El Molino Formation

For other uses, see Molino Formation.

El Molino Formation
Stratigraphic range: Maastrichtian ~70–66  Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Unit of	Puca Group
Underlies	Santa Lucía Formation
Overlies	Chaunaca Formation
Lithology
Primary	Sandstone
Other	Limestone
Location
Coordinates	19°30′S65°48′W / 19.5°S 65.8°W / -19.5; -65.8
Approximate paleocoordinates	22°00′S51°48′W / 22.0°S 51.8°W / -22.0; -51.8
Region	Cochabamba, Chuquisaca & Potosí Departments
Country	Bolivia
Extent	Altiplano & Potosí Basins
El Molino Formation (Bolivia)

The El Molino Formation is a Maastrichtian geologic formation pertaining to the Puca Group of central Bolivia. The formation comprises fine-grained sandstones and sandy limestones with stromatolites deposited in a shallow marine to lacustrine environment. The formation has provided fossils of Dolichochampsa minima , ^[1] and ichnofossils of Ankylosauria indet., Ornithopoda indet., Theropoda indet. and Titanosauridae indet. ^{[2] [3] [4]} The tracksite of Cal Orcko is the best known example of the ichnofossil locations of the formation. The ichnofossil of Ligabueichnum bolivianum may be attributed to an ankylosaur. ^[5] The fossil fish species Dasyatis molinoensis is named after the formation.

Fossil content

Other fossils retrieved from the formation are: ^[6]

• Coelodus toncoensis
• Dagetella sudamericana
• Dasyatis branisai , D. molinoensis , D. schaefferi
• Gasteroclupea branisai
• Ischyrhiza hartenbergeri
• Latinopollia suarezi
• Lepidotyle enigmatica
• Ligabueichnum bolivianum ^[5]
• Noterpeton bolivianum
• Phaerodusichthys taverni
• Pucabatis hoffstetteri
• Pucapristis branisi
• Stephanodus minimus
• Lepidosiren cf. paradoxa
• Andinichthys sp.
• Ceratodus sp.
• Enchodus sp.
• Lepisosteus sp.
• Pucalithus sp. ^[7]
• Rhineastes sp.
• Santosius sp.
• Anura indet.
• Coelurosauria indet.
• Crocodylia indet.
• Dryolestidae indet.
• Eutheria indet.
• cf. Cyprinodontiformes indet.
• Gymnophiona indet.
• Heterotidinae indet.
• ?Madtsoiidae indet.
• Podocnemididae indet.
• Pycnodontidae indet.
• Sauropoda indet.
• Siluriformes indet.
• Tetragonopterinae indet.

See also

• List of fossiliferous stratigraphic units in Bolivia
• List of stratigraphic units with dinosaur tracks
  • List of stratigraphic units with theropod tracks
• Cajones Formation
• Chaunaca Formation
• La Puerta Formation
• Toro Toro Formation

References

1. Buffetaut, 1987
2. Lockley et al., 2002, p.389
3. La Palca village at Fossilworks.org
4. Cal Orcko tracksite at Fossilworks.org
5. Leonardi, 1994, p.39
6. Pajcha Pata at Fossilworks.org
7. Leonardi, 1994, p.40

Bibliography

• Buffetaut, É (1987), "Occurrence of the crocodilian Dolichochampsa minima (Eusuchia, Dolichochampsidae) in the El Molino Formation of Bolivia", Bulletin de la Société Belge de Géologie , 96 (2): 195–199
• Leonardi, Giuseppe (1994), Annotated Atlas of South America Tetrapod Footprints (Devonian to Holocene) with an appendix on Mexico and Central America, Ministerio de Minas e Energia - Companhia de Pesquisa de Recursos Minerais, Geological Service of Brazil, pp. 1–248, retrieved 2019-03-25
• Lockley, M.G.; Schulp, A.S.; Meyer, C.A.; Leonardi, G.; Mamani, D.K. (2002), "Titanosaurid trackways from the Upper Cretaceous of Bolivia: evidence for large manus, wide-gauge locomotion and gregarious behaviour", Cretaceous Research , 23 (3): 383–400, Bibcode:2002CrRes..23..383L, doi:10.1006/cres.2002.1006 , retrieved 2019-03-03