Japan Geoscience Union Meeting 2016

Presentation information


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

[M-IS13] Evolution of the Pelagic Realm

Mon. May 23, 2016 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall HALL6)

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, Graduate School of Science and Technology, Kumamoto University), Katsunori Kimoto(Japan Agency for Marine-Earth Science and Technology), Tatsuo Nozaki(Research and Development Center for Submarine Resources, Japan Agency for Marine-Earth Science and Technology), Hayato Ueda(Department of Geology, Niigata 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)

5:15 PM - 6:30 PM

[MIS13-P01] A search for impact ejecta deposits in the Upper Triassic limestone of the Pizzo Mondello section, western Sicily, Italy.

*Tatuya Kuranari1, Katsuhito Soda1, Daisuke Yamashita1, Tetsuji Onoue1 (1.Department of Earth and Environmental Sciences, Graduate School of Science and Technology, Kumamoto University)

Keywords:Late Triassic, ejecta sediment, Pizzo Mondello, limestone, main trace element analysis

The 34-million-year (My) interval of the Late Triassic is marked by the formation of several large impact structures on Earth, including the 90-km-diameter Manicouagan impact crater In Quebec, Canada. This crater occurred in the middle–upper Norian (ca. 215.5 Mya). Late Triassic impact events have been considered a factor in biotic extinction events in the Late Triassic (e.g., end-Triassic extinction event), but this scenario remains controversial because of a lack of stratigraphic records of ejecta deposits. The Manicouagan impact ejecta deposits are known only from Mino terrane, Central Japan and southwestern Britain. To investigate the impact ejecta deposit derived from the Manicouagan impact crater, we examined the stratigraphic variations in major and trace element concentrations from the Upper Triassic Pizzo Mondello section in western Sicily, Italy. The Pizzo Mondello consists of a continuously exposed sequence (a 450m thick) of upper Carnian through late Norian (Upper Triassic) pelagic limestone. The trace element data from this study show a consistent trend of decreasing Cr and Ni values starting in the lower Norian. Concentration of these elements are observed in the upper part of the Pizzo Mondello section and is roughly located at the base of the Epigondolella bidentata conodont zone in the late Norian.