Los Llanos
Description
Source: Wikipédia
Los Llanos Formation is a geological formation in the La Rioja Province, northwestern Argentina whose strata date back to the Campanian stage of the Late Cretaceous.
Los Llanos Formation over the years has been controversially described as ranging from Late Cretaceous to Miocene, but the Miocene succession was assigned to Las Mulitas Formation in 2019. The formation rests on top of the Early Permian Los Sauces and Patquía Formations and in parts on Ordovician crystalline basement. The maximum thickness is estimated at 150 metres (490 ft).
The sandstones and conglomerates of the formation were deposited ij a fluvial environment. The formation crops out in the Sanagasta geological park, where more than 90 titanosaurid nesting sites were discovered in Los Llanos Formation. The sites were encountered on top of areas characterized by hydrothermal activity as geysers and other vents, suggesting a preferred location for the incubation of the dinosaur eggs. Apart from fossil eggs, the formation has provided fossil flora and ostracods. The crocodyliform Llanosuchus, described in 2016 from the formation, was named after Los Llanos Formation.
Découvertes
Source: The Paleobiology Database
Site(s) correspondant(s) à cette formation: 2
4 km south of Tama village : La Rioja - Gral. Angel V. Penaloza 57573 76281 76302 Colozacán valley in the vicinity of Tunacata and Guasamayo, 4 km S of Tama village (Gral. Angel V. Penaloza department), W slope of Sierra de Los Llanos mountain range in the SE region of La Rioja province, type area for the Los Llanos Formation.- Colozacán Valley : La Rioja - Gral. Angel V. Penaloza 93160 CRILAR-Pv 506 comes from the main dinosaur quarry of the Colozacán Valley in the vicinity of Tunacata and Guasamayo, 3 km south of Tama village (General Ángel V. Peñaloza Department), western slope of Sierra de Los Llanos Mountain range in the southeastern region of La Rioja Province, Argentina.
Publication(s)
La base comprend 4 publication(s).
Source: The Paleobiology Database
- ↑1 2 L. E. Fiorelli, E. M. Hechenleitner, and D. Pol, J. M. Leardi, G. Grellet-Tinner. 2014. The first notosuchian crocodyliform from the Cretaceous of La Rioja, Argentina. XXVIII Jornadas Argentina de Paleontología de Vertebrados. Resúmenes. Ameghiniana 51(6 (suppl.)):10
- ↑1 L. E. Fiorelli, J. M. Leardi, and E. M. Hechenleitner, D. Pol, G. Basilici, G. Grellet-Tinner. 2016. A new Late Cretaceous crocodyliform from the western margin of Gondwana (La Rioja Province, Argentina). Cretaceous Research 60:194-209 (https://doi.org/10.1016/j.cretres.2015.12.003)
- ↑1 E. M. Hechenleitner, L. E. Fiorelli, and G. Grellet-Tinner, G. Basilici, L. Leuzinger. 2015. A new titanosaur nesting site from the Los Llanos Formation (Late Cretaceous, La Rioja, Argentina). XXIX Jornadas Argentinas de Paleontología de Vertebrados. Resúmenes. Ameghiniana 52(4 (suppl.)):23
- ↑1 2 H. Jiménez Velandia, M. D. Ezcurra, and M. E. Hechenleitner, G. Basilici, A. G. Martinelli, L. E. Fiorelli. 2025. A new late Cretaceous abelisaurid species from La Rioja Province, Northwestern Argentina. Ameghiniana 62(5):1-23 (https://doi.org/10.5710/AMGH.24.09.2025.3653)