Tanohata Fm Oj 5825-2 - Tanohata: Late Aptian, Japan

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Crinoidea - Isocrinida - Isocrinidae
see common names

Geography
Country:Japan State/province:Iwate
Coordinates: 40.1° North, 141.8° East (view map)
Paleocoordinates:48.3° North, 151.0° East (Wright 2013)
Basis of coordinate:estimated from map
Geographic resolution:outcrop
Time
Period: Cretaceous Epoch: Early Cretaceous
10 m.y. bin: Cretaceous 2-3
Key time interval: Late Aptian
Age range of interval: 119.57 - 113.2 m.y. ago
Stratigraphy
Geological group:Miyako Formation:Tanohata
Stratigraphic resolution:bed
Stratigraphy comments: Miyako group extends from Aptian - Albian. This collection comes from one of the uppermost Aptian formations in the group, but is the fm. immediately below the Hiraiga Fm. Specimens of the Isocrinus species reported here occur in the upper portions of the Tanohata Fm, 4 m below the contact with Hiraiga Fm.
Lithology and environment
Primary lithology:bioturbation lithified sandy siltstone
Lithology description: sandy siltstone, extensively bioturbated. disarticulated colums and brachials occur throughout the sediment. specimens are better preserved in siltstone than those from sandstone.
Environment:transition zone/lower shoreface
Geology comments: relatively shallow, quiet water
Taphonomy
Modes of preservation:body,original calcite
Size of fossils:macrofossils
Preservation of anatomical detail:variable
Abundance in sediment:few
Articulated whole bodies:none
Disassociated major elements:many
Disassociated minor elements:many
Collection methods and comments
Collection excludes:some macrofossils
Collection methods:field collection
Reason for describing collection:taxonomic analysis
Taxonomic list comments:specimens appear to be stored at University Museum, University of Tokyo
Metadata
Database number:65652
Authorizer:A. Miller Enterer:C. Ferguson
Research group:marine invertebrate
Created:2006-09-23 19:20:10 Last modified:2025-02-22 15:12:02
Access level:the public Released:2006-09-23 19:20:09
Creative Commons license:CC0
Reference information

Primary reference:

18878. T. Oji. 1985. Early Cretaceous Isocrinus from Northeast Japan. Palaeontology 28(4):629-642 [A. Miller/C. Ferguson]