根田茂帯・北部北上帯境界で見出された古生代後期の含ざくろ石低温高圧型結晶片岩とその帰属

• 内野 隆之

  産業技術総合研究所地質調査総合センター地質情報研究部門

• 坂野 靖行

  産業技術総合研究所地質調査総合センター地質情報研究部門

書誌事項

タイトル別名

• Tectonic property of late Paleozoic garnet-bearing high-<i>P</i>/<i>T</i> schist at the boundary between the Nedamo and North Kitakami belts, NE Japan

抄録

An exotic block of garnet-bearing schist has been found at the boundary between the Early Triassic Takinosawa Unit of the Nedamo Belt and the Early Jurassic Nakatsugawa Complex of the North Kitakami Belt, NE Japan. This is only the second discovery of exotic schists in the Nedamo Belt; the previously identified schists occur at the boundary between the Takinosawa and early Carboniferous Tsunatori units of the Nedamo Belt. The garnet-bearing schist is characterized by a mineral assemblage of garnet + phengite + epidote + albite + quartz + titanite. Phengite with Si of 6.51-6.66 atoms per formula unit (O = 22) and the mineral assemblage suggest that the schist underwent high-P/T metamorphism prior to emplacement into its current position. The schist yields a phengite K-Ar age of ca. 290 Ma (late Paleozoic), suggesting a correlation with high-P/T schist of the Yamagami Metamorphic Rocks from the Motai-Matsugadaira Belt. This finding supports the extension of late Paleozoic high-P/T metamorphic rocks (i.e., the Renge Belt of SW Japan) to NE Japan.

収録刊行物

• 地質学雑誌

  地質学雑誌 128 (1), 1-6, 2022-02-01

  一般社団法人 日本地質学会

キーワード

• garnet-bearing schist
• high-<i>P</i>/<i>T</i> metamorphism
• phengite K-Ar age
• late Paleozoic
• Nedamo Belt
• North Kitakami Belt
• NE Japan

詳細情報

• CRID: 1390009454815684736
• NII論文ID: 130008149725
• DOI: 10.5575/geosoc.2021.0034
• ISSN: 13499963
• ISSN: 00167630
• Web Site: https://www.jstage.jst.go.jp/article/geosoc/128/1/128_2021.0034/_pdf
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• 抄録ライセンスフラグ: 使用不可