R6317 - Obira (Saku Formation): Turonian, Japan

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Cephalopoda - Ammonitida - Tetragonitidae
Tetragonites glabrus (Jimbo 1910)
1 specimen
1 specimen
Cephalopoda - Ammonitida - Desmoceratidae
1 specimen
Damesites ainuanus Matsumoto 1957
3 specimens
Cephalopoda - Ammonitida - Scaphitidae
3 specimens
4 specimens
7 specimens
Scaphites planus (Yabe 1910)
3 specimens
3 specimens
Cephalopoda - Ammonitida - Nostoceratidae
Eubostrychoceras sp. Matsumoto 1967
3 specimens
see common names

Geography
Country:Japan
Coordinates: 44.1° North, 142.0° East (view map)
Paleocoordinates:51.4° North, 142.7° East (Wright 2013)
Basis of coordinate:estimated from map
Geographic resolution:outcrop
Time
Period: Cretaceous Epoch: Late Cretaceous
Stage: Turonian 10 m.y. bin: Cretaceous 6
Key time interval: Turonian
Age range of interval: 93.9 - 89.8 m.y. ago
Stratigraphy
Formation:Saku
Stratigraphic resolution:bed
Stratigraphy comments: STRATIGRAPHIC RELATIONS: Presumably from the Saku Formation of Turonian age, which overlies pre-Cenomaniann Cretaceous deposits. THICKNESS: Total unit has thickness of 1200 m. AGE: Turonian, based on ammonite biostratigraphy.
Lithology and environment
Primary lithology:concretionary lithified silty,sandy mudstone
Secondary lithology: lithified conglomeratic sandstone
Includes fossils?Y
Lithology description: GENERAL LITHOLOGY: Mudstone, sandy siltstone, tuffite, and intercalated sandstone and conglomerate; specimens occur in calcite concretions. LITHIFICATION: Lithified, assumed as from concretions.
Environment:coastal indet.
Geology comments: ENVIRONMENT: Inshore to nearshore and nearshore to offshore or deeper waters.
Taphonomy
Modes of preservation:body,concretion
Size of fossils:macrofossils
Collection methods and comments
Collection methods:field collection
Reason for describing collection:paleoecologic analysis
Collection method comments: COLLECTOR: Tanable et al. (1977). REPOSITORY: Unknown repository.
Taxonomic list comments:COVERAGE: Not exhaustive, only including ammonites, other taxa no listed, but mentioned (i.e. ostreids, trigonians, Glycymeris, drifted plant remains). NOMENCLATURE: Not authoritative publication, but apparently precise nomenclature.
Metadata
Database number:69171
Authorizer:A. Hendy Enterer:A. Hendy
Research group:marine invertebrate
Created:2007-02-20 10:48:05 Last modified:2025-02-22 15:12:02
Access level:the public Released:2007-02-20 10:48:00
Creative Commons license:CC0
Reference information

Primary reference:
19937. K. Tanabe. 1979. Paleoecological analysis of ammonoid assemblages in the Turonian Scaphites facies of Hokkaido, Japan. Palaeontology 22(3):609-630 [A. Hendy/A. Hendy]