The Hiló Formation (, Kih) is a

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

Altiplano Cundiboyacense The Altiplano Cundiboyacense () is a high plateau located in the Eastern Cordillera of the Colombian Andes covering parts of the departments of Cundinamarca and Boyacá. (Do not confuse with The Altiplano or the Altiplano Nariñense, both fur ...

Eastern Ranges The Eastern Ranges is an Australian rules football team that currently competes in the Talent League, the Victorian statewide under-18s competition. History Inaugural playing squad (1992) Honours *Premiers (2): 2002, 2013 *Runners-up (6): 199 ...

of the

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 ...

Andes The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...

. The predominantly

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of Clay mineral, clay minerals (hydrous aluminium phyllosilicates, e.g., Kaolinite, kaolin, aluminium, Al2Silicon, Si2Oxygen, O5(hydroxide, OH)4) and tiny f ...

formation dates to the

Middle Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 77.1 million years, it is the ninth and longest geologi ...

period; Late Albian to Early Cenomanian epochs and has a measured thickness at its type section of . The fossiliferous formation has provided a great abundance of

ammonite Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family N ...

s and other marine species.

Etymology

The formation was defined and named in 1931 by Hubach after the Caserío Boquerón de Hiló in Anapoima.Acosta & Ulloa, 2002, p.44

Description

Lithologies

The Hiló Formation with a measured thickness of , is characterised by a sequence of pyritic

organic shale Organic may refer to: * Organic, of or relating to an organism, a living entity * Organic, of or relating to an anatomical organ Chemistry * Organic matter, matter that has come from a once-living organism, is capable of decay or is the product o ...

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 and

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, with

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 ...

banks intercalated in the formation.

Stratigraphy and depositional environment

The Hiló Formation overlies the Capotes Formation and is overlain by the

Simijaca Formation The Simijaca Formation (, K2S, Kss) is a formation (geology), geological formation of the Altiplano Cundiboyacense, Cordillera Oriental (Colombia), Eastern Ranges of the Colombian Andes. The predominantly mudstone formation dates to the Late Cretac ...

. The age has been estimated to be Late Albian to Early Cenomanian. Stratigraphically, the formation is time equivalent with the Une and Pacho Formations.Acosta & Ulloa, 2001, p.16 The formation has been deposited in an

open Open or OPEN may refer to: Music * Open (band), Australian pop/rock band * The Open (band), English indie rock band * ''Open'' (Blues Image album), 1969 * ''Open'' (Gerd Dudek, Buschi Niebergall, and Edward Vesala album), 1979 * ''Open'' (Go ...

platform setting. The deposition is represented by a

maximum flooding surface In sequence stratigraphy, a maximum flooding surface is the surface that marks the transition from a transgression to a regression. Maximum flooding surfaces are abbreviated by mfs, synonyms for them include final transgressive surface, surface of ...

and pelagic to hemipelagic conditions.Villamil, 2012, p.164

Fossil content

Fossils of '' Actinoceramus munsoni'', '' Actinoceramus aff. subsulcatiformis'', '' Beudanticeras cf. rebouli'', '' Desmoceras latidorsatum'', '' Eubrancoceras cf. aegoceratoides'', '' Exogyra aff. texana'', '' Goodhallites aguilerae'', '' Inoceramus anglicus'', '' Inoceramus cf. cadottensis'', '' Inoceramus aff. dunveganensis'', '' Inoceramus aff. etheridgei'', '' Inoceramus cf. ewaldi'', '' Inoceramus aff. irenensis'', '' Inoceramus prefragilis'', '' Inoceramus cf. richensis'', '' Lyelliceras pseudolyelli'', '' Mojsisovicsia evansi'', '' Mortoniceras arietiforme'', '' Neocomiceramus neocomiensis'', '' Neoharpoceras hugardianum'', '' Oxytropidoceras intermedium'', '' Oxytropidoceras karsteni'', '' Oxytropidoceras laraense'', '' Oxytropidoceras multicostatum'', '' Oxytropidoceras nodosum'', '' Oxytropidoceras peruvianum'', '' ?Oxytropidoceras robustum'', '' Oxytropidoceras venezolanum'', '' Prolyelliceras gevreyi'', '' Prolyelliceras prorsocurvatum'', '' Puzio media'', '' Tegoceras mosense'', '' Acompsoceras sp.'', '' ?Bositra sp.'', '' Camptonectes sp.'', '' Entolium sp.'', '' Hamites sp.'', '' Hysteroceras sp.'', '' Mariella sp.'', '' Ostrea sp.'', '' Phelopteria sp.'', and '' ?Syncyclonema sp.'' have been found in the Hiló Formation.Olini Creek 1
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Fossilworks Fossilworks was a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world. History Fossilworks was cr ...

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Outcrops

The Hiló Formation is apart from its type locality along the road from Apulo to Anapoima, found just east of Viotá, Cundinamarca,Plancha 246, 1998 and in the department of Tolima. West of Guayabal de Síquima, the formation is offset by the Vianí Fault.Plancha 227, 1998

References

Bibliography

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Maps

* * * {{DEFAULTSORT:Hilo Formation Geologic formations of Colombia Cretaceous Colombia Lower Cretaceous Series of South America Upper Cretaceous Series of South America Albian Stage Cenomanian Stage Shale formations Open marine deposits Fossiliferous stratigraphic units of South America Paleontology in Colombia Formations Formations Formations