Study of flow-and depositional-models of sediment-gravity flow in verved sediment and their control factors

点击翻译按钮获取中文摘要

We studied frequency of occurrence, spatio-temporal distributions and sedimentary process of sediment-gravity flow deposits intercalated in lacustrine varve sediments and their diatom assemblage in the Pleistocene Hiruzenbara Formation, Okayama Prefecture, central Japan. As the results, sedimentological aspects of sediment-gravity flow deposits(river-flood origin and failure of paleo-lake slope origin) in the formation and their occurrence interval(about tens to hundreds years) are revealed from field researches, and the primary conditioning of study of the inverse analysis of these sediment-gravity flow deposits are established. The diatom assemblage of the varve sediments showing distinctive dominance of two species throughout the formation and periodic changes of the size of one of them are also detected.