Akaisi, Natori-gun (Miocene of Japan)

Where: Japan (38.2° N, 140.8° E: paleocoordinates 41.2° N, 138.1° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Moniwa Formation, Langhian (16.0 - 13.8 Ma)

• From the Moniwa beds in the broad sense (Akaisi beds are impure limestone that occupies the lower part). Moniwa Formation ranges from 16-15 Ma, according to Ogasawara (1994).

• group of beds-level stratigraphic resolution

Environment/lithology: shoreface; poorly lithified, pebbly, shelly/skeletal sandstone

• Interpreted as tidal zone to shallow marine, gravelly and rocky bottom by Sato (1991)
• Described as "impure limestone" by Hatai but the Coptothyris assemblages are in pebbly-granule coarse sandstones, partly with impure limestone, according to Sato (1991). It is likely that the impure limestone are more shell-rich intervals of the sandstone.

Size class: macrofossils

Primary reference: K. M. Hatai. 1940. The Cenozoic Brachiopoda of Japan. Science Reports, Tohoku Imperial University, Series 2 20:1-413 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 190765: authorized by Matthew Clapham, entered by Matthew Clapham on 17.12.2017

Creative Commons license: CC BY (attribution)

Taxonomic list

 Terebratulida - Terebrataliidae
Coptothyris grayi Davidson 1852