Machinato Limestone, Ryukyu Group, Okinawa: Late Pleistocene, Japan

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Gastropoda - Trochidae
Trochus sp. Linnaeus 1758
see common names

Geography
Country:Japan State/province:Okinawa
Coordinates: 26.7° North, 128.0° East (view map)
Paleocoordinates:
Basis of coordinate:estimated from map
Geographic resolution:basin
Time
Period: Quaternary Epoch: Pleistocene
Stage: Late Pleistocene 10 m.y. bin: Cenozoic 6
Key time interval: Late Pleistocene
Age range of interval: 0.129 - 0.0117 m.y. ago
Stratigraphy
Geological group:Ryukyu Member:Machinato Limestone
Regional section:Okinawa
Stratigraphic resolution:formation
Stratigraphy comments: Some widely seperated, but supposedly synchronouys detrital limestones that thinly veneer older formations and fill former areas of relief are grouped together under the name Machinato Limestone. For the most part veneers consist of indurated foraminiferal sand. The Machinato Limestone reaches a maximum thickness of 100 ft, and comprises a basal conglomerate, indurated clay, and sand derived from the Shimajiri Formation. The matrix is foraminiferal sand containing fragmented molluscan shells.
Lithology and environment
Primary lithology: lithified sandy,conglomeratic "limestone"
Includes fossils?Y
Lithology description: Indurated foraminiferal sand, but also including a basal conglomerate, indurated clay, and sand derived from the Shimajiri Formation. The matrix is foraminiferal sand containing fragmented molluscan shells.
Environment:carbonate indet.
Glacial or sequence phase:transgressive
Geology comments: Shallow water carbonate environment? No specific paleoenvironmental data provided.
Taphonomy
Modes of preservation:body,original aragonite
Size of fossils:macrofossils
Collection methods and comments
Collection excludes:some macrofossils
Collection methods:selective quarrying,field collection
Reason for describing collection:taxonomic analysis
Collection method comments: Collections held in USNM and UGSG repositories.
Taxonomic list comments:Taxa described in text, but not listed for specific localities. Corals mentioned but no ID's reported.
Metadata
Database number:42382
Authorizer:A. Hendy Enterer:A. Hendy
Modifier:A. Hendy Research group:marine invertebrate
Created:2004-07-28 13:46:52 Last modified:2025-02-22 15:12:02
Access level:the public Released:2004-07-28 13:46:52
Creative Commons license:CC0
Reference information

Primary reference:

7337. F. S. MacNeil. 1960. Tertiary and Quaternary Gastropoda of Okinawa: A comparison of the late Miocene, Pliocene, and Pleistocene Gastropoda of Okinawa with related faunas of East Asia together with a resume of the geological setting of the fossiliferous deposits. United States Geological Survey Professional Paper 339:1-148 [A. Miller/C. Ferguson/P. Wagner]