湛江湾海域表层沉积物粒度特征及沉积环境  

Grain-size characteristics of surface sediment and sedimentary environment in Zhanjiang Bay

作　　者：郝连成 远继东 郑立龙 张健康 张德程 代友旭 HAO Liancheng;YUAN Jidong;ZHENG Lilong;ZHANG Jiankang;ZHANG Decheng;DAI Youxu(Yantai Center of Coastal Zone Geological Survey,China Geological Survey,Yantai 264004,China;School of Ocean Sciences,China University of Geosciences,Beijing 100083,China)

机构地区：[1]中国地质调查局烟台海岸带地质调查中心,烟台264004 [2]中国地质大学(北京)海洋学院,北京100083

出　　处：《海洋地质前沿》2022年第8期1-10,共10页Marine Geology Frontiers

基　　金：中国地质调查局项目“雷州半岛东部海岸带综合地质调查”(DD20208011)。

摘　　要：根据湛江湾海域2020年10月采集的61个表层沉积物样品粒度分析结果,对沉积物粒度参数进行了总结,划分了沉积物类型,结合Pejrup三角图解对湛江湾海域沉积动力环境进行了分区,运用Gao-Collins粒径趋势分析模型,探讨了沉积物运移趋势。结果表明,湛江湾海域表层沉积物类型共有5种,其中砂、粉砂质砂、砂质粉砂分布最广,粒度组成以细砂为主,平均粒径均值为3.93Φ,分选较差,粒度分布曲线以正偏、正态分布为主。沉积动力判别图解揭示湛江湾海域沉积水动力较强,整体表现为湾内比湾外弱、湾外向外海方向逐渐减弱的特征。粒径趋势分析反映出湛江湾内整体向南部潮流深槽方向运移,湾外围绕沉积中心整体呈逆时针方向运移。湛江湾海域表层沉积物的运移和分布主要受泥沙来源及潮流、波浪、沿岸流等沉积动力环境的共同作用,近年来,人类活动的影响愈加明显。Based on the results of particle size analysis of 61 surface sediment samples collected in October,2020 in Zhanjiang Bay,Guangdong,China,the particle size parameters of sediments were summarized,and the sedi-ment types were classified.The Pejrup triangle diagram was used to divide the sedimentary dynamic environment of Zhanjiang Bay.The Gao-Collins particle size trend analysis model was used to explore the sediment migration trend.Results show that there are five types of surface sediments in Zhanjiang Bay,among which sand,silty sand,and sandy silt are the most widely distributed.The particle size composition is mainly fine sand,and the average particle size is 3.93Φ.The sorting is poor.The particle size distribution curve is mainly positive and normal distri-bution.The discriminant diagram of sedimentary dynamics reveals that the sedimentary hydrodynamic force in Zhanjiang Bay is strong;and it is generally weaker inside the bay than outside the bay and gradually weakens oceanward.The particle size trend analysis shows that the whole water in Zhanjiang Bay moves to the tidal deep trough in the south,while water of outer bay flows counterclockwise around the sedimentary center.The move-ment and distribution of surface sediments in the bay are mainly affected by sediment sources and sedimentary dy-namic environments such as tides,waves,and coastal current.In recent years,the influence of human activities has become more obvious.

关 键 词：表层沉积物 粒度参数 运移趋势 沉积动力环境 湛江湾 

分 类 号：P736.21[天文地球—海洋地质]