Ayacara Formation

Ayacara Formation
Stratigraphic range: Early–Middle Miocene ~21.8–17.6 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Thickness	at least 800 m (2,600 ft)
Lithology
Primary	Sandstone, siltstone, conglomerate
Location
Coordinates	Ayacara Formation (Chile)

The Ayacara Formation is a sedimentary formation made up of interbedded sand and siltstone cropping out around Hornopirén and Ayacara Peninsula in western Los Lagos Region, Chile. Less common rocks are tuff and conglomerate. The formation dates to the Early and Middle Miocene (no earlier than 21.8–17.6 million years ago) when it deposited during a marine transgression.^[1]

References

^ Encinas, Alfonso; Folguera, Andrés; Bechis, Florencia; Finger, Kenneth L.; Zambrano, Patricio; Pérez, Felipe; Benarbé, Pablo; Tapia, Francisca; Riffo, Ricardo; Buatois, Luis; Orts, Darío; Nielsen, Sven N.; Valencia, Victor V.; Cituño, José; Oliveros, Verónica; De Girolamo Del Mauro, Lizet; Ramos, Víctor A. (2018). "The Late Oligocene–Early Miocene Marine Transgression of Patagonia". In Folguera, A.; Contreras Reyes, E.; Heredia, N.; et al. (eds.). The Evolution of the Chilean-Argentinean Andes. Springer. pp. 443–474. ISBN 978-3-319-67774-3.

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.