Coquimbo Formation

Geological formation in Chile

Coquimbo Formation
Stratigraphic range: Miocene–Mid Pleistocene ~23–1.2 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Marine terrace exposing strata of the Coquimbo Formation, at Caleta Hornos
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	Coquimbo Formation (Chile)

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]

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	Fish	Cosmopolitodus hastalis	^[8]

References

^ 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.
^ Coquimbo at Fossilworks.org
^ Bahia de Guayacan at Fossilworks.org
^ Bahia Herradura at Fossilworks.org
^ La Cantera at Fossilworks.org
^ Chanaral de Aceituno at Fossilworks.org
^ Tongoy area Unit 11 at Fossilworks.org
^ Tongoy area Unit 4 at Fossilworks.org

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; Hernández, Sebastián; López, Patricio; Villafaña, Jaime A.; Varas, Cristian; Soto, Luis Patricio; Carrillo Briceño, Jorge D. (2015), "Late Neogene Elasmobranch fauna from the Coquimbo Formation, Chile", Revista Brasileira de Paleontologia, 18 (2): 261–272, doi:10.4072/rbp.2015.2.07, retrieved 2017-08-15

Geology of Chile

Terranes

Sedimentary
formations
and groups

Cretaceous	Baños del Flaco Fm. Cerro Colorado Fm. Chacarilla Fm. Chañarcillo Gp. Coihaique Gp. Divisadero Gp. Dorotea Fm. Hornitos Fm. La Liga Fm. Ñirehuao Fm. Punta del Cobre Fm. Purilactis Gp. Quiriquina Fm. Viñita Fm. Way Gp. Zapata Fm.
Jurassic	Chacarilla Fm. Coihaique Gp. Ibáñez Fm. La Liga Fm. La Negra Fm. Nacientes del Biobío Fm. Nacientes del Teno Fm. Pan de Azúcar Fm. Tobífera Fm.
Triassic	Canto del Agua Fm. Choiyoi Gp. Panguipulli Fm. Santa Juana Fm. Tralcán Fm.