Ashizawa Formation

Ashizawa Formation
Stratigraphic range: Coniacian PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Unit of	Futaba Group
Sub-units	Asamigawa Member, Obisagawa Member
Underlies	Kasamatsu Formation
Overlies	Early Cretaceous Granite, Permian shale and sandstone
Location
Region	northern Honshu
Country	Japan

The Ashizawa Formation is a Coniacian geologic formation in northeastern Honshu, Japan. Dinosaur remains are among the fossils that have been recovered from the formation, although none have yet been referred to a specific genus.[1] A jawbone belonging to a therian mammal has also been discovered from this unit.[2]

Palaeofauna

• Dinosauria indet.
• Squalus sp.
• Theria indet.
• Theropoda indet. ("Futabasaurus") - "tibia"[3]

See also

• List of dinosaur-bearing rock formations
  • List of stratigraphic units with indeterminate dinosaur fossils

Footnotes

1. Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607.
2. Kusuhashi, N., Suzuki, T., Terui, K., Sato, A., and Amiot, R. (2016) A Late Cretaceous mammalian dentary from the Ashizawa Formation (Futaba Group), Fukushima, northeastern Japan. Island Arc, 25: 403–409. doi: 10.1111/iar.12133.
3. Lambert, David; the Diagram Group (1990). The Dinosaur Data Book. New York: Avon Books. pp. 63–66, 250. ISBN 978-0-380-75896-8.

References

• Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp. ISBN 0-520-24209-2.