Dorotea Formation

Dorotea Formation
Dorotea Formation
Stratigraphic range: Late Campanian-Maastrichtian; ~72–66 Ma PreꞒ Ꞓ O S D C P T J K Pg N B V H B Apt. Albian C T C S Cam. M
Type	Geological formation
Underlies	Man Aike Formation
Overlies	Tres Pasos Formation
Thickness	100–350 m (330–1,150 ft)
Lithology
Primary	Sandstone, claystone
Other	Conglomerate
Location
Coordinates	50°42′S 72°30′W / 50.7°S 72.5°W
Approximate paleocoordinates	52°54′S 60°30′W / 52.9°S 60.5°W
Region	Magallanes Region
Country	Chile
Extent	Río de Las Chinas Valley, Magallanes Basin
Type section
Named for	Sierra Dorotea
Named by	Katz
Year defined	1963
	Dorotea Formation (Chile)

The Dorotea Formation is a geological formation in the Río de Las Chinas Valley of the Magallanes Basin in Patagonian Chile whose strata date back to the Campanian to Maastrichtian of the Late Cretaceous.

Description

The Dorotea Formation was first described by Katz in 1963. The formation comprises sandstones with frequent conglomerate lenses, concretionary levels and claystones. The Dorotea Formation includes calcareous sandstones with abundant marine invertebrate and fragmentary vertebrate fossils. Hervé et al. (2004) obtained a maximum radiometric age of 67.4 ± 1.5 Ma from detrital zircons contained in sandstones of the Dorotea Formation. Near the top of the formation is an iridium anomaly, correlated with the Cretaceous–Paleogene boundary; this is the southernmost K–Pg boundary site known from South America.

The mudstones and sandstones of the formation were deposited in a fluvial environment. The formation conformably overlies the Tres Pasos Formation and is unconformably overlain by the Lutetian to Bartonian Man Aike Formation. The thickness of the formation ranges from 100 metres (330 ft) in the Sierra Baguales in the north to 350 metres (1,150 ft) in the eponymous Sierra Dorotea in the south.

Fossil content

The following fossils were reported from the formation:

Amphibians


Amphibians of Dorotea Formation
Taxa	Species	Material	Notes	Images
Anura	Indeterminate		A frog

Reptiles


Reptiles of Dorotea Formation
Taxa	Species	Locality	Material	Notes	Images
Aristonectinae	Indeterminate
Aristonectes	A. sp.
Yaminuechelys	cf. Yaminuechelys sp.
Panchelidae	Indeterminate	Saurópodo sector (Section SP-17).	Distal fragment of right humerus and distal end of right femur.
Elasmosauridae	Indeterminate

Dinosaurs

Ornithischians


Ornithischians of Dorotea Formation
Taxa	Species	Locality	Material	Notes	Images
Gonkoken	G. nanoi	Loma Koken	Several incomplete specimens belonging to individuals of different ages	A hadrosauroid
Ornithischia	Indeterminate
Stegouros	S. elengassen		CPAP-3165 (holotype), a holotype consists of a relatively complete skeleton with a skull and lower jaws.	A parankylosaur

Saurischians


Saurischians of Dorotea Formation
Taxa	Species	Material	Notes	Images
Enantiornithes	Indeterminate
Megaraptoridae	Indeterminate
Ornithurae	Indeterminate
Sauropoda	Indeterminate
Unenlagiinae	Indeterminate
Theropoda	Indeterminate

Mammals


Mammals of Dorotea Formation
Taxa	Species	Locality	Material	Notes	Images
Magallanodon	M. baikashkenke	Mammal quarry from the Río de Las Chinas valley	A first lower left molariform	A gondwanathere
Orretherium	O. tzen	Mammal quarry from the Río de Las Chinas valley	A fragmented lower jaw.	A mesungulatid mammal
Mammalia	Indeterminate
Yeutherium	Y. pressor	'Black Bone' Locality	A left maxilla fragment with M1, roots of M2 and mesial roots of M3.	A subantarctic reigitheriidae mammal

Fish


Fish of Dorotea Formation
Taxa	Species	Material	Notes	Images
Ischyrhiza	I. chilensis
Carcharias	C. sp.
Serratolamna	Indeterminate

Invertebrates


Invertebrates of Dorotea Formation
Taxa	Species	Locality	Material	Notes	Images
Dorotheus	Dorotheus guidensis
Pterotrigonia	P. cazadoriana
Gunnarites	G. sp.
Pachydiscus	P. aff. gollevilensis

References

↑ Dorotea Formation at Fossilworks.org
1 2 3 4 Otero et al., 2009
↑ Manríquez, Leslie M. E.; Krahl, Guilherme; Carvalho, Marcelo A.; Lavina, Ernesto L. C.; Santiago, Gustavo; Bom, Marlone H. H.; Fauth, Gerson; Leppe, Marcelo (October 2024). "The K/Pg event at high southern latitudes: New evidence from continental deposits in the Magallanes/Austral Basin, Patagonia, South America". Cretaceous Research. 162 105931. Bibcode:2024CrRes.16205931M. doi:10.1016/j.cretres.2024.105931.
↑ Goin et al., 2020, p.9
1 2 3 4 Otero et al., 2015, p.240
↑ Río de las Chinas Valley at Fossilworks.org
1 2 3 4 5 6 7 Alarcón Muñoz et al., 2020
1 2 Otero et al., 2015
↑ Alarcón-Muñoz, Jhonatan; Vargas, Alexander O.; Püschel, Hans P.; Soto-Acuña, Sergio; Manríquez, Leslie; Leppe, Marcelo; Kaluza, Jonatan; Milla, Verónica; Gutstein, Carolina S.; Palma-Liberona, José; Stinnesbeck, Wolfgang; Frey, Eberhard; Pino, Juan Pablo; Bajor, Dániel; Núñez, Elaine (2023-06-16). "Relict duck-billed dinosaurs survived into the last age of the dinosaurs in subantarctic Chile". Science Advances. 9 (24) eadg2456. Bibcode:2023SciA....9G2456A. doi:10.1126/sciadv.adg2456. ISSN 2375-2548. PMC 10275600. PMID 37327335.
1 2 3 4 5 Davis, Sarah N.; Soto-Acuña, Sergio; Fernández, Roy A.; Amudeo, Jared; Leppe, Marcelo A.; Rubilar-Rogers, David; Vargas, Alexander O.; Clarke, Julia A. (December 2022). "New records of Theropoda from a Late Cretaceous (Campanian-Maastrichtian) locality in the Magallanes-Austral Basin, Patagonia, and insights into end Cretaceous theropod diversity". Journal of South American Earth Sciences. 122 104163. doi:10.1016/j.jsames.2022.104163. S2CID 254850180.
1 2 Goin et al., 2020
↑ Martinelli, A. G.; Soto-Acuña, S.; Goin, F. J.; Kaluza, J.; Bostelmann, J. E.; Fonseca, P. H. M. F.; Reguero, M. A.; Leppe, M.; Vargas, A. O. (2021). "New cladotherian mammal from southern Chile and the evolution of mesungulatid meridiolestidans at the dusk of the Mesozoic era". Scientific Reports. 11 (7594): 7594. Bibcode:2021NatSR..11.7594M. doi:10.1038/s41598-021-87245-4. PMC 8027844. PMID 33828193.
↑ Püschel, Hans P.; Martinelli, Agustin G.; Soto-Acuña, Sergio; Ortiz, Héctor; Leppe, Marcelo; Vargas, Alexander O. (August 2025). "A subantarctic reigitheriid and the evolution of crushing teeth in these enigmatic Mesozoic mammals". Proceedings of the Royal Society B: Biological Sciences. 292 (2052) 20251056. doi:10.1098/rspb.2025.1056. hdl:11336/272519. PMID 40763811.
↑ Kuschel, 1959

Bibliography

Alarcón-Muñoz, Jhonatan; Soto-Acuña, Sergio; Manríquez, Leslie M.E.; Fernández, Roy A.; Bajor, Dániel; Guevara, Juan Pablo; Suazo Lara, Felipe; Leppe, Marcelo A.; Vargas, Alexander O. (October 2020). "Freshwater turtles (Testudines: Pleurodira) in the Upper Cretaceous of Chilean Patagonia". Journal of South American Earth Sciences. 102 102652. Bibcode:2020JSAES.10202652A. doi:10.1016/j.jsames.2020.102652.
Goin, Francisco J.; et, al (2020), "First Mesozoic Mammal from Chile: the southernmost record of a Late Cretaceous Gondwanatherian" (PDF), Boletín del Museo Nacional de Historia Natural, Chile, 69 (1): 5–31, doi:10.54830/bmnhn.v69.n1.2020.8, retrieved 2020-06-12
Goin, Francisco J.; Martinelli, Agustín G.; Soto-Acuña, Sergio; Vieytes, Emma C.; Manríquez, Leslie M. E.; Fernández, Roy A.; Pino, Juan Pablo; Trevisan, Cristine; Kaluza, Jonatan; Reguero, Marcelo A.; Leppe, Marcelo; Ortiz, Héctor; Rubilar-Rogers, David; Vargas, Alexander O. (28 June 2020). "Primer mamífero Mesozoico de Chile: el registro más austral de un gondwanaterio del Cretácico tardío". Boletín Museo Nacional de Historia Natural. 69 (1): 5–31. doi:10.54830/bmnhn.v69.n1.2020.8.
Otero, Rodrigo A.; Soto-Acuña, Sergio; Salazar S., Christian; Oyarzún, José Luis (29 May 2015). "Nuevos elasmosáuridos (Sauropterygia, Plesiosauria) del Cretácico Superior de la Cuenca de Magallanes, Patagonia Chilena: Evidencia de recambio faunístico durante el Maastrichtiano a lo largo de la Provincia Biogeográfica Weddelliana". Andean Geology. 42 (2). Bibcode:2015AndGe..42b...5O. doi:10.5027/andgeoV42n2-a05.
Otero, Rodrigo A; Suárez, Mario E; Le Roux, Jacobus P (July 2009). "First record of Elasmosaurid Plesiosaurs (Sauropterygia: Plesiosauria) in upper levels of the Dorotea Formation, Late Cretaceous (Maastrichtian), Puerto Natales, Chilean Patagonia". Andean Geology. 36 (2). Bibcode:2009AndGe..36b...8O. doi:10.4067/S0718-71062009000200008.
Kuschel, G (1959), "Un curculionido del Cretácico Superior - primer insecto fósil de Chile", Investigaciones Zoológicas Chilenas, 5: 49–54

[FWDorotea-1] Dorotea Formation at Fossilworks.org

[Otero2009-2] 1 2 3 4 Otero et al., 2009

[3] Manríquez, Leslie M. E.; Krahl, Guilherme; Carvalho, Marcelo A.; Lavina, Ernesto L. C.; Santiago, Gustavo; Bom, Marlone H. H.; Fauth, Gerson; Leppe, Marcelo (October 2024). "The K/Pg event at high southern latitudes: New evidence from continental deposits in the Magallanes/Austral Basin, Patagonia, South America". Cretaceous Research. 162 105931. Bibcode:2024CrRes.16205931M. doi:10.1016/j.cretres.2024.105931.

[Goin2020-p9-4] Goin et al., 2020, p.9

[Otero2015-p240-5] 1 2 3 4 Otero et al., 2015, p.240

[FWRioLasChinas-6] Río de las Chinas Valley at Fossilworks.org

[Alarcon2020-7] 1 2 3 4 5 6 7 Alarcón Muñoz et al., 2020

[Otero2015-8] 1 2 Otero et al., 2015

[Gonkoken-9] Alarcón-Muñoz, Jhonatan; Vargas, Alexander O.; Püschel, Hans P.; Soto-Acuña, Sergio; Manríquez, Leslie; Leppe, Marcelo; Kaluza, Jonatan; Milla, Verónica; Gutstein, Carolina S.; Palma-Liberona, José; Stinnesbeck, Wolfgang; Frey, Eberhard; Pino, Juan Pablo; Bajor, Dániel; Núñez, Elaine (2023-06-16). "Relict duck-billed dinosaurs survived into the last age of the dinosaurs in subantarctic Chile". Science Advances. 9 (24) eadg2456. Bibcode:2023SciA....9G2456A. doi:10.1126/sciadv.adg2456. ISSN 2375-2548. PMC 10275600. PMID 37327335.

[:0-10] 1 2 3 4 5 Davis, Sarah N.; Soto-Acuña, Sergio; Fernández, Roy A.; Amudeo, Jared; Leppe, Marcelo A.; Rubilar-Rogers, David; Vargas, Alexander O.; Clarke, Julia A. (December 2022). "New records of Theropoda from a Late Cretaceous (Campanian-Maastrichtian) locality in the Magallanes-Austral Basin, Patagonia, and insights into end Cretaceous theropod diversity". Journal of South American Earth Sciences. 122 104163. doi:10.1016/j.jsames.2022.104163. S2CID 254850180.

[Goin2020-11] 1 2 Goin et al., 2020

[12] Martinelli, A. G.; Soto-Acuña, S.; Goin, F. J.; Kaluza, J.; Bostelmann, J. E.; Fonseca, P. H. M. F.; Reguero, M. A.; Leppe, M.; Vargas, A. O. (2021). "New cladotherian mammal from southern Chile and the evolution of mesungulatid meridiolestidans at the dusk of the Mesozoic era". Scientific Reports. 11 (7594): 7594. Bibcode:2021NatSR..11.7594M. doi:10.1038/s41598-021-87245-4. PMC 8027844. PMID 33828193.

[13] Püschel, Hans P.; Martinelli, Agustin G.; Soto-Acuña, Sergio; Ortiz, Héctor; Leppe, Marcelo; Vargas, Alexander O. (August 2025). "A subantarctic reigitheriid and the evolution of crushing teeth in these enigmatic Mesozoic mammals". Proceedings of the Royal Society B: Biological Sciences. 292 (2052) 20251056. doi:10.1098/rspb.2025.1056. hdl:11336/272519. PMID 40763811.

[Kuschel1959-14] Kuschel, 1959