Arroyo Las Paredes, LP 2, San Lucas Formation, Michoacan: Early/Lower Barremian, Mexico
List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Cephalopoda
- Hamulinidae
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Hamulina sp.
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2 specimens | ||||||
Cephalopoda
- Ammonitida
- Pulchelliidae
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Nicklesia sp.
Hyatt 1903
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7 specimens | ||||||
Subpulchellia sp.
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2 specimens | ||||||
Cephalopoda
- Ammonitida
- Leptoceratoididae
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Karsteniceras sp.
Royo-Gomez 1945
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21 specimens | ||||||
see common names |
Geography
Country: | Mexico |
Coordinates: | 18.6° North, 100.8° West (view map) |
Paleocoordinates: | 16.8° North, 56.2° West |
Basis of coordinate: | stated in text |
Geographic resolution: | small collection |
Time
Period: | Cretaceous | Epoch: | Early/Lower Cretaceous |
Stage: | Barremian | 10 m.y. bin: | Cretaceous 2 |
Key time interval: | Early/Lower Barremian | ||
Age range of interval: | 125.77000 - 121.40000 m.y. ago |
Stratigraphy
Formation: | San Lucas | Member: | Terrero Prieto | ||
Local section: | Arroyo Las Paredes | Local bed: | LP 2 | ||
Local order: | bottom to top | ||||
Stratigraphic resolution: | bed | ||||
Stratigraphy comments: early Early Barremian; lower part: Taveraidiscus hugii auctorum zone, upper part: Nicklesia pulchella zone; Arroyo Las Paredes Section is a 11.5 m thick unit |
Lithology and environment
Primary lithology: | lithified sandstone |
Includes fossils? | Y |
Lithology description: well-bedded dark gray to yelloish volcanic sandstones, with scattered radiolarian-type siliceous bioclasts. Flysch deposit | |
Environment: | submarine fan |
Geology comments: a distinct shallow marine shelf within a tectonically active area, oxygen-deficient bottom waters |
Taphonomy
Size of fossils: | macrofossils |
Preservation of anatomical detail: | variable |
Collection methods and comments
Collection methods: | selective quarrying,field collection |
Reason for describing collection: | paleoecologic analysis |
Taxonomic list comments:proliferation of middle-water depth ammonites |
Metadata
Database number: | 60777 | ||
Authorizer: | W. Kiessling | Enterer: | U. Merkel |
Modifier: | U. Merkel | Research group: | marine invertebrate |
Created: | 2006-05-23 03:02:09 | Last modified: | 2006-05-23 07:38:52 |
Access level: | the public | Released: | 2006-05-23 03:02:09 |
Creative Commons license: | CC BY |
Reference information
Primary reference:
17472. | R. Barragan, C. Gonzalez-Arreola, and A. B. Villasenor. 2004. Palaeoecological significance of Barremian ammonite assemblages and facies variations from Southwest Mexico. Lethaia 37:223-234 [W. Kiessling/U. Merkel] |