Foraminiferal fauna and limestone lithology of the Upper Permian, and paleogeographic and tectonic implications

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The purpose of this study is to discuss collectively the Late Permian paleobiogeography of foraminifers and tectonic implications including the origin, drift, and emplacement of the geologic unit with limestone blocks, based on the examination of limestone lithology and phylogeny, time-space distribution, characteristic taxa and faunal composition of Late Permian foraminifers among areas as well as terranes A serial field survey has been performed in many limestones and many limestone thin sections have been prepared to carry out this research project. Although most of results obtained in the term of this, research project have not been published, some important results have been accumulated available for further study.Limestone lithology and foraminiferal fauna of limestone blocks and clasts were examined in detail in the Tsunemori Formation (Upper Permian accretionary complex in the Akiyoshi Terrane) and unconformably overlying Hirabaru Formation of the Upper Triassic Mine Group. The … More y show that the "Takiguchi Limestone" or the "Takiguchi Formation" formerly thought to be the basal conglomerate of the Hirabaru Formation is more reasonably included into the Tsunemori Group separating from the Mine Group.The results of foraminiferal biostratigraphy and faunas of the Upper Permian Mitai Group in the Takachiho area reveal that the upper part of the formation is assignable to the Changhsingian and not to the Wuchiapingian as previously thought. The Wuchiapingian age assignment is also applicable to the top of the Akasaka Limestone.From the field observation and foraminiferal faunal analysis between exotic blocks of the limestone conglomerate with Lepidolina and he limestone having Colaniella-Nanlingella in the Maizuru Terrane of the Kyoto Prefecture, the Maizuru Group is proved to be a deeper slope deposit without showing any stratigraphic relation as considered by Kobayashi (2003). Three papers of foraminiferal faunas of the Maizuru Group in the Hyogo Prefecture were published on the basis of the data previously accumulated and newly obtained.Concerning the FUMIO KOBAYASHI COLLECTION consisting of Paleozoic and Mesozoic limestone thin sections with foraminifers kept in the Museum of Nature and Human Activities of Hyogo, the type specimens of the collection have compiled as a database with basic information such as registered number, species, type, taxonomy, rock unit, age, locality, reference, and photomicrograph. Less