胶州湾表层沉积物粒度特征及其沉积环境

通过对胶州湾44个表层沉积物样品粒度组分进行分析，探讨了该区表层沉积物粒度特征和沉积物类型；并以沉积物组分分布和粒度特征为依据对沉积物进行聚类分析，结合其周边河流以及海底地貌分布，对其沉积环境进行了划分。结果表明，研究区沉积物类型主要有砂质粉砂、粉砂、粉砂质砂和泥；沉积物主要粒级为1.1Φ~7.1Φ，优势粒级为5Φ~7Φ，平均值为5.7Φ，粉砂的平均含量达到58.6%，砂、黏土的平均含量为23.6%和17.3%。将研究区沉积环境划为4类：湾顶及东部近岸浅水区域(I)，大沽河—洋河水下三角洲区域(Ⅱ)，湾西南部及中部深水区域(Ⅲ)和沧口砂脊周边及湾口区域(Ⅳ)。

GRAIN SIZE DISTRIBUTION OF SURFACE SEDIMENTS IN JIAOZHOU BAY AND ITS ENVIRONMENTAL SIGNIFICANCE

44 surface sediment samples were collected from the Jiaozhou Bay of Shandong Peninsula for study of grain size distribution patterns and sediment types. Upon the basis, modern sedimentary environment is classified with grain size parameters and their relation with geographic locations using the method of system cluster. The result indicates that sediment samples of the study area are characterized by sandy silt, silt, silty sand, clayey silt and mud. The mean grain size varies from 1.1Φ to 7.1Φ, with an average of 5.7Φ. The silt dominates the deposits, which reaches 58.6% in average, and the average contents of sand and clay are only 23.6% and 17.3% respectively. The research area is divided into 4 different depositional zones.Ⅰ)the zone of bay top and shallow water area near the east coast.Ⅱ)the region of Daguhe River and Yanghe River underwater delta.Ⅲ)the southwest and central regions of the bay.Ⅳ)the periphery of Cangkou sand ridge and the bay mouth.