著者
Ito Tsuyoshi Kurihara Toshiyuki Hakoiwa Hiroaki Ibaraki Yousuke Matsuoka Atsushi
出版者
新潟大学理学部
雑誌
Science reports of Niigata University. (Geology) = Science reports of Niigata University. (Geology) (ISSN:13491237)
巻号頁・発行日
vol.32, pp.1-14, 2017-03

This article describes radiolarians from a radiolarite pebble within conglomerate from a float block that was collected along the banks of the Kotaki River in the Kotaki area, Itoigawa, Niigata Prefecture, central Japan. Futobari morishitai Furutani, Inaniguttidae gen. et sp. indet., and Palaeoscenidiidae gen. et sp. indet. were recognized on etched surfaces of the pebble. Pseudospongoprunum sp., Zadrappolus sp., and Rotasphaera sp. were discovered in residues obtained by chemically treating the conglomerate. This assemblage may be compared to the assemblage around the boundary between the Pseudospongoprunum tauversi to Futobari solidus-Zadrappolus tenuis assemblage zones and corresponds to the late Silurian. This report marks the first identification of Silurian radiolarians in Niigata Prefecture, which also makes them the oldest recorded fossils from the prefecture. The clasts are also the oldest recorded radiolarian-bearing clasts within conglomerates of the Japanese Islands and the Korean Peninsula.