USGS 17519, 37th Division General Hospital (WF 47) (Pleistocene to of Japan)

Where: Okinawa, Japan (26.3° N, 127.8° E: paleocoordinates 26.4° N, 127.7° E)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Naha Formation (Ryukyu Group), Calabrian to Calabrian (1.8 - 0.1 Ma)

• The lower part of the Riukiu Limestone is called the Naha Limestone. Naha Formation ranges from the middle Calabrian (c. 1.3 Ma) to the Middle Pleistocene (c. 0.4 Ma), according to Yamamoto et al. (2006).

• group of beds-level stratigraphic resolution

Environment/lithology: lagoonal or restricted shallow subtidal; poorly lithified, brown, white, calcareous grainstone and poorly lithified, brown, white limestone

• Probably is a reef limestone, but only coral rich in a few places. It is presumed that the Naha Limestone is a detrital lagoon deposit or a reef detritus deposited on an insular shelf. The lower part is more widespread that the upper part, probably reflecting erosion during deposition of the Yontan Limestone. The highest beds are less conglomeratic and generally contain abundant algal nodules.
• Poorly indurated medium to coarse grained lime sand, but other parts of it range from a powdery limestone to a dense nonporous limestone. It ranges in color from nearly white to brownish yellow.

Size class: macrofossils

Collected by Warren Fuller; reposited in the USNM

Primary reference: G. A. Cooper. 1957. Tertiary and Pleistocene Brachiopods of Okinawa, Ryukyu Islands. United States Geological Survey Professional Paper 314(A):1-20 [A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 190222: authorized by Matthew Clapham, entered by Matthew Clapham on 03.12.2017

Creative Commons license: CC BY (attribution)

Taxonomic list

Rhynchonellata
 Terebratulida - Frenulinidae
Jolonica ryukyuensis Yabe and Hatai 1935
 Terebratulida - Terebratulidae
Gryphus hanzawai Yabe and Hatai 1935
 Terebratulida - Cancellothyrididae
 Rhynchonellida - Basiliolidae