Cretaceous diatom assemblage from northern Hokkaido as the oldest fossil reccord in Japan

2016 Fiscal Year Final Research Report

• Project/Area Number: 26400497
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Stratigraphy/Paleontology
• Research Institution: Akita University
• Principal Investigator: Yamasaki Chieko (嶋田智恵子) 秋田大学, 国際資源学研究科, 研究員 (60597186)
• Co-Investigator(Renkei-kenkyūsha): SAITO Megumi (KATO Megumi) 国立科学博物館, 地学研究部, 研究主幹 (40455423) ; YAMASAKI Makoto 秋田大学, 大学院国際資源学研究科, 准教授 (40344650) ; TANAKA Yuichiro 産業技術総合研究所, 地質情報研究部, 研究部門長 (50357456)
• Research Collaborator: HIKIDA Yoshinori 中川町自然誌博物館, 学芸員
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 珪藻 / 化石 / 白亜紀 / 古第三紀 / 進化 / 適応放散

Outline of Final Research Achievements

The diatoms are one of the most important primary producers in the today’s hydrosphere on the earth. Since the Mesozoic (in effect Cretaceous) diatoms are poorly-preserved (pyritized) and/or dated in lower resolution for a progressive diagenesis, thier fossil records are very few, and are distributed with a bias of geography and stratigraphy. We discovered the fossil record of the well-preserved diatoms from the Upper Cretaceous (latest Santonian-earliest Campanian) deposit in northern Hokkaido, Japan. Afterwards, we newly discovered assemblages from the Cenomanian-Turonian, late Paleocene and Oligocene depostis, respectively. In particular, the Cenomanian-Turonian assemblages are in effect the very unique fossil record in the world. These fossil records are promisingly to contribute to an better comprehension of the adaptation and radiation during the early evolutionary stage of the old diatoms.

Free Research Field

微古生物学