Challenging the enigmatic co-occurrence of radiolarians of different ages

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K13899
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Stratigraphy/Paleontology
• Research Institution: Ashiya University
• Principal Investigator: Kuwahara Kiyoko 芦屋大学, 臨床教育学部, 非常勤講師 (20507131)
• Co-Investigator(Kenkyū-buntansha): 佐野 弘好 九州大学, 理学研究院, 教授 (80136423)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 層状チャート / 未固結変形 / 放散虫化石

Outline of Final Research Achievements

We found some unconsolidated deformation structures such as disruption of thin layer and jigsaw puzzle structure in the Upper Permian radiolarian chert of the Mino Terrane, Japan. Though all parts of the chert yield the index radiolarians indicating the depositional age, different colored parts of the chert contain different radiolarian assemblage. We consider that the deformation of siliceous sediments during under an unconsolidated condition possibly resulted in the contamination of different radiolarian assemblages.

Free Research Field

古生物学

Academic Significance and Societal Importance of the Research Achievements

チャート中に含まれる放散虫化石群集に再堆積とみなせる化石が含まれていることは知られているが，その産状を調べた研究は非常に少ない．本研究では，層状チャートの単層中に未固結時の変形を多数見いだし，放散虫化石群集の混合と関連づけたことで意義がある．今後，放散虫だけでなく微化石層序全般に対して大きなインパクトを与える可能性がある．