Loreto Formation

Loreto Formation (Chile)

Loreto Formation (Spanish: Formación Loreto) is a sedimentary formation of Late Eocene age in the southernmost Magallanes Basin. It overlies the Leña Dura Formation and the contact with an overlying formation is not observed.^[1] From 2013 to 2020 its coals were mined in Invierno mine, Riesco Island.^[2]^[3]^[4]

Description

The formation contains fossil wood, leaf imprints and palynomorphs.^[5] Also fossil fish of Striatolamia macrota and Ischyodus dolloi and indeterminate Spheniscidae fossils have been found in the formation.^[6]^[7]

The formation crops out in Brunswick Peninsula and Sierra Baguales among other places.^[8]

References

^ Torres et al., 2009, p.2
^ "Los errores y contradicciones del caso Mina Invierno". Guía minera de Chile (in Spanish). Retrieved 2023-04-06.
^ Pozo B., Andrés (2014-08-11). "El silencioso primer año de Mina Invierno". Diario Financiero (in Spanish). Retrieved 2023-03-15.
^ González Encina, Verónica (2022-03-08). "Copec concreta la venta de su participación en Mina Invierno". Reporte Minero (in Spanish). Retrieved 2022-06-08.
^ Otero et al., 2012
^ Salaberry et al., 2010, p.1062
^ Rio de las Minos at Fossilworks.org
^ Bostelmann et al., 2012

Bibliography

Bostelmann, Enrique; Jacobus P. Le Roux; Ana Vasquez; Nestor Gutiérrez; José Luis Oyarzún; Catalina Carreño; Teresa Torres; Rodrigo Otero, and Andrea Llanos, C. Mark Fanning, Sven N. Nielsen and Francisco Hervé. 2012. [[1] A revised lithostratigraphy of the Sierra Baguales, Magallanes Basin], 698–700. XIII Congeso Geológico Chileno. Accessed 2019-02-15.
Otero, Rodrigo A.; Teresa Torres; Jacobus P. Le Roux; Francisco Hervé; C. Mark Fanning; Roberto E. Yuri Yáñez, and David Rubilar Rogers. 2012. A Late Eocene age proposal for the Loreto Formation (Brunswick Peninsula, southernmost Chile), based on fossil cartilaginous fishes, paleobotany and radiometric evidence. Andean Geology 39. 180–200. Accessed 2019-02-15.
Sallaberry, M.A.; R.E. Yury Yáñez; R.A. Otero; S. Soto Acuña, and T.G. Torres. 2010. Eocene birds from the western margin of southernmost South America. Journal of Paleontology 84. 1061–1070. Accessed 2019-02-15.
Torres, T.; H. Meón; R. Otero, and H. Galleguillos. 2009. Palinoflora y macroflora de la Formación Loreto, Punta Arenas, Región de Magallanes, Chile, 1–4. XII Congreso Geológico Chileno. Accessed 2019-02-15.

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.