Loreto Formation

Loreto Formation
Stratigraphic range: Priabonian (Divisaderan)
Type	Geological formation
Underlies	not observed
Overlies	Leña Dura Formation
Lithology
Primary	Sandstone
Other	Conglomerate, coal
Location
Coordinates	53.1°S 71.1°W / -53.1; -71.1
Approximate paleocoordinates	55.3°S 61.4°W / -55.3; -61.4
Region	Magallanes y la Antártica Chilena Region
Country	Chile
Extent	Magallanes Basin
Type section
Named by	Hoffstetter et al.
Year defined	1957
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

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

Bibliography

• Bostelmann, Enrique; Le Roux, Jacobus P.; Vasquez, Ana; Gutiérrez, Nestor; Oyarzún, José Luis; Carreño, Catalina; Torres, Teresa; Otero, Rodrigo; Llanos, C. Mark Fanning, Sven N. Nielsen and Francisco Hervé, Andrea (2012), A revised lithostratigraphy of the Sierra Baguales, Magallanes Basin (PDF), XIII Congeso Geológico Chileno, pp. 698–700, archived from the original (PDF) on 2018-11-03, retrieved 2019-02-15
• Otero, Rodrigo A.; Torres, Teresa; Le Roux, Jacobus P.; Hervé, Francisco; Fanning, C. Mark; Yuri Yáñez, Roberto E.; Rubilar Rogers, David (2012), "A Late Eocene age proposal for the Loreto Formation (Brunswick Peninsula, southernmost Chile), based on fossil cartilaginous fishes, paleobotany and radiometric evidence" (PDF), Andean Geology, 39: 180–200, doi:10.5027/andgeoV39N1-a09, retrieved 2019-02-15
• Sallaberry, M.A.; Yury Yáñez, R.E.; Otero, R.A.; Soto Acuña, S.; Torres, T.G. (2010), "Eocene birds from the western margin of southernmost South America" (PDF), Journal of Paleontology, 84 (6): 1061–1070, Bibcode:2010JPal...84.1061S, doi:10.1666/09-157.1, retrieved 2019-02-15
• Torres, T.; Meón, H.; Otero, R.; Galleguillos, H. (2009), Palinoflora y macroflora de la Formación Loreto, Punta Arenas, Región de Magallanes, Chile (PDF), XII Congreso Geológico Chileno, pp. 1–4, retrieved 2019-02-15