泥石流堆积扇的发育与演化
文献类型：学位论文
| 作者 | 陈杰 |
| 学位类别 | 博士 |
| 答辩日期 | 2005 |
| 授予单位 | 中国科学院研究生院 |
| 授予地点 | 北京 |
| 导师 | 崔鹏 |
| 关键词 | 泥石流 堆积扇 演化 沟道变迁 数值模拟 蒋家沟 |
| 学位专业 | 自然地理 |
| 中文摘要 | 研究了泥石流堆积扇的短期和长期演化机制。首先，通过分析泥石流堆积扇形成的各种控制条件以及它们的特征，建立了堆积扇发育的概念架构。即各种环境背景因素可以归纳为流域内特征和堆积区特征。一是通过流域内的泥石流形成条件和搬运条件控制堆积扇体系，二是通过堆积区的堆积条件影响堆积扇的形成。以小江流域为例，通过使用卫星遥感图片和地形图识别堆积扇范围，以及统计相应的流域特征，对堆积扇的控制因素与堆积扇的关系进行了分析。第二，在野外观测和测量的基础上，研究了堆积扇的短期演化特征。短期演化以泥石流在堆积扇上的自由扩散堆积为基础，同时受到扇面上微地形和沟道发育的影响，其发育过程包括泥石流流向的摆动和堆积厚度的增长。初步分析了以输沙量为基础来预测泥石流的堆积范围；根据泥石流运动方程和固液两相流理论以及流团模型理论，建立并应用了泥石流堆积过程的数值模型，以蒋家沟实际堆积情况进行了模拟和验证。第三，以蒋家沟为例，结合历史资料和实地测量，研究了泥石流堆积扇上沟道的变迁。随着泥石流在下游沟道的淤积，泥石流容易从弯道凹岸处冲出沟道而进入扇面，产生扩散堆积并自动寻找新的更低的流路。堆积扇上沟道迁移的频度受到不同泥石流性质、规模以及它们的暴发频度和顺序等的影响。在堆积扇的沟道变迁规律基础上，分析了堆积扇的中长期演化规律。第四，将泥石流堆积扇作为一个系统来考察，则它具有本身固有的一些属性，特别是堆积范围和形态；同时泥石流堆积扇作为整个流域侵蚀产沙的结果，它对上游输入条件的变化十分敏感。即泥石流堆积扇存在内在的临界条件和外在的临界条件。分别讨论了泥石流堆积扇对地质条件、气候条件和人类活动条件改变时的响应。本论文的创新点在于提出了泥石流堆积扇研究的概念架构，在此基础上分析了堆积扇发育的各种控制因素和作用方式，各种环境条件变化时堆积扇的响应；初步研究了泥石流堆积扇短期演化和长期演化的特征和主导因素。 |
| 英文摘要 | The development of debris flow fans in the short term and in the long term was researched. Firstly, through analyzing the controlling conditions and their characters, a frame work of development system of debris flow fans was established. These conditions were sorted as inner-drainage basin and deposition area. They influence debris flow fan respectively through controlling the initiation and transportation of debris flow and through forming the local landform of deposition. Taking the Xiaojiang ravine as an example, using TM images and topographic maps to examine debris flow deposited scope, and collecting the corresponding drainage parameters, the relationship between the controlling conditions and the debris flow fans was analyzed. Secondly, debris flow fan development in short term was studied based on field observation and survey. The short-term development was basically that debris flow overspread and deposited freely on the surface and was influenced by the tiny landform and the channel existing on deposition area. The development included the swing of flow direction and the accretion of deposition thickness. Sediment discharge was used to estimate the deposition scope. And a numeric model of debris flow deposition was established to simulate a real deposition event in Jiangjia gully. Thirdly, the channel avulsion on debris flow fan was studied in Jiangjia Gully. When debris flow deposition in channel caused the height of channel bed raised enough, the debris flow rushed out from the outside of the bend. While debris flow moved along the new low lands down stream, it would incise a new channel with bigger gradient and less length. The rate of channel avulsion depended on various properties, frequency, magnitude and even the succession of debris flows. On the basis of the regularity of channel avulsion, the development of debris flow fans in the longer scale was analyzed.Fourthly, if debris flow fan was considered as a system, it had some intrinsic characters, in particular the scope and shape. On the other hand, as a result of erosion and sediment yield of the drainage area, debris flow fan was very sensitive to the change of the input from upstream. There were some intrinsic thresholds and extrinsic thresholds in the geomorphic development of debris flow fans. The debris flow fans response to the change of geology, climate, and human activities were discussed separately. |
| 学科主题 | 灾害学 |
| 语种 | 中文 |
| 公开日期 | 2012-01-04 |
| 源URL | [http://192.168.143.20:8080/handle/131551/3677]  |
| 专题 | 成都山地灾害与环境研究所_成都山地所知识仓储（2009年以前） |
| 推荐引用方式 GB/T 7714 | 陈杰. 泥石流堆积扇的发育与演化[D]. 北京. 中国科学院研究生院. 2005. |
入库方式： OAI收割
来源：成都山地灾害与环境研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。