Arroyo Las Paredes, LP 4, San Lucas Formation, Michoacan: Early/Lower Barremian, Mexico
List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
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Cephalopoda
- Hamulinidae
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Hamulina sp.
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4 specimens | ||||||
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Cephalopoda
- Ammonitida
- Oppeliidae
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Eoheteroceras sp.
Vasícek and Wiedmann 1994
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3 specimens | ||||||
| synonym of Oxycerites (Alcidellus) | |||||||
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Cephalopoda
- Ammonitida
- Leptoceratoididae
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Hamulinites sp.
Paquier 1900
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3 specimens | ||||||
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Karsteniceras sp.
Royo-Gomez 1945
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15 specimens | ||||||
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Cephalopoda
- Ammonitida
- Pulchelliidae
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Nicklesia sp.
Hyatt 1903
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2 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 4 | ||
| Local order: | bottom to top | ||||
| Stratigraphic resolution: | bed | ||||
| Stratigraphy comments: early Early Barremian; 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 siliceous and calcareous 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: | 60779 | ||
| Authorizer: | W. Kiessling | Enterer: | U. Merkel |
| Modifier: | U. Merkel | Research group: | marine invertebrate |
| Created: | 2006-05-23 03:17:39 | Last modified: | 2006-05-23 07:41:36 |
| Access level: | the public | Released: | 2006-05-23 03:17:39 |
| 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] |