IGM-2778, NW of Paredon: Early Paleocene, Mexico

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Bivalvia - Carditida - Carditidae
Venericardia sp. Lamarck 1801
Cephalopoda - Nautilida - Hercoglossidae
Cimomia haltomi (Aldrich 1931)
Gastropoda - Pleuroceridae
see common names

Geography
Country:Mexico State/province:Coahuila
Coordinates: 26.1° North, 100.8° West (view map)
Paleocoordinates:35.4° North, 72.9° West (Wright 2013)
Basis of coordinate:stated in text
Geographic resolution:outcrop
Time
Period: Paleogene Epoch: Paleocene
Stage: Danian 10 m.y. bin: Cenozoic 1
Key time interval: Early Paleocene
Age range of interval: 66 - 61.66 m.y. ago
Stratigraphy
Geological group:Difunta Formation:Potrerillos Member:Upper Mudstone
Stratigraphic resolution:bed
Stratigraphy comments: The Potrerillos Formation was subdivided into five members by McBride (1974), of which the collection is from the second highest, Upper Mudstone Member. Foraminifera in the lower members indicate a Maastrichtian age, while fossils in the upper members indicate a Paleocene age. At IGM 2778 a coarse calcarenite bed of light gray color occurs, nearly 2 m thick. Fossil remains are abundant and include transported remains of corals, gastropods, bivalves, shark teeth, and bone fragments.
Lithology and environment
Primary lithology:coarse,shelly/skeletal,gray lithified grainstone
Includes fossils?Y
Lithology description: Coarse calcarenite bed of light gray color occurs, nearly 2 m thick
Environment:shoreface
Geology comments: Sediments are interpreted as shoreface deposits.
Taphonomy
Modes of preservation:body
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: Studied material is deposited in the Museo de Paleontologia of the Instituto de Geologia, Universidad Nacional Autonoma de Mexico. Types are in the type collection and classified under the acronym IGM. The type locality is registered in the locality catalogue of the Museo de Paleontogia.
Taxonomic list comments:No exhuastive, but including some abundant and biostratigraphically significant taxa. Includes gastropods and bivalves.
Metadata
Database number:42469
Authorizer:A. Hendy Enterer:A. Hendy
Modifier:M. Clapham Research group:marine invertebrate
Created:2004-07-29 21:41:58 Last modified:2025-02-22 15:12:02
Access level:the public Released:2004-07-29 21:41:58
Creative Commons license:CC0
Reference information

Primary reference:
11301. F. J. Vega and M.D.C. Perrilliat. 1995. On some Paleocene invertebrates from the Potrerillos Formation (Difunta Group), northeastern Mexico. Journal of Paleontology 69(5):863-869 [A. Miller/A. Hendy/A. Hendy]

Secondary references:

11300 F. J. Vega, M.D.C. Perrilliat, and L.M. Mitre-Salazar. 1999. Paleocene ostreids from the Las Encinas Formation (Parras basin, Difunta Group), northeastern Mexico; stratigraphic implications. Geological Society of America Special Paper 340:105-110 [A. Miller/A. Hendy/A. Hendy]