基金项目： | 国家自然科学基金项目(41071129);国家重点基础研究发展计划项目(2013CB956001)资助 |
| |
| 摘 要： | 对西藏安多剖面的3个层位沉积物与两个现代流动沙丘表层沉积物粒度组成、传统粒度参数及体积分维值进行了对比分析，探讨其粒度特征以及环境指示意义。结果表明：安多剖面的3层代表了3个不同的气候阶段，第一层（0～172 cm）沉积动力为风，其中在0.44～1.08 m深度处是一次风力加强的阶段，第二层（172～224 cm）、第三层（224～232 cm）均在6 Φ附近出现次峰，悬浮组分明显增加，推断为远距离输送的粉砂级颗粒沉降，表明这两个阶段风力有所减弱；安多剖面颗粒比研究区现代流动沙丘颗粒细，表明剖面可能为固定或半固定沙丘沉积；本研究区样品的体积分维值在0.215～1.77，虽然没有实际的物理意义，但作为粒度参数指标，在指示环境变化上是有效的，并且与粘粒、粉砂含量呈现明显的正相关关系，与细砂呈现明显的负相关关系。
|
| 关 键 词： | 粒度 分维值 风成沉积 安多 |
| 收稿时间： | 2013-06-17; |
| 修稿时间： | 2013-07-24 |
Grain Size Characteristics and Its Environmental Significance of the Amdo Profile in Tibet,China |
| |
| Huang Wenmin,Wu Yongqiu,Pan Meihui,Zhang Jianfeng,Du Shisong.Grain Size Characteristics and Its Environmental Significance of the Amdo Profile in Tibet,China[J].Journal of Desert Research,2014,34(2):349-357. |
| |
| Authors: | Huang Wenmin Wu Yongqiu Pan Meihui Zhang Jianfeng Du Shisong |
| |
| Institution: | 1. MOE Engineering Center of Desertification and Blown-sand Control/Ministry of Civil Affairs & Ministry of Education Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China;2. College of Geography and Environment Science, Northwest Normal University, Lanzhou 730070, China |
| |
| Abstract: | By analyzing the grain size component, traditional grain size parameters and volume fractal dimensions of three different layers of the Amdo profile in Tibet of China and two modern mobile sand dunes, the grain characteristics and environmental significance of the Amdo profile are discussed. The results showed that the three layers represent three different climatic phases. The first layer (0-172 cm) deposits of the Amdo profile are aeolian origin and the wind has strengthened at depth of 44-108 cm. Sediments grain size curves of the second layer (172-224 cm) and the third layers (224-232 cm) show that almost all samples have a second peak at 6 Φ, that means the increasing of the suspension component and a long distance transportation of silt particle sedimentation, indicating the weakening of wind force in this phases. Compared with the modern mobile sand dunes, all the samples from the Amdo profile are finer, which imply that the Amdo profile is likely to be a fixed dune or semi-fixed dune. Fractal dimension (D) of all the studied samples is 0.215-1.77, losing physical meaning in Euclidean 3D space, but the D value is still significant to indicate the environmental change. Volume fractal dimensions have a notable positive correlation with the content of clay and slit, negatively correlated with the content of fine sand. |
| |
| Keywords: | grain size fractal dimension aeolian sediments Amdo |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《中国沙漠》浏览原始摘要信息 |
| 点击此处可从《中国沙漠》下载免费的PDF全文 |
|
