Abstract
In Oita City, there are distributed the Sekinan and the Oita groups which deposited during the late Tertiary and the early Quaternary.By pollen analysis of these deposits, the following results are obtained.1) The floral changes of that time in this region are similar to those of the Osaka group and its equivalents of the other regions in Japan, and summarized as follows.a) At the middle part of the Higashiwasada formation (the middle part of the Sekinan group), among the Tertiary floras Nyssa becomes extinct, but Metasequoia is still found in this stage.b) The first appearance of Cryptomeria in this region is shown at the middle part of the Handa formation (the upper part of the Sekinan group).c) In the upper part of the Takio formation (the lower part of the Oita group) Metasequoia has already disappeared, while Fagus becomes predominant.2) The first cooling of the climate may be indicated by the appearance of deciduous Quercus at the middle part of the Higashiwasada formation. Therefore, it is presumed that this horizon indicates the Plio-Pleistocene boundary in this region.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
