Bibai Formation, Ishikari Group: Lutetian, Japan

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Coniferales - Cupressaceae
Glyptostrobus sp. Endlicher 1847
Shikama 1953
Shikama 1953
Shikama 1953
Angiospermae - Laurales - Lauraceae
Cinnamomum sp. Schaeffer 1760
Shikama 1953
Angiospermae - Arecaceae
Shikama 1953
Angiospermae - Malpighiales - Salicaceae
Shikama 1953
Bivalvia - Mytilida - Mytilidae
Modiola sp. Lamarck 1801
Shikama 1953
Bivalvia - Ostreida - Ostreidae
Bivalvia - Venerida - Corbiculidae
Bivalvia - Unionida - Unionidae
Unio sp. Philipsson 1788
Shikama 1953
Bivalvia - Unionida - Margaritiferidae
Gastropoda - Viviparidae
Paludina sp. Férussac 1812
Shikama 1953
Osteichthyes - Testudines - Testudinidae
Shikama 1953 1 specimen
Unnumbered specimen in Institute of Geology and Mineralogy, Hokkaido University (holotype), carapace. Collected from "incline No. 19" at the Utashinai Coal Mine.
see common names

Geography
Country:Japan
Coordinates: 43.5° North, 142.0° East (view map)
Paleocoordinates:52.1° North, 134.7° East (Wright 2013)
Basis of coordinate:based on nearby landmark
Geographic resolution:local area
Time
Period: Paleogene Epoch: Eocene
Stage: Lutetian 10 m.y. bin: Cenozoic 2
Key time interval: Lutetian
Age range of interval: 48.07 - 41.03 m.y. ago
Stratigraphy
Geological group:Ishikari Formation:Bibai
Stratigraphic resolution:formation
Stratigraphy comments: STRATIGRAPHIC RELATIONS: From Bibai Fm, which overlies the Wakkanabi and underlies the Akabira Fm, all of the Ishikari Gp (Middle Eocene). THICKNESS: From unit which reaches a thickness of 100-250 m. AGE: early Middle Eocene according to Takano and Waseda (2003). Referred only to Eocene in Mizuno (1964). STRATIGRAPHIC POSITION: Composite checklist for formation from local area.
Lithology and environment
Primary lithology: lithified sandstone
Secondary lithology: lithified siltstone
Includes fossils?Y
Lithology description: SPECIFIC LITHOLOGY: Sandstone and siltstone. LITHIFICATION: Assume to be lithified on the basis of age and photgraphic plates of Takano and Osamu (2003).
Environment:marginal marine indet.
Geology comments: ENVIRONMENT: Marine and non-marine faunal assemblage.
Taphonomy
Modes of preservation:body,cast,mold/impression
Size of fossils:macrofossils
Collection methods and comments
Collection methods:field collection
Reason for describing collection:taxonomic analysis
Collection method comments: COLLECTOR: T. Mizuno (c. 1960's). REPOSITORY: Unknown, not stated in text.
Taxonomic list comments:COVERAGE: Exhaustive for bivalvia and gastropoda. NOMENCLATURE: Somewhat antiquated, but with species-level identifications.
Metadata
Database number:70902
Authorizer:A. Hendy, A. Dunhill Enterer:A. Hendy, B. Allen
Modifier:A. Hendy Research group:marine invertebrate
Created:2007-04-11 08:34:09 Last modified:2025-02-22 15:12:02
Access level:authorizer only Released:2008-04-11 08:34:09
Creative Commons license:CC0
Reference information

Primary reference:
23771. A. Mizuno. 1964. Summary of the Paleogene molluscan faunas in North Japan. Geological Survey of Japan Report 207 [A. Hendy/A. Hendy/A. Hendy]

Secondary references:

67635 T. Shikama. 1953. On a new land turtle from Palaeogene of Hokkaido. Transactions and Proceedings of the Paleontological Society of Japan 9:19-26 [A. Dunhill/B. Allen]