颗粒波纹粒度特征——以敦煌雅丹、三垄沙和托克逊地区为例  

Study on the grain size characteristics of granule ripples:Taking Dunhuang Yardang,Sanlongsha and Tokexun areas as examples

作　　者：周坤 韩庆杰 屈建军 俎瑞平 刘冰 Zhou Kun;Han Qingjie;Qu Jianjun;Zu Ruiping;Liu Bing(Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing100049,China)

机构地区：[1]中国科学院西北生态环境资源研究院干旱区生态安全与可持续发展重点实验室,甘肃兰州730000 [2]中国科学院大学,北京100049

出　　处：《中国沙漠》2025年第1期44-54,共11页Journal of Desert Research

基　　金：国家自然科学基金项目(41001005,41771010,42071048);国家重点研发计划项目(2022YFB4202102);宁夏沙坡头规模化防沙治沙试点项目生态监测工程(宁沙管合字[2021]8号)。

摘　　要：粒度特征是颗粒波纹系统研究的基础,也是深入认识其几何形态和发育过程的前提。通过大样本调查取样及室内实验,分析了敦煌雅丹、三垄沙和托克逊颗粒波纹沉积物的粒度特征。结果表明:(1)颗粒波纹主要分布在4种小尺度地形:戈壁起伏地形、雅丹廊道、台地(雅丹台地和山麓剥蚀台地)和沙丘迎风坡;(2)波峰表面粒度特征参数具有规律性:平均粒径越大,分选程度越好,粒度频率分布曲线越接近对称,峰值越宽平;(3)不同于波峰最粗、波谷最细的以往认识,我们发现表面粒度在迎风坡接近波峰位置处达到最粗,在背风坡接近波谷位置处达到最细;(4)剖面混合层中相似层理的粒度特征相近,且表现出随着层理加深粒径变细的规律。The grain size characteristics are the basis for the study of granule ripple systems and the prerequisite for a deeper understanding of their morphological and developmental processes.In this paper,the grain size char-acteristics of granule ripple sediments in Dunhuang Yardang,Sanlongsha and Xinjiang Tokexun areas were anal-ysed through large-sample survey and indoor experiments.The results indicate that granule ripples are primarily distributed in four small-scale terrain types:the gobi undulating terrain,yardang corridors,terraces(yardang ter-race and foothill denudation terrace),and dune windward slopes.The regularity of crest surface grain size char-acteristic parameters can be observed.The larger the mean grain size,the greater the degree of separation,the more symmetrical the grain size frequency distribution curve,and the broader and flatter the peaks.In contrast to the previous understanding that the ripple crests were the coarsest and the ripple troughs the finest,the present study indicates that this is not the case.Our findings indicate that the surface grain size reaches its coarsest at the windward slope in close proximity to the crest position,and its finest at the leeward slope in close proximity to the trough position.Furthermore,the grain size characteristics of similar laminae in the mixed layer of the profile is found to be similar,and exhibit a trend whereby the grain size becomes finer with the deepening of the laminae.

关 键 词：颗粒波纹 粒度 双峰分布 剖面层理 

分 类 号：P931.3[天文地球—自然地理学]