Japan Geoscience Union Meeting 2014

Presentation information

Oral

Symbol M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS25_28AM1] Evolution of the Pelagic Realm

Mon. Apr 28, 2014 9:15 AM - 10:45 AM 411 (4F)

Convener:*Atsushi Matsuoka(Department of Geology, Faculty of Science, Niigata University), Toshiyuki Kurihara(Graduate School of Science and Technology, Niigata University), Yasuhiro Kato(Department of Systems Innovation, Graduate School of Engineering, University of Tokyo), Tetsuji Onoue(Earth and Environmental Sciences, Faculty of Science, Kagoshima University), Katsunori Kimoto(Japan Agency for Marine-Earth Science and Technology), Tatsuo Nozaki(Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology), Hayato Ueda(Faculty of Education, Hirosaki University), Kenta Kobayashi(Department of Geology, Faculty of Science, Niigata University), Takashi Hasegawa(Division of Global Environmental Science and Engineering, Graduate School of Natural Science and Technology, Kanazawa University), Chair:Toshiyuki Kurihara(Graduate School of Science and Technology, Niigata University), Takashi Hasegawa(Division of Global Environmental Science and Engineering, Graduate School of Natural Science and Technology, Kanazawa University)

10:30 AM - 10:45 AM

[MIS25-06] Radiolarian morphology as a proxy for reconstructing pelagic environments: problem and perspective

*Atsushi MATSUOKA1 (1.Niigata University)

Keywords:radiolarians, taxonomy, species concept, morphological diversity, pelagic realm

Late Paleozoic and Mesozoic radiolarian cherts are widely distributed within accretionary complexes in the Circum-Pacific and Alps-Himalaya orogenic belts. These cherts are materials for reconstructing the paleoenvironment of the Panthalassa and the Tethys. Many proxies have been developed to elucidate the environment of the past pelagic realm. Species diversity in radiolarian assemblages is expected to be one of proxies for monitoring paleoenvironmental change. However, the species concept of radiolarians is not always consistent throughout the Phanerozoic time. This makes a serious problem to use radiolarian diversity for elucidating environmental fluctuations. This paper documents the present status of taxonomy for Mesozoic and recent radiolarians. Detailed morphological analysis of radiolarian tests and the understanding of the morphogenesis through culture work are clues toward reconstructing pelagic environments in the past oceans.