Zircon U-Pb ages of the Futomiyama Group in Toyama Prefecture, central Japan

• Kaneko Kazuo

  Tateyama Kurobe Geopark Society

• Nagata Mitsuhiro

  Graduate School of Science and Engineering, University of Toyama

• Kouchi Yoshikazu

  Graduate School of Science and Engineering, University of Toyama

• Yamamoto Koshi

  Graduate School of Environmental Studies, Nagoya University

• Otoh Shigeru

  Academic Assembly, Faculty of Sutainable Design, University of Toyama

Bibliographic Information

Other Title

• 富山県に分布する太美山層群のジルコンU-Pb年代
• トヤマケン ニ ブンプ スル タイビサンソウグン ノ ジルコン U-Pb ネンダイ

Abstract

The Futomiyama Group is mainly distributed in the southwestern (type locality area) and northeastern (Uozu area) parts of Toyama Prefecture, central Japan, and contains acid volcanic rocks. Despite intensive study, there are no zircon U-Pb ages for the acid volcanic rocks. Here we present the results of laser ablation-inductively coupled plasma-mass spectrometry zircon U-Pb analyses of four acid rocks from the Futomiyama Group in the type locality and Uozu areas. The ²³⁸U-²⁰⁶Pb weighted-mean ages are as follows: 70.2±0.7 Ma for tuff and 66.7±0.9 Ma for intrusive rocks in the type locality area; and 70.0±0.5 Ma for welded tuff and 70.6±1.1 Ma for tuff in the Uozu area. Although the Futomiyama Group was thought to be Paleogene in age, our results clarify that it belongs to the uppermost Cretaceous (Maastrichtian).

Journal

• The Journal of the Geological Society of Japan

  The Journal of the Geological Society of Japan 125 (11), 781-792, 2019-11-15

  The Geological Society of Japan

Keywords

• Futomiyama Group
• Nohi Rhyolite
• Zircon U-Pb age
• Late Cretaceous
• Toyama Prefecture

Details

• CRID: 1390846609817312256
• NII Article ID: 130007817577
• NII Book ID: AN00141768
• DOI: 10.5575/geosoc.2019.0026
• ISSN: 13499963
• ISSN: 00167630
• NDL BIB ID: 030142231
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I030142231
• Web Site: https://www.jstage.jst.go.jp/article/geosoc/125/11/125_2019.0026/_pdf
• Text Lang: ja
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed