干旱区生态环境知识资源中心(Arid): 沙丘形态动力学数值模拟:以真实空间元胞自动机模型(ReSCAL)为例

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	沙丘形态动力学数值模拟:以真实空间元胞自动机模型(ReSCAL)为例
其他题名	NUMERICAL SIMULATION ON SAND DUNE MORPHODYNAMIC: A CASE STUDY OF ReSCAL MODEL
	张德国 1; 杨小平 2
来源期刊	第四纪研究
ISSN	1001-7410
出版年	2017
卷号	37 期号:2 页码:368-379
中文摘要	沙丘研究不再局限于现有沉积状态的描述,而是延伸到其形成发育机理的研究。本文通过ReSCAL沙丘模型的数值模拟分析,获得如下结论:1)ReSCAL沙丘模型实现了风况因素影响下复合型沙丘的形成发育过程,揭示了复合沙丘表面次生沙丘形成与星状沙丘翼角延伸的动力机制,提出了沙丘形态与近地表风况之间的互馈机制对近地表风沙流的影响是次生沙丘出现和星状沙丘翼角延伸的重要原因。2)示踪了沙粒的移动轨迹,发现了沙粒每次在沙丘背风坡的埋藏深度具有随机性,使得沙颗粒的平均埋藏时间不同于以往计算的更新时间,继而发现新月形沙丘沙平均埋藏时间等于纵向最大剖面面积与其对应单宽输沙率的比值。3)基于沙丘脊线走向数学方法的发展,并结合ReSCAL沙丘模型的数值模拟结果,发现双向风况模式下,沙源供应能力的变化不仅能塑造不同的沙丘形态,而且能改变沙丘的生长发育模式,甚至是沙丘臂膀的延伸方向(走向)。
英文摘要	In the recent years,the development of sand dune numerical simulation has provided new opportunities for the desert study. Under this background, dune research is no longer limited to the description of a recent depositional state of dunes, but extended to cover investigation on dune morphodynamics. Based on the numerical results of ReSCAL dune model,the following knowledges are obtained: (1) We simulate dunes formed by unidirectional or multi-directional flow regimes,and demonstrate the morphodynamic of superimposed dune emergence and star dune arms extension. Then, we propose that the effect of a complete mechanism between flow and bed form dynamics on dune surface sand flux might be an important reason to shape the superimposed dune and star dune arms. (2)The renewal time of sand particles can be expressed as the ratio of dune length to its migration velocity. However, by tracking individual cells of a 3D cellular automaton dune model, we discover that the depth at which a particle is buried during avalanches is a random variable and the mean residence time is different from the renewal time. In addition,we also calculate that the mean residence time of sediment particles in barchans is equal to the surface of the central longitudinal dune slices divided by the input sand flux. (3) Based on the development of dune orientation’s theory and the results of ReSCAL dune model, we elucidate that the changes of sand availability not only shape the dune forms, but also affect the dune growth mechanism and dune arms reorientation in bidirectional wind regimes.
中文关键词	沙丘形态动力学 ; ReSCAL沙丘模型 ; 次生沙丘 ; 星状沙丘 ; 平均埋藏时间 ; 风况 ; 沙源供应能力 ; 沙丘脊线走向
英文关键词	dune morphodynamic ReSCAL dune model superimposed bedforms star dune mean residence time wind regime sand availability dune ridge orientation
语种	中文
国家	中国
收录类别	CSCD
WOS类目	GEOLOGY
WOS研究方向	Geology
CSCD记录号	CSCD:5944983
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/235833
作者单位	1.中国科学院地质与地球物理研究所, 中国科学院新生代地质与环境重点实验室, 北京 100029, 中国; 2.浙江大学地球科学学院, 中国科学院新生代地质与环境重点实验室, 杭州, 浙江 310027, 中国
推荐引用方式 GB/T 7714	张德国,杨小平. 沙丘形态动力学数值模拟:以真实空间元胞自动机模型(ReSCAL)为例[J],2017,37(2):368-379.
APA	张德国,&杨小平.(2017).沙丘形态动力学数值模拟:以真实空间元胞自动机模型(ReSCAL)为例.第四纪研究,37(2),368-379.
MLA	张德国,et al."沙丘形态动力学数值模拟:以真实空间元胞自动机模型(ReSCAL)为例".第四纪研究 37.2(2017):368-379.