Abstract
In this paper the relationships between the total benthic foraminiferal assemblages and the sediment characters, especially those of the fine grained part of sediment, were studied by using 17 dradge samples taken from the surrounding sea area of Kamae Bay, southern part of Oita Prefecture. As for the clustering, both MORISITA'S Similarity Index (1957) and SPEARMAN'S sum of variable formula (1963) were applied to benthic foraminiferal assemblages which 17 dradge samples contained. Consequently four groups were formed. Furthermore, 17 dradge samples were divided into five groups by the topographical features of sampling points. Such two kinds of groups resulted from the fact that the bottom sediment was formed under the influences of water movements, such as bottom current and wave turbulance, judging from the characters of fine grained part of sediment. Clay content, mud content and mean grain size of sediment probably represented the water movements mentioned above and clay content was the the most significant parameter tested.
