YBY-2 - Soun Mudstone Mbr, Yubetsu Fm, Akan district: Early Oligocene, Japan

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Bivalvia - Venerida - Corbiculidae
C category
see common names

Geography
Country:Japan
Coordinates: 43.3° North, 144.1° East (view map)
Paleocoordinates:45.9° North, 140.7° East (Wright 2013)
Basis of coordinate:based on nearby landmark
Geographic resolution:outcrop
Time
Period: Paleogene Epoch: Oligocene
Stage: Rupelian 10 m.y. bin: Cenozoic 4
Key time interval: Early Oligocene
Age range of interval: 33.9 - 27.3 m.y. ago
Stratigraphy
Formation:Yubetsu Member:Soun Mudstone
Stratigraphic resolution:bed
Stratigraphy comments: STRATIGRAPHIC RELATIONS: From Soun Mudstone Mbr of the Yubetsu Fm of the Urahoro Gp, which overlies the Rushin Fm and is overlain by the Shitakara Fm, both of the Urahoro Gp (Early Oligocene). THICKNESS: From bed within unit 250-500 m thick. AGE: Early Oligocene based on molluscan biostratigraphy. STRATIGRAPHIC POSITION: Unknown position within formation.
Lithology and environment
Primary lithology: lithified sandstone
Secondary lithology: lithified siltstone
Includes fossils?Y
Includes fossils?Y
Lithology description: SPECIFIC LITHOLOGY: Sandstone, siltstone, coal and conglomerate. LITHIFICATION: Assumed to be lithifed on the basis of figured specimens and age.
Environment:coastal indet.
Geology comments: ENVIRONMENT: Coastal marine, siliciclastic environment.
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Collection methods and comments
Collection methods:field collection
Reason for describing collection:taxonomic analysis
Collection method comments: COLLECTOR: Presumably Y. Honda (c. 1989). REPOSITORY: Probably Tohoku University, Japan.
Taxonomic list comments:COVERAGE: Exhaustive for gastropoda, bivalvia and scaphopoda. NOMENCLATURE: Authoritative publication, using moderately recent nomenclature, subgenus and species level designations.
Metadata
Database number:70726
Authorizer:A. Hendy Enterer:A. Hendy
Research group:marine invertebrate
Created:2007-04-03 23:20:03 Last modified:2025-02-22 15:12:02
Access level:authorizer only Released:2007-04-03 23:20:02
Creative Commons license:CC0
Reference information

Primary reference:

23698. Y. Honda. 1989. Paleogene molluscan faunas from the Kushiro Coal Field, Eastern Hokkaido. Tohoku University, Science Report, 2nd series 60(1):1-137 [A. Hendy/A. Hendy]