Stratigraphic correlation between the Plio-Pleistocene Yabuta and Junicho Formations using volcanic ash beds, and diatom and calcareous nannofossil biostratigrahy of lower part of the Junicho Formation in northwestern Toyama Prefecture, Central Japan.

Bibliographic Information

Other Title
  • 富山県北西部の鮮新‐更新統,薮田層と十二町層の火山灰層による対比と十二町層下部の珪藻・石灰質ナンノ化石層序
  • 富山県北西部の鮮新-更新統, 藪田層と十二町層の火山灰層による対比と十二町層下部の珪藻・石灰質ナンノ化石層序
  • トヤマケン ホクセイブ ノ センシン コウシントウ ヤブタソウ ト ジュウニチョウソウ ノ カザンバイソウ ニ ヨル タイヒ ト ジュウニチョウソウ カブ ノ ケイソウ セッカイシツ ナンノ カセキソウ ジョ

Search this article

Abstract

The Yabuta Formation consists of the early to late Pliocene marine sediments distributed along the Nadaura coast, and the Junicho Formation includes late Pliocene to early Pleistocene marine sediments near Asahiyama hill, in northwestern part of Toyama Prefecture.We examined volcanic ash beds in the Yabuta and Junicho Formations by petrographical method and measuring chemical component of volcanic glass. Two pairs of the volcanic ash beds (MT2-T1, UN-T3) can be correlated between the Yabuta and Junicho Formations, and the middle-upper part of the Yabuta Formation can be correlated to the lower part of the Junicho Formation. Fossil diatoms from the lower part of the Junicho Formation showed that the boundary between the Neodenticula koizumii-Neodenticula kamtschatica Zone and the N. koizumii Zone is around the T3 volcanic ash bed that is widely traced in the Hokuriku Region. Calcareous nannofossil biostratigraphy of the lower part of the Junicho Formation indicates that Datum A (2.75 Ma) is demarcated about 4 meter below the T3 volcanic ash bed. A widespread tephra of the Habutaki I-MT2 ash layer is situated about 14 m below the Datum A in the Junicho Formation.

Journal

Citations (12)*help

See more

References(34)*help

See more

Details 詳細情報について

Report a problem

Back to top