摘要
对取自渤海湾的 307 个表层沉积物进行了元素测试和粒度分析。渤海湾表层沉积物的常微量元素呈现 4 种组合:富集于粗粒沉积区的 SiO2、Na2O 亲碎屑元素组合;富集于细粒沉积区的以 Al2O3和重金属元素为代表的亲黏土元素组合;与缺氧环境有关的 MnO、V、TOC 元素组合和与河流输入有关的陆源 CaO、TiO2元素组合。粒度粗细主导了渤海湾元素含量分布的整体格局;海域河流物源供应不同较大影响了渤海湾南部(富 Na2O、CaO 和 SiO2)和北部(富 Ba 和 P2O5)在元素含量上的差异;高流速潮流对海底的冲刷再分配导致曹妃甸南侧 Sr、Ca 元素的条带状富集异常;有机质在细粒沉积区的富集导致缺氧环境的形成和 K2O、Mn、V、自生黄铁矿的海洋自生化学沉积;人类活动导致以 Pb 为代表的重金属污染在河流入海口、港口及沿岸海域的元素分布异常;曹妃甸沙坝内侧的泻湖(海洋钙质生物沉积)与沙坝外侧水下岸坡(陆源碎屑沉积)的截然不同的物源,导致了独特地貌沉积环境下元素分布的局部差异。
The geochemistry and particle size of 307 surface sediment samples collected from the Bohai Bay were analyzed. The surface sediments in the Bohai Bay show 4 element assemblages: philo-clastic element assemblage (SiO2 and Na2O) enriched in coarse-grained deposition area, philo-clay element assemblage (Al2O3 and most of the heavy metal elements) enriched in fine-grained deposition area, redox sensitive elements assemblage (MnO, V, and TOC) associated with anoxic environment and terrestrial element assemblage (CaO and TiO2) related to river input. Particle size dominates the overall distribution pattern of the element contents in the sediment from the Bohai Bay;different river sources strongly affect the element content differences between the southern (rich in Na2O, CaO and SiO2) and the northern (rich in Ba and P2O5) parts of the Bohai Bay;the erosion and redistribution of fast flowing tidal currents to the sediments lead to a strip-like enrichment of Sr and Ca in south of Caofeidian;the enrichment of organic matter in fine-grained deposition area leads to the formation of anoxic environment and marine autogenous chemical deposition of K2O, Mn, V and authigenic pyrite;human activities cause an abnormal enrichment of heavy metal elements (represented by Pb) in river estuaries, ports and coastal waters;the distinct sources between the la- goon (marine calcareous deposition) on the inner side of the Caofeidian sand bar and the underwater bank slope (terrigenous clastic deposition) on the outside of the Caofeidian sand bar, leads to local element differences under the unique geomorphic sedimentary environment.
作者
张连杰
朱龙海
张盼
赵博
王鹏
ZHANG Lian-jie;ZHU Long-hai;ZHANG Pan;ZHAO Bo;WANG Peng(National Marine Environmental Monitoring Center, Dalian 116023, China;Ocean University of China,Qingdao 266100, China)
出处
《海洋科学》
CAS
北大核心
2019年第6期78-87,共10页
Marine Sciences
基金
国家自然科学基金项目(51809052)~~
关键词
渤海湾
元素地球化学
因子分析
自生化学沉积
缺氧环境
Bohai Bay
elemental geochemistry
factor analysis
authigenic chemical deposition
anoxic environment
