中国北方部分地区黄土、沙漠沙、湖泊、河流细粒沉积物粒度多组分分布特征研究
- 中国科学院地质与地球物理研究所 北京 100029
- 收稿日期:
1900-01-01
- 修回日期:
1900-01-01
- 刊出日期:
2009-04-10
摘要: 通过对我国北方部分地区的黄土、沙漠沙、湖泊、河流细粒沉积物的粒度多组分分布特征系统研究后总结了其粒度分布特征及组分间差异，并提出了风成、水成沉积物成因类型的判别依据。认为：1)细粒沉积物粒度一般由多个组分叠加构成，表现为多组分粒度分布特征。2)黄土粉尘粒径以<70 μm的悬浮颗粒为主，粒度由粗、中、细三个组分构成。粗粒组分含量最高，其中值粒径与源区距离呈负相关，中粒组分百分含量与源区距离呈正相关。3)沙漠沙粒度由一个极其明显的粗粒跳跃组分构成，中值粒径一般位于100~300 μm，分选性极好。4)湖泊沉积物粒度分布最多可有6个组分(中值粒径：<1 μm，2~10 μm，10~70 μm，70~150 μm，150~700 μm，>700 μm)，前4个组分属悬浮组分，⑤为跳跃组分，⑥为滚动组分，分选性差。5)河流沉积物粒度分布曲线较复杂，其分布特征蕴含了水动力强弱信息。6)沙漠沙→黄土与河流沙→湖泊沉积物其优势组分的粒径均逐渐变细，但水成相对应组分比风成组分粒径要粗.
The Multimodal GrainSize Distribution Characteristics of Loess, Desert, Lake and River Sediments in Some Areas of Northern China
- Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029
- Received Date:
1900-01-01
- Rev Recd Date:
1900-01-01
- Publish Date:
2009-04-10
Abstract: By using highresolution laser grain size instrument Mastersizer 2000, the multimodal characteristics of grain size distribution of loess, desert, lake and river sediments are measured and carefully studied. The standard patterns and their grain size characteristics of various sediments are systemically summarized, the discrepancies of multimodal distribution among these sediments are concluded and the comparisons of grain size multimodal distribution of them are also discussed in this paper. The major conclusions are followed: 1)The multimodal characteristic of grain size distribution is a common feature in all sediments and results from properties of transportation medium, dynamic intensity, transportation manner and other factors; 2) There are three modes in loess grain size distribution: fine, median and coarse (the median size is <1 μm,1～10 μm,10～70 μm, respectively) and suspended particles which diameters are less than 70 μm are dominant; 3) There is a predominant coarse saltation mode in grain size distribution of sandy dunes, which median size is about 100～300 μm and the content is larger than that of other modes; 4) There are 6 modes (median size are <1 μm, 2～10 μm, 10～70 μm, 70～150 μm, 150～700 μm, >700 μm respectively) in grain size distribution of lake sediments. The former 4 modes are suspense and others are saltated and rolling. Lake sediments can be divided into three types: lake shore facies, transitional facies and central lake facies; 5) The grain size distribution of river sediments is the most complex and it's consist of suspension, saltation and rolling modes.6) The windblown depositions and aqueous sediments of predominant mode gradually decreases form sandy dunes to loess and river to lake sediments. But the grain size of modes of windblown depositions is usually finer than that of corresponding modes of aqueous sediments.
殷志强. 中国北方部分地区黄土、沙漠沙、湖泊、河流细粒沉积物粒度多组分分布特征研究[J]. 沉积学报, 2009, 27(2): 343-351.
| 引用本文: |
殷志强. 中国北方部分地区黄土、沙漠沙、湖泊、河流细粒沉积物粒度多组分分布特征研究[J]. 沉积学报, 2009, 27(2): 343-351.
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YIN Zhiqiang. The Multimodal GrainSize Distribution Characteristics of Loess, Desert, Lake and River Sediments in Some Areas of Northern China[J]. Acta Sedimentologica Sinica, 2009, 27(2): 343-351.
| Citation: |
YIN Zhiqiang. The Multimodal GrainSize Distribution Characteristics of Loess, Desert, Lake and River Sediments in Some Areas of Northern China[J]. Acta Sedimentologica Sinica, 2009, 27(2): 343-351.
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