摘要
对渤海湾西岸39件表层沉积样中有孔虫和介形类进行了分析,共鉴定底栖有孔虫20属41种,海相介形类26属32种。底栖有孔虫分布主要受离岸距离、河流入海、潮流与相应的水深、盐度和沉积速率影响,可划分3个有孔虫组合区。南部组合Ⅰ区以阿卡尼圆形五玦虫和毕克卷转虫变种为主,代表了受淡水注入影响的近岸带河口沉积环境;西北部组合Ⅱ区为毕克卷转虫变种—具瘤先希望虫—阿卡尼圆形五玦虫组合,代表了近岸浅水沉积环境;组合Ⅲ区中优势种为具瘤先希望虫,主要位于10m以深水域,沉积环境更近似于正常海相环境。海相介形类分布主要受盐度、水深和沉积物的底质类型与运移规律影响,并大致以10m等深线为界划分为2个介形类组合区。浅部组合Ⅰ以陈氏新单角介为绝对优势种,代表了广温、广盐的滨岸浅海河口环境;组合Ⅱ以美山双角花介为绝对优势种,生存环境少受淡水影响,离岸相对较远。
39 surface sediment samples taken from the western coast of Bohai Gulf are analyzed by the authors for foraminifera and ostracoda.A total of 41 benthic foraminifera species of 20 genera and 32 marine ostracoda species of 26 genera,were recognized.The distribution of benthic foraminifera is mainly depending upon the distance to the coast,freshwater injection,tidal current and corresponding water depth,salinity and sedimentation rate.There are three foraminifera assemblages.The southern part of the water is dominated by AssemblageⅠ with Quinqueloculina akneriana rotundaand Ammonia beccarii vars.as leading species,representing an estuarine depositional environment under the affect of fresh water injection.The Assemblage Ⅱis mainly observed in the northwest dominated by Ammonia beccarii vars.,Protelphidium tuberculatumand Quinqueloculina akneriana rotunda,representing a coastal shallow water depositional environment.The Assemblage Ⅲ dominated by Protelphidium tuberculatum,however,mainly occur in the water deeper than 10 m,more or less similar to the normal marine environment.The distribution of marine ostracoda species are mainly affected by salinity,water depth,the bottom sediment types and migration law.There are two assemblages approximately separated by the 10 misobath.The shallow Assemblage Ⅰ is absolutely dominated by the species of Neomonoceratina chenae,representing the coastal and shallow estuarine environment with wide temperature and salinity,while the AssemblageⅡ,which is dominated by Bicornucythere bisanensis,indicates an offshore environment less affected by fresh water.
作者
李稳
宫少军
赵卫
LI Wen;GONG Shaojun;ZHAO Wei(Marine Geological Survey Center of Tianiin,Tianiin 300170,China;Key Laboratory of Carrying Capacity Assessment for Resource and Environment,Ministry of Natural Resources,Beijing 100083,China)
出处
《海洋地质前沿》
CSCD
2018年第9期32-42,共11页
Marine Geology Frontiers
基金
天津华北地质勘查局C类科研项目"典型海岸带资源环境承载能力评价技术方法研究"(HK2017-C9)
自然资源部资源环境承载力评价重点实验室开放课题资助课题(CCA2017.04)
关键词
渤海湾西岸
有孔虫
介形类
表层沉积物
western coast of Bohai Gulf
foraminifera
ostracoda
surface sediments
