Lefipán
Description
Source: Wikipédia
The Lefipán Formation is a Maastrichtian to Danian, straddling the Cretaceous-Paleogene boundary, geologic formation of the Cañadón Asfalto Basin in Chubut Province, Patagonia, Argentina. The up to 380 metres (1,250 ft) thick stratigraphic unit comprises mudstones, sandstones, siltstones and conglomerates, sourced from the North Patagonian Massif and deposited in a deltaic to shallow marine environment with a strong tidal influence. The basin that in those times was connected to the widening South Atlantic Ocean with a seaway connection to the Austral Basin and possibly with the Pacific Ocean.
The formation has provided unique fossil flora assemblages dating to the Cretaceous and Paleogene ages, and are characteristic of the early Cenozoic after the extinction of the dinosaurs. The occurrence of the same taxa in the Maastrichtian and Danian successions suggests that the Cretaceous-Paleogene extinction event did not affect aquatic plant communities, which retained approximately similar structure and composition during the transition between the latest Maastrichtian and the earliest Paleocene. Insect predation on fossil leaves shows a considerably more rapid recovery from the extinction in event in Patagonia (about 4 Ma) than in the Western Interior of North America, estimated at 9 million years.
Fossils of the mammal Cocatherium, the oldest known marsupial or any therian mammal in the Southern Hemisphere, and fish; Hypolophodon patagoniensis and shark teeth were found in the Danian section of the formation. The Danian part of the succession contains fossil flora of Lactoridaceae, presently a monotypic family restricted to the subtropical forests of the Juan Fernández Archipelago in the South Pacific Ocean, offshore Chile. The latest Cretaceous lower section of the formation contains fossils of a plesiosaur; Aristonectes parvidens. The genus Lefipania padillae and species Cocatherium lefipanum and Araucaria lefipanensis were named after the formation.
Découvertes
Source: The Paleobiology Database
Site(s) correspondant(s) à cette formation: 1
Paso del Sapo, Cerro Azul : Chubut - ? Publication(s)
La base comprend 3 publication(s).
Source: The Paleobiology Database
- ↑1 2 S. Apesteguia and A. Cambiaso. 1999. Hallazgo de hadrosaurios en la Formación Paso del Sapo (Campaniano–Maastrichtiano, Chubut): otra localidad del "Senoniano lacustre" [Discovery of hadrosaurs in the Paso del Sapo Formation (Campanian–Maastrichtian): another locality in the "lacustrine Senonian". XV Jornadas Argentinas de Paleontología de Vertebrados, Resúmenes. Ameghiniana 36(4 (suppl.)):5R
- ↑1 S. Apesteguía, A. Cambiaso, and F. Agnolin. 2012. Vertebrados de la Formacion Paso del Sapo (Campaniano/Maastrichtiano), Provincia de Chubut, Argentina [Vertebrates from the Paso del Sapo Formation (Campanian/Maastrichtian), Chubut province, Argentina]. Ameghiniana 49(3):395-400 (https://doi.org/10.5710/AMGH.v49i3(358))
- ↑1 P. Cruzado-Caballero, L. S. Filippi, and A. H. Méndez, A. C. Garrido, I. Díaz-Martínez. 2018. First ornithopod remains from the Bajo de la Carpa Formation (Santonian, Upper Cretaceous), northern Patagonia, Argentina. Cretaceous Research 83:182-193 (https://doi.org/10.1016/j.cretres.2017.07.022)