Station 163 - Koyagi Fm, Takashima (Eocene of Japan)

Where: Japan (33.0° N, 129.5° E: paleocoordinates 38.4° N, 123.3° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Koyagi Formation, Middle Eocene (48.6 - 37.2 Ma)

• STRATIGRAPHIC RELATIONS: From Koyagi Fm, which unconformably overlies Mesozoic metamorphic rocks and underlies the Futagojima Fm. THICKNESS: From bed in upper 110 m of formation, which attains a total thickness of nearly 1000 m. AGE: Middle Eocene, based on molluscan biostratigraphy. STRATIGRAPHIC POSITION: From bed near top of formation.

• bed-level stratigraphic resolution

Environment/lithology: estuary or bay; lithified, coarse-grained sandstone

• ENVIRONMENT: Marginal marine, siliciclastic environment..
• SPECIFIC LITHOLOGY: Coarse sandstone. LITHIFICATION: Presumed lithified on the basis of age.

Size class: macrofossils

Collection methods: surface (float),

• COLLECTOR: A. Mizuno (c. 1964). REPOSITORY: Not stated in text, unknown.

Primary reference: A. Mizuno. 1964. Paleogene and Early Neogene molluscan faunae in West Japan. Geological Survey of Japan Report 204 [A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 70962: authorized by Austin Hendy, entered by Austin Hendy on 12.04.2007

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Exhaustive for gastropoda and bivalvia. NOMENCLATURE: Farly modern nomenclature, and species-level assignments.
Bivalvia
 Ostreida - Gryphaeidae
Pycnodonte cassis oyster
COMMENTS: Spelt Pycnodonta
 Pectinida - Anomiidae
Anomia sp. Linnaeus 1758 jingle
Gastropoda
 Neogastropoda - Turridae
 Sorbeoconcha - Naticidae
Lunatia ? utoensis Nagao 1928 moon snail
 Cerithioidea - Turritellidae
Colpospira okadai turret shell
 Cerithioidea - Pachychilidae
Faunus sp. Montfort 1810 snail
 Cerithioidea - Potamididae
Vicarya sp. d'Archiac and Haime 1854 horn snail
 Cerithioidea - Cerithiidae
? Bellatara sp. Strand 1928 cerith snail