Atsunai Fm - AN-20: Middle Miocene, Japan
List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
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Bivalvia
- Cardiida
- Tellinidae
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Gastropoda
- Turritellidae
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Turritella sp.
Lamarck 1799
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| see common names | |||||||
Geography
| Country: | Japan |
| Coordinates: | 42.9° North, 143.8° East (view map) |
| Paleocoordinates: | 42.9° North, 141.0° East (Wright 2013) |
| Basis of coordinate: | estimated from map |
| Geographic resolution: | outcrop |
Time
| Period: | Neogene | Epoch: | Miocene |
| 10 m.y. bin: | Cenozoic 5 | ||
| Key time interval: | Middle Miocene | ||
| Age range of interval: | 15.98 - 11.63 m.y. ago |
Stratigraphy
| Formation: | Atsunai | ||||
| Stratigraphic resolution: | bed | ||||
| Stratigraphy comments: STRATIGRAPHIC RELATIONS: From Atsunai Fm, which overlies the Tokomuro Fm (Early Miocene) of the Atsunai Gp, and is overlain by the Shiranuka Fm (Late Miocene-Pliocene). THICKNESS: From bed with formation that attains a thickness of 700 m. AGE: Middle Miocene on the basis of molluscan biostratigraphy; Kawabata stage. STRATIGRAPHIC POSITION: From unknown position within the Atsunai Fm. | |||||
Lithology and environment
| Primary lithology: | tuffaceous,gray lithified sandy siltstone |
| Includes fossils? | Y |
| Lithology description: SPECIFIC LITHOLOGY: Gray, tuffaceous, sandy siltstone. LITHIFICATION: Lithified, on the basis of facies description. | |
| Environment: | transition zone/lower shoreface |
| Geology comments: ENVIRONMENT: Assemblage appears to be derived from an shallow shelf siliciclastic environment. TEMPERATURE: Mollusca suggest temperate water conditions. | |
Taphonomy
| Modes of preservation: | body |
| Size of fossils: | macrofossils |
Collection methods and comments
| Collection methods: | field collection |
| Reason for describing collection: | biostratigraphic analysis |
| Collection method comments: COLLECTOR: Y. Honda. REPOSITORY: Institute of Geology and Paleontology, Tohoku University, Sendai, Japan (IGPS). | |
| Taxonomic list comments:COVERAGE: Exhaustive for gastropoda and bivalvia. NOMENCLATURE: Authoritative publication with subgeneric and species-level assignments. | |
Metadata
| Database number: | 70404 | ||
| Authorizer: | A. Hendy | Enterer: | A. Hendy | Research group: | marine invertebrate |
| Created: | 2007-03-21 22:02:49 | Last modified: | 2025-02-22 15:12:02 |
| Access level: | authorizer only | Released: | 2007-03-21 22:02:48 |
| Creative Commons license: | CC0 |
Reference information
Primary reference:
| 23610. | Y. Honda. 1988. Molluscan fossils from the Atsunai Group, Kushiro Coal Field, Eastern Hokkaido, Northern Japan. Sato Ho-on Kai Special Publication (Profesoor T. Kotaka Commemorartive Volume) 351-363 [A. Hendy/A. Hendy] |