| Research Abstract |
Fossil floras from the late Cenozoic lacustrine and inner bay sediments in Kyushu were recognized as Nakayama (late Miocene), Hirakuni and Kuroki (early Pliocene), Shigehira and Otagawa (early Pliocene), Nagano, Daiwa, Hitoyoshi, Tsunematsu and Amari (late Pliocene), Yamanokuchi, Aira, Hosenji (early Pleistocene), Yoshida, Tsuetate and Oyama (early to middle Pleistocene), Tsumori, Yoshino, Nogami and Asono (middle Pleistocene), Ebino, Uchitachi, Shinkai and Aso-3/-4 sediments (middle to late Pleistocene), Iino-Kakuto (late Pleistocene), Shimabarakaiwan and Uchinomaki (late Pleistocene to Holocene) and Ariake clay (Holocene). The compositions of the fossil floras suggest that the climate changed several times from cool temperate to warm temperate conditions and the vegetations were coniferous, mixed broad-leaved and coniferous, deciduous broad-leaved, and evergreen and deciduous broad-leaved forests. It is assumed that the annual temperature based on the percentages of trees with entire-margined leaves (Wolfe, 1978) and warm elements (Hase, 1988) oscillated between about 5^ﾟ and 20 ^ﾟ during late Miocene to Holocene in Kyushu.
The Toriyamahama Formation deposited under the condition of transgression in late Pleistocene in the east coast of Kyushu. The four molluscan assemblages were recognized as Corbicula, Crassostrea-Cerithidea, Protothaca, and Haustator-Dosinia in the area.
The biostratigraphy of the Miyazaki Group in late Pliocene was clarified by the analysis of planktonic foraminiferan from the formations distributed in the northern part of Miyazaki Plain.
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