摘要
碎屑矿物在判别沉积物来源以及沉积环境变化等方面具有重要意义。基于对2013年汛前与汛后采集的黄河尾闾河道表层沉积物样品的鉴定,探讨了调水调沙工程实施导致的水动力变化对碎屑矿物组成特征的影响。结果表明,汛前或汛后黄河尾闾河道表层沉积物中共鉴定出重矿物31种,轻矿物11种。尾闾河道沉积物整体以轻矿物为主,占比达99%以上。重矿物优势矿种共8种,分别为普通角闪石、绿帘石、褐铁矿、阳起石、水黑云母、石榴子石、榍石和碳酸盐,其中普通角闪石占比高达29.98%,是主要标志性重矿物;轻矿物优势矿种共3种,分别为石英、斜长石及钾长石,其中石英占比高达59.75%,是主要优势矿种,并可用于确定物源。比较而言,汛后8种重矿物含量之和比汛前增加3.7%,尤其是普通角闪石,其在汛后占比较汛前增加8.62%。与之不同,轻矿物含量在汛前与汛后差异不大,但沿程变化明显。研究发现,尽管调水调沙工程在改变尾闾河道水动力的同时并未使其轻矿物组分发生明显改变,但其导致的重矿物沉积分异却较为明显。
Detrital mineral has great significances in determining the sources of sediment and the variations of sedimentary environment.Based on the identification of surface sediments sampled in tail channel of the Yellow River at pre-flood season and post-flood season in 2013,this paper discussed the impacts of hydroynamic condition variations caused by the Flow-sediment Regulation Project (FSRP) on the composition of detrital mineral in sediments.Results showed that,whether at pre-flood season or at post-flood season,31 kinds of clastic heavy minerals and 11 kinds of clastic light minerals were identified in sediments of the tail channel.Light mineral was dominated in sediments and its contents at pre-flood season and post-flood season all exceeded 99%.The dominated minerals of clastic heavy minerals in sediments included 8 kinds:normal angle hornblende,epidote,limonite,actinolite,black mica,garnet,sphene and water carbonate.And among them,the percent of ordinary angle amphibole was the highest and the value reached 29.98%.The dominated minerals of clastic light minerals included 3 kinds:quartz,plagioclase and potassium feldspar.And the percent of quartz was the highest (59.75%) which could be used to determine the sources of sediments.Compared to pre-flood season,the percent of 8 kinds of clastic heavy minerals was increased by 3.7%(particularly for ordinary angle amphibole which increased by 8.62%).In contrast,no obvious variation of clastic light minerals was observed between pre-flood season and post-flood season.This study found that although the FSRP significantly altered the hydrodynamic conditions of tail channel,it produced no obvious influence on the composition of clastic light minerals.By comparison,the sedimentary differentiation of clastic heavy minerals in sediments was greatly altered by the FSRP.
作者
张党玉
孙志高
王伟
ZHANG Dang-yu;SUN Zhi-gao;WANG Wei(National Demonstration Center for Experimental Geography Education,Fujian Normal University,Fuzhou 350007,China;School of Geographical Sciences,Fujian Normal University,Fuzhou 350007,China;School of Resources and Environmental Engineering,Ludong University,Yantai 264025,China)
出处
《滨州学院学报》
2019年第2期67-73,共7页
Journal of Binzhou University
基金
国家自然科学基金资助项目(41371104,41171424)
关键词
碎屑矿物
组成特征
尾闾河道
调水调沙工程
黄河
detrital mineral
composition
tail channel
Flow-sediment Regulation Project
Yellow River
