The La Quinta Formation is a

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...

geologic

formation Formation may refer to: Linguistics * Back-formation, the process of creating a new lexeme by removing or affixes * Word formation, the creation of a new word by adding affixes Mathematics and science * Cave formation or speleothem, a secondary ...

which crops out in the

Cordillera de Mérida The Cordillera de Mérida is a mountain range, or massif, in northwestern Venezuela. The Cordillera de Mérida is a northeastern extension of the Andes Mountains and the most important branch of the Venezuelan Andes. The range runs approximately 4 ...

and

Serranía del Perijá The Serranía del Perijá, Cordillera de Perijá or Sierra de Perijá is a mountain range, an extension of the eastern Andean branch ( Cordillera Oriental), in northern South America, between Colombia and Venezuela, ending further north in the ...

of western

Venezuela Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...

and northeastern

Colombia Colombia, officially the Republic of Colombia, is a country primarily located in South America with Insular region of Colombia, insular regions in North America. The Colombian mainland is bordered by the Caribbean Sea to the north, Venezuel ...

. The formation is also present in the subsurface of the Cesar-Ranchería and

Maracaibo Basin The Maracaibo Basin, also known as Lake Maracaibo natural region, Lake Maracaibo depression or Lake Maracaibo Lowlands, is a foreland basin and one of the eight natural regions of Venezuela, found in the northwestern corner of Venezuela in South A ...

s. At its type locality near

La Grita La Grita is a town in the north west of Táchira state, Venezuela. It has a population of 80,000. Located in an Andean valley, La Grita has a beautiful natural setting and fertile land. The town includes colonial style houses and open plazas. ...

Táchira Táchira State (, ) is one of the 23 States of Venezuela, states of Venezuela. The state capital is San Cristóbal, Táchira, San Cristóbal. Táchira State covers a total surface area of and as of the 2011 census, had a population of 1,168,9 ...

, it consists of a basal

dacitic Dacite () is a volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides. It has a fine-grained (aphanitic) to porphyritic texture and is intermediate in composition between andesite and rhyolite. ...

tuff Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. Rock that contains greater than 75% ash is considered tuff, while rock co ...

followed by interlayered

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

siltstone Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility. Although its permeabil ...

s and rare

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

s.Barret ''et al.'', 2008, p.164

Dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...

remains including '' Laquintasaura'',Barret ''et al.'', 2014 '' Tachiraptor'', and '' Perijasaurus'' are among the fossils that have been recovered from the formation.Weishampel, ''et al.'' (2004). "Dinosaur distribution." Pp. 517-607 U–Pb zircon analysis demonstrates that the formation dates to 200.91+0.55 Ma at its base and a maximum age of 174.8 Ma.

Paleofauna

Regional correlations

Notes

References

Bibliography

* * Barrett, P. M., R. J. Butler, S. C. Moore-Fay, F. E. Novas, J. M. Moody, J. M. Clark, and M. R. Sänchez-Villagra. ‘Dinosaur Remains from the La Quinta Formation (Lower or Middle Jurassic) of the Venezuelan Andes’. Paläontologische Zeitschrift 82, no. 2 (2008): 163–177. * Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp. .

Maps

* * * * * * {{citation , last1=Hernández , first1=Marina , last2=Clavijo , first2=Jairo , year=2008 , title=Plancha 48 - La Jagua de Ibirico - 1:100,000 , url=https://drive.google.com/open?id=0BwFQPMJEi17QeGxwUUxmSHEwdm8 , publisher=

INGEOMINAS The Colombian Geological Survey (CGS) (; formerly known as INGEOMINAS) is a scientific agency of the Colombian government in charge of contributing to the socioeconomic development of the nation through research in basic and applied geosciences ...