870. AN EARLY CRETACEOUS (EARLY MIDDLE ALBIAN) PLANKTONIC FORAMINIFERAL FAUNA FROM THE HINAGU FORMATION OF NORTHERN KYUSHU, JAPAN

DOI Web Site

Bibliographic Information

Other Title
  • 870. 北部九州日奈久層より産する前期白亜紀(中期アルビアン)浮遊性有孔虫化石
  • 北部九州日奈久層より産する前期白亜紀(中期アルビアン)浮遊性有孔虫化石〔英文〕
  • ホクブ キュウシュウヒ ナクソウ ヨリ サンスル ゼンキ ハクアキ チュ

Search this article

Description

A fairly well-preserved planktonic foraminiferal assemblage was recovered from the Hinagu Formation when recovery of radiolarian was attempted from a siliceous mudstone by applying the hydrofluoric acid extracting method. The assemblage comprises Globigerinelloides barri (Bolli, Loeblich and Tappan), Hedbergella delrioensis (Carsey), H. planispira (Tappan), H. trocoidea (Gandolfi), and Ticinella primula Luterbacher. The joint occurrence of the Albian species of T. primula and G. barri which had been known only from the late Aptian is used to establish an early middle Albian age of the fauna. An ammonite assemblage consisting of two species had previously been used to assign an early Aptian age to the lower half of the Hinagu Formation. This ammonite age contradicts ages indicated by both planktonic foraminifera and radiolarians. The Yatsushiro Formation which is considered to unconformably overlie the Hinagu Formation also had been dated by ammonites as late early Albian. Microfossil ages are not yet available for this formation. If the ammonite age is unequivocal for this formation, those ammonite-bearing lithofacies labeled as the Yatsushiro Formation are likely to be a coeval but shallower water facies of the Hinagu Formation.

Journal

Keywords

Details 詳細情報について

Report a problem

Back to top