Paleobiogeographic study of the carboniferous and permian brachiopods from the Akiyoshi Terrane
Grant-in-Aid for Scientific Research (C).
|Research Institution||KYUSHU UNIVERSITY|
柳田 寿一 九州大学, 理学, 教授
YANAGIDA Juichi Kyushu Univ., Fac.of Sci., Professor, 理学部, 教授 (70037183)
|Project Fiscal Year
1992 – 1993
Completed(Fiscal Year 1993)
|Budget Amount *help
¥2,400,000 (Direct Cost : ¥2,400,000)
Fiscal Year 1993 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1992 : ¥1,800,000 (Direct Cost : ¥1,800,000)
|Keywords||AKIYOSHI LIMESTONE GROUP / CARBONIFEROUS BRACHIOPODA / MILLERELLA YOWARENSIS ZONE / PSEUDOSTAFFELLA ANTIQUA ZONE / NAMURIAN A - C / GLOBAL COOLING / TSUNEMORI FORMATION / KARITA FORMATION / 秋吉石灰岩層群 / 石炭紀腕足類 / Millerella yowarensis帯 / Pseudostaffella antiqua帯 / Namurian A〜C / 世界的冷涼化 / 常森層腕足類 / 刈田層腕足類 / NamarianA〜C / 秋吉テレーン / 石灰紀およびベルム紀腕足類 / 古生物地理|
Following results for my study on the Carboniferous brachiopods in the Akiyoshi Terrane have been obtained.
1. The faunal elements of the Akiyoshi Limestone Carboniferous brachiopods show a remarkable change from the Millerella yowarensis Zone to the Pseudostaffella antiqua Zone. Early Carboniferous representative genera and species are almost all disappeared beneath the M.yowarensis Zone. Some remnants and the newly appeared genera which diversed in the Late Carboniferous and Early Permian characterize the M.yowarensis Zone.
2. In the Pseudostaffella antiqua Zone most elements are replaced by the newly appeared genera of which some are the representative elements of a cool water province in early Permian time.
3. The Millerella yowarensis and Pseudostaffella antiqua Zones contain some endemic genera such as Weiningia and Neoschizophoria which distribute in Asia and Japan, respectively.
4. The Millerella yowarensis and Pseudostaffella antiqua Zones are correlated withy the Namurian A (or S
erpukhovian) and Namurian C (or midle Bashkirian) of Western Europe and Russia, respectively.
5. The Carboniferous brachiopods of the Akiyoshi limestone Group all flourished in an organic reefy environment. A conspicuous change of the faunal elements between Namurian A and Namurian C, and the appearance of the local genera in these zones may be affected by the beginnig of the global decline of temperature, especially in the higher latitudinal regions.
Following results were obtained in the Permian brachiopods in the Akiyoshi Terrane.
1. The Permian brachiopods of the Tsunemori Formation which was accreted by the Akiyoshi limestone Group by the collapse of the Akiyoshi sea mount have a very important information not only for determining the age of the Tsunemori Formation but also for appreciation of the palaeobiogeographic situation based on the brachiopod fauna.
These Permian brachiopods are now under preparation for study. The Upper Permian brachiopods from the Karita Formation, Hiroshima which may be correlative with the Tsunemori Formation have been described and discussed by Yanagida and others. Less
Research Output (7results)