The Jimol Formation ( es, Formación Jimol, N1j) is a fossiliferous

geological formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock expo ...

of the Cocinetas Basin in the northernmost department of La Guajira. The formation consists of

calcareous Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines. In zoology ''Calcareous'' is used as an a ...

lithic Lithic may refer to: *Relating to stone tools **Lithic analysis, the analysis of stone tools and other chipped stone artifacts **Lithic core, the part of a stone which has had flakes removed from it **Lithic flake, the portion of a rock removed to ...

and fossiliferous sandstones,

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.Blatt ''et al.'' 1980, ...

s and mudstones. The Jimol Formation dates to the

Neogene The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago (Mya) to the beginning of the present Quaternary Period Mya. ...

period;

Burdigalian The Burdigalian is, in the geologic timescale, an age or stage in the early Miocene. It spans the time between 20.43 ± 0.05 Ma and 15.97 ± 0.05 Ma (million years ago). Preceded by the Aquitanian, the Burdigalian was the first and longest war ...

stage,

Santacrucian The Santacrucian age is a period of geologic time (17.5 – 16.3 Ma) within the Early Miocene epoch of the Neogene, used more specifically with SALMA classification in South America. It follows the Colhuehuapian and precedes the Friasian age. ...

in the SALMA classification, and has a maximum thickness of .

Etymology

The formation was defined by Renz in 1960 and named after Cerro Jimol.Moreno et al., 2015, p.7

Description

Lithologies

The Jimol Formation consists of

and fossiliferous sandstones,

s and mudstones.Moreno et al., 2015, pp.18-27

Stratigraphy and depositional environment

The Jimol Formation overlies the

Uitpa Formation The Uitpa Formation ( es, Formación Uitpa, E3u) is a fossiliferous geological formation of the Cocinetas Basin in the northernmost department of La Guajira. The formation consists of calcareous mudstones interbedded with lithic sandstones. The ...

and is overlain by the Castilletes Formation. The age has been estimated to be

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene Epoch made up of two stages: the Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 Ma to 15.97 ± 0.05 Ma (million years ago). It was p ...

(17.9 to 16.7 Ma), corresponding to the

in the SALMA classification. The invertebrate fauna of the Jimol Formation is similar to the fauna found in the latest Early Miocene Cantaure Formation of Venezuela and the Culebra Formation of

Panama Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Co ...

.Moreno et al., 2015, p.23 The Jimol Formation was deposited in a beach to shallow marine environment,Rodríguez & Londoño, 2002, p.137

inner shelf Interior may refer to: Arts and media * ''Interior'' (Degas) (also known as ''The Rape''), painting by Edgar Degas * ''Interior'' (play), 1895 play by Belgian playwright Maurice Maeterlinck * ''The Interior'' (novel), by Lisa See * Interior de ...

depth (less than 50 metres'

60 ft 6 (six) is the natural number following 5 and preceding 7. It is a composite number and the smallest perfect number. In mathematics Six is the smallest positive integer which is neither a square number nor a prime number; it is the second small ...

water depth). This unit is correlated with the upper Agua Clara and lower

Cerro Pelao Formation Cerro is Spanish for "hill" or "mountain". Toponyms ;Bolivia: * Cerro Rico, the "Rich Mountain" containing silver ore near Potosi, Bolivia ;Brazil: *Cerro Branco, a municipality of Rio Grande do Sul *Cerro Grande, Rio Grande do Sul, a municipa ...

s of the Venezuelan

Falcón Basin ) , anthem = , image_map = Falcon in Venezuela.svg , map_alt = , map_caption = Location within Venezuela , pushpin_map = , pushpin_map_alt = , pushpin_mapsiz ...

.Moreno et al., 2015, p.27

Petroleum geology

The Jimol Formation is a

reservoir A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including control ...

and

seal rock A petroleum reservoir or oil and gas reservoir is a subsurface accumulation of hydrocarbons contained in porous or fractured rock formations. Such reservoirs form when kerogen (ancient plant matter) is created in surrounding rock by the presenc ...

formation in the

Guajira Basin Guajira may refer to: * Guajira Peninsula, a peninsula in the northernmost part of South America shared by Colombia and Venezuela * Guajiro people (Wayuu), a South American ethnic group inhabiting northeastern Colombia and northwestern Venezuela * ...

.ANH, 2010

Fossil content

References

Bibliography

Local geology

* * *

Paleontology

* *

Maps

* * * * {{Paleontology in Colombia, state=collapsed Geologic formations of Colombia Neogene Colombia Miocene Series of South America Burdigalian Santacrucian Sandstone formations Siltstone formations Mudstone formations Beach deposits Shallow marine deposits Reservoir rock formations Seal rock formations Fossiliferous stratigraphic units of South America Paleontology in Colombia Geography of La Guajira Department