Diatom geochronology of the Miocene Arakawa Formation in the Hiki Hills, Saitama Prefecture, central Japan

Mahito Watanabe, Masaki Takahashi
2004 Journal of the Japanese Association for Petroleum Technology  
Diatom biostratigraphy was applied for the Miocene marine sequence distributed along the Arakawa River in the northern part of the Hiki Hills, central Japan. Five out of 36 collected samples (calcareous nodules) yielded age diagnostic diatom fossils. They were assigned to the lower Denticulopsis lauta Zone (NPD 4 A) between the diatom biohorizons D 41 (15.8Ma) and D 41.5 (15.6Ma). Based on the diatom geochronology, the dated section (Kuroda Section) is correlative to the middle to upper part of
more » ... the Uematsu Section, located about 2,500m northeast from the Kuroda Section. Fold and/or fault are inferred between the Kuroda and Uematsu Sections, because easterly inclined sediments of the same horizon are exposed repeatedly.
doi:10.3720/japt.69.65 fatcat:iuboefgwerghjcty66sdvzyq2q