Also known as TKRS 6

Where: Okinawa, Japan (26.4° N, 128.0° E: paleocoordinates 27.0° N, 126.9° E)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Yonabaru Clay Member (Shimajiri Formation), Late/Upper Miocene (11.6 - 5.3 Ma)

• Blue-gray silty clay underlying tuffaceous beds. The Yonabaru Clay includes all Shimajiri Formation exposed below the upper tuffaceous pumiceous zone. The Yonabaru consists of bluish to gray silty to sandy clay, commonly with hackly to conchoidal fracture and fine dark-colored laminated to massive sand, weathering brown to gray, and in places contains large lime indurated concretions of sand. Most macrofossils are found in sandy beds intercalated with the clays. The Yonabaru passes under the cover of the basal gravels of the Naha limestone, and lap onto or are faukted against Paleozoic basement rocks.

• bed-level stratigraphic resolution

Environment/lithology: deep-water; poorly lithified, gray, blue, silty claystone

Size class: macrofossils

Preservation: original aragonite

Reposited in the USNM

Collection methods: quarrying,

• Collections held in USNM and UGSG repositories.

Primary reference: F. S. MacNeil. 1960. Tertiary and Quaternary Gastropoda of Okinawa: A comparison of the late Miocene, Pliocene, and Pleistocene Gastropoda of Okinawa with related faunas of East Asia together with a resume of the geological setting of the fossiliferous deposits. United States Geological Survey Professional Paper 339:1-148 [A. Miller/C. Ferguson/P. Wagner]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 42171: authorized by Austin Hendy, entered by Austin Hendy on 25.07.2004

Creative Commons license: CC BY (attribution)