Abstract

A palynological assemblage, which was identified during micropaleontological study of the oldest Cenozoic sedimentary cover of the Sea of Japan found at the Yamato Rise, allowed the substantiation of the late Paleocene (59.2–56.0 Ma) age of host deposits. The findings of only marine microfossils in these deposits, the high values of paleosalinity indicators (B, B/Ga), the chemical composition of authigenic minerals, as well as the presence of organic aggregates similar to marine algae, prove a marine genesis of these deposits. It is suggested that sedimentation occurred at the periphery of an epicontinental shallow marine basin under a subtropical climate.

中文翻译：

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大和隆起（日本海）古新世沉积物及其形成条件

摘要

在大和隆起发现的日本海最古老的新生代沉积盖层的微观古生物学研究中发现了孢粉组合，可以证实晚古新世（59.2-56.0 Ma）宿主沉积物的年龄。在这些沉积物中仅发现海洋微化石、古盐度指标（B、B/Ga）的高值、自生矿物的化学成分以及类似于海藻的有机聚集体的存在，证明了这些沉积物的海洋成因存款。推测沉积发生在亚热带气候条件下的陆缘浅海盆地外围。