Geographical Distributions of Planktic Forminifera in Japan Sea Sueface Sediments

金沢大学大学院自然科学研究科東北大学Promoting Environmental Pesearch in Pan-Japan Sea Area : Young Researchers\u27 Network, Schedule: March 8-10,2006,Kanazawa Excel Hotel Tokyu, Japan, Organized by: Kanazawa University 21st-Century COE Program, Environmental Monitoring and Prediction of Long- & Short- Term Dynamics of Pan-Japan Sea Area ; IICRC(Ishikawa International Cooperation Research Centre), Sponsors : Japan Sea Research ; UNU-IAS(United Nations University Institute of Advanced Studies)+Ishikawa Prefecture Government ; City of Kanazaw

Planktic foraminiferal assemblages and stable isotope records of the southern Japan Sea during the last 27,000 years

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Japan Sea planktic foraminifera in surface sediments: Geographical distribution and relationships to surface water mass

Modern planktic foraminifera in 51 surface sediments from the Japan Sea, a marginal sea of the western North Pacific, were studied to reveal the relationships between geographical distribution and surface water masses in the Japan Sea. Twenty-four species belonging to 10 genera were identified, of which nine species, namely Neogloboquadrina incompta, Neogloboquadrina pachyderma, Globigerina quinqueloba, Globigerina bulloides, Globigerinoides ruber, Neogloboquadrina dutertrei, Pulleniatina obliquiloculata, Globigerinoides tenellus, and Globigerinita glutinata are predominant. We recognized four geographical distribution patterns of these dominant species that are related to hydrographic conditions in the Japan Sea. The transitional water formed by the mixture between the warm Tsushima Current and cold waters in the Japan Sea is optimal for N. incompta, while the distribution of N. pachyderma is matched with cold water in the northern Japan Sea. Globigerina quinqueloba and G. bulloides appear to be associated with less saline, nutrient-rich river water from the Changjiang (Yangtze River), and G. ruber, N. dutertrei, P. obliquiloculata, G. tenellus, and G. glutinata can be regarded as indicators of Tsushima Current Water. © by the Palaeontological Society of Japan