Coquimbo Formation

Coquimbo Formation (Spanish: Formación Coquimbo) is a Miocene to Middle Pleistocene sedimentary formation located in Coquimbo Region in Norte Chico, Chile. The lowermost unit belongs to the lower Miocene, with the third-deepest unit dated at 11.9 ± 1.0 Ma. The uppermost unit of the formation is estimated at 1.2 Ma. In the area of Tongoy, the Coquimbo Formation was deposited in an ancient bay that was formed in a graben or half-graben, with a normal fault dipping east. Sea level changes during the Holocene have caused erosion to cut several marine terraces into the formation.[1]

Coquimbo Formation Stratigraphic range: Miocene–Mid Pleistocene ~23–1.2 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Underlies	Alluvium
Overlies	Liman Formation
Thickness	63 m (207 ft)
Lithology
Primary	Conglomerate, sandstone, siltstone, shale and coquina
Other	Clay lenses, terra rossa
Location
Coordinates	30°20′21″S 71°32′03″W
Approximate paleocoordinates	30.1°S 70.3°W
Region	Coquimbo Region
Country	Chile
Extent	Tongoy Bay
Type section
Named for	Coquimbo
Coquimbo Formation (Chile)

Fossil content

The following fossils have been found in the formation:

SALMA	Group	Fossils	Notes
Montehermosan	Mammals	Delphinus domeykoi, Megaptera hubachi, Pliopontos sp., ?Squalodon sp., Balaenidae indet.	[2][3] [4]
	Birds	cf. Palaeospheniscus sp., Spheniscus sp., Diomedeidae indet., Spheniscidae indet.	[5][6]
	Fish	Carcharodon carcharias	[7]
Mayoan		Cosmopolitodus hastalis	[8]

See also

• Cerro Ballena
• Elqui-Limarí Batholith
• Caleta Herradura Formation
• Navidad Formation
• Pisco Formation

References

1. Le Roux, J.P.; Olivares, Danisa M.; Nielsen, Sven N.; Smith, Norman D.; Middleton, Heather; Fenner, Juliane; Ishman, Scott E. (2006). "Bay sedimentation as controlled by regional crustal behaviour, local tectonics and eustatic sea-level changes: Coquimbo Formation (Miocene–Pliocene), Bay of Tongoy, central Chile" (PDF). Sedimentary Geology. 184 (1–2): 133–153. Bibcode:2006SedG..184..133L. doi:10.1016/j.sedgeo.2005.09.023. Retrieved 11 April 2016.
2. Coquimbo at Fossilworks.org
3. Bahia de Guayacan at Fossilworks.org
4. Bahia Herradura at Fossilworks.org
5. La Cantera at Fossilworks.org
6. Chanaral de Aceituno at Fossilworks.org
7. Tongoy area Unit 11 at Fossilworks.org
8. Tongoy area Unit 4 at Fossilworks.org

Further reading

• C. Acosta Hospitaleche, J. Canto, and C. P. Tambussi. 2006. Pingüinos (Aves, Spheniscidae) en Coquimbo (Mioceno Medio-Plioceno Tardio), Chile y su vinculación con las corrientes oceánicas. Revista Española de Paleontología 21(1):115-122
• Staig, Felipe; Sebastián Hernández; Patricio López; Jaime A. Villafaña; Cristian Varas; Luis Patricio Soto, and Jorge D. Carrillo Briceño. 2015. Late Neogene Elasmobranch fauna from the Coquimbo Formation, Chile. Revista Brasileira de Paleontologia 18. 261–272. Accessed 2017-08-15.