Station 163A - Koyagi Fm, Takashima: Middle Eocene, Japan

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Bivalvia - Ostreida - Gryphaeidae
R category
COMMENTS: Spelt Pycnodonta
see common names

Geography
Country:Japan
Coordinates: 33.0° North, 129.5° East (view map)
Paleocoordinates:38.7° North, 125.5° East (Wright 2013)
Basis of coordinate:based on nearby landmark
Geographic resolution:outcrop
Time
Period: Paleogene Epoch: Eocene
10 m.y. bin: Cenozoic 2-3
Key time interval: Middle Eocene
Age range of interval: 48.07 - 37.71 m.y. ago
Stratigraphy
Formation:Koyagi
Stratigraphic resolution:bed
Stratigraphy comments: 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.
Lithology and environment
Primary lithology:coarse lithified sandstone
Includes fossils?Y
Lithology description: SPECIFIC LITHOLOGY: Very coarse sandstone. LITHIFICATION: Presumed lithified on the basis of age.
Environment:coastal indet.
Geology comments: ENVIRONMENT: Shallow marine, siliciclastic environment..
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Collection methods and comments
Collection methods:surface (float),field collection
Reason for describing collection:biostratigraphic analysis
Collection method comments: COLLECTOR: A. Mizuno (c. 1964). REPOSITORY: Not stated in text, unknown.
Taxonomic list comments:COVERAGE: Exhaustive for gastropoda and bivalvia. NOMENCLATURE: Farly modern nomenclature, and species-level assignments.
Metadata
Database number:70963
Authorizer:A. Hendy Enterer:A. Hendy
Modifier:A. Hendy Research group:marine invertebrate
Created:2007-04-12 19:27:50 Last modified:2025-02-22 15:12:02
Access level:authorizer only Released:2008-04-12 19:27:50
Creative Commons license:CC0
Reference information

Primary reference:

23772. A. Mizuno. 1964. Paleogene and Early Neogene molluscan faunae in West Japan. Geological Survey of Japan Report 204 [A. Hendy/A. Hendy]