【摘要】 东海沉积中有孔虫、介形虫定量研究的结果表明:河口、陆架内部、中部、外部、陆坡与海槽,分別具有不同的有孔虫、介形虫组合,它们受水深,水温与盐度等因素控制。更多还原

【Abstract】 Foraminifera and ostracods were identified from more then 400 bottom samples taken from the East China Sea. As shown by the results of the qualitative and quantitative micropaleontological analyses, the basic factor controlling the distribution of the foraminiferal and ostracod assemblages is water depth and offshore distance, although water temperature, currents and salinity have strong influence on their distribution. These general distribution patterns have been complicated by occurences of Late Pleistocene relict fauna. Six benthic foraminiferal assemblages, each representative of increasing water depth and salinity, were recognized from estuaries to Ryukyu trench: 1. Ammonia convexidorsa-Epistominella naraensis assemblage-estuaries: 2. Ammonia beccarii var.-Elphidium advenum assemblage-water depth<55m.; 3. Bolivina cochei-Ammonia compressiuscula assemblage-50-100m.; 4. Textularia pseudocarinata-Cibicides margaritifera assemblage-100-150m.; 5. Cassidulima spp. assemblage-150-700m.; 6. Lagena spp. assemblage-700-2000m.; Accordingly, G ostracod assemblages may be distinguished as follows: 1. Albileberis sinensis assemblage-estuaries; 2. Leguminocytkereis hodgii assemblage;-<50m.; 3. Munseyella-Cytheropteron assemblage-50100m.; 4. Bairdia-Cytherelloidea assemblage-100-150m.; 5. Krithe producta assemblage-150-2000m.. There are two groups of planktonic foraminiferal species occuring in the East China Sea bottom sediments: eurythermal species such as Globigerina bulloides, Globigerina iuiniueloba and G. pumilio, and warm water species such as Orbulina universa, Globoroialia menardii. The warm water planktonic foraminifera are absent in region with water depth less than 50m., but are partly present in 50-100m. depth region and abundant beyond the 100m. isobath, thus indicating the infuence of the Kuroshio warm water current. The test size of planktonic foraminifera, the ratio of planktonic specimens to total foraminiferal mumber, as well as the ratio of ostracod to foraminiferal number increase generally with distances from coastline to trench.更多还原