新月形沙丘形态的模拟实验研究  

SIMULATED STUDY ON BARCHAN DUNE FORMS

作　　者：凌裕泉[1,2,3] 吴正[1,2,3] 刘绍中[1,2,3] 李长治[1,2,3] 

机构地区：[1]中国科学院兰州沙漠研究所 [2]华南师范大学 [3]中国科学院成都计算机应用研究所

出　　处：《地理科学》1998年第1期88-93,共6页Scientia Geographica Sinica

基　　金：国家自然科学基金

摘　　要：新月形沙丘是风沙地貌基本形态之一，一般为高浓度非饱和风沙流所塑造。其形成过程始于风沙运动的“波粒二重性”，并经历沙物质积累（高浓度饱和风沙流）和形体塑造（高浓度不饱和风沙流）两个发育阶段，即耗散性增大和色散性减小过程；非沙质床面零星分布的单个新月形沙丘具有明显的移动性和形态的不稳定性（高大新月形沙山除外）。风洞实验条件下形成的新月形沙丘形态（其尺度比床面沙纹大一个数量级），有助于新月形沙丘形成机制的了解。Barchan dunes is a fundamental pattern of aeolian landform. Generally speaking, it is moulded by non saturated wind sand flow which is the high concentration. Its fomating process is caused by the wave grain duality of sand grain movement, and develop with two stages: sand material accumulation (high concentration saturated wind sand flow) and form moulding (high concentration non saturated wind sand flow), which shows the increase of dissipation and the decrease of dispersion. The scattered single barchan dunes on the non sand bed possess movability and form unstability except the high large crescent sand mountain. In wind tunnel, the formation of crescent dune form(its size is bigger one order of magnitudes than the ripples on the sand bed) will be helpful to understand the formation mechanism of the barchan dunes.

关 键 词：新月形沙丘 模拟实验 耗散性 色散性 沙丘 

分 类 号：P931.3[天文地球—自然地理学]