汕头东部海域海砂开采区快速回淤成因分析  

The Analysis of the Causes of Rapidly Back Silting in the Sea Area Eastern Shan-Tou

作　　者：马媛[1] 魏巍[1,2] 陈静[1] 杨阳[1] 肖志健[1] 张志强[1] 周普志[1] 

机构地区：[1]国家海洋局南海工程勘察中心,广东广州510300 [2]中国海洋大学环境科学与工程学院,山东青岛266100

出　　处：《中国海洋大学学报（自然科学版）》2013年第7期78-82,共5页Periodical of Ocean University of China

基　　金：国家海洋局南海分局科学技术局长基金项目(0801)资助

摘　　要：利用汕头东部海域海砂开采区浅地层剖面及地形地貌等实测资料,对比分析了采砂区开采前后的地形地貌及浅部地层的特征变化,发现采砂活动破坏采砂区原始浅部地层,形成了3个采砂坑,且采砂坑已经被淤平,最大回淤厚度达7m。采砂坑快速回淤形成的海底水深与原始海底基本一致,但回淤物质的声学反射强度减低,颗粒细化。本文使用淤泥质浅滩水域淤强公式进行正常自然条件下的回淤计算,结果表明,回淤厚度与实测值相差至少1个数量级,根据水文气象观测资料,初步分析认为热带风暴"莎莉嘉"引起的骤淤是形成采砂坑快速回淤现象的主要原因。Integrated analysis and study on sub-bottom profile, single beam echosounders,geological data of sea sand exploitation area in eastern Shantou before and after exploitation, the paper suggest that Sea Sand exploitation destroyed natural shallow stratigraphic framework and formed three sandpits. After the exploitation, the sandpits are rapidly back silted. The most thickness of sandpits reaches 7m. The geomorphologic characteristics of siltation seabed are similar to that of natural seabed. The acoustic reflection intensity of siltation material is decreased, and its particles size becomes finer. The paper presents a calcu- lation of silt thickness by using siltation formula of silt tidal flat in normal natural conditions. The calculation results are at least an order of magnitude than the measured data. According to the hydro-meteorological observational data, preliminary research results show that sudden silting caused by tropical storm ＂Sarika＂ is the main reason of rapidly back silting in sea sand exploitation area.

关 键 词：汕头东部海域 风暴骤淤 海砂开采坑 浅地层剖面 回淤计算 

分 类 号：P736[天文地球—海洋地质]