The Bogotá Fault () is a major inactive slightly dextral oblique

thrust fault A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. I ...

in the department of Cundinamarca in central

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 fault has a total length of , while other authors designate a length of , and runs along an average north-northeast to south-southwest

strike Strike may refer to: People *Strike (surname) * Hobart Huson, author of several drug related books Physical confrontation or removal *Strike (attack), attack with an inanimate object or a part of the human body intended to cause harm * Airstrike, ...

of 013.5 ± 7 across 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 ...

, central part of the

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 Colombian

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 fault stretches from the Gallo River at the

Sumapaz Páramo Sumapaz Páramo (Spanish: ''Páramo de Sumapaz'' - meaning "Utterly peaceful moorland" ) is a large páramo ecosystem located in the Altiplano Cundiboyacense mountain range, considered the largest páramo ecosystem in the world. It was decla ...

in the south to the Teusacá River in the north and borders the

Bogotá savanna The Bogotá savanna is a savanna#Savanna ecoregions, montane savanna, located in the southwestern part of the Altiplano Cundiboyacense in the center of Colombia. The Bogotá savanna has an extent of and an average altitude of . The savanna is si ...

and the Colombian capital to the east. The Bogotá Fault formed the pronounced Eastern Hills, with the well-known Monserrate and Guadalupe Hills, east of the Colombian capital. The brecciated fault zone is exposed along the road from Bogotá to La Calera and a vertical displacement of at least has been determined. The

hanging wall In geology, a fault is a Fracture (geology), planar fracture or discontinuity in a volume of Rock (geology), rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust (geology ...

of the reverse fault contains the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

Chipaque Formation The Chipaque Formation (, K2cp, Kc) is a geological formation of the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The formation is also described as Gachetá Formation, named after Gachetá, in the area of the Llanos foothills ...

and Guadalupe Group and the

footwall In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic f ...

consists of the

Paleogene The Paleogene Period ( ; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period Ma (million years ago) to the beginning of the Neogene Period Ma. It is the fir ...

and

Neogene The Neogene ( ,) 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 million years ago. It is the second period of th ...

Guaduas Guaduas () is a municipality and town in Colombia, in the Lower Magdalena Province department of Cundinamarca Department, Cundinamarca, about 117 km from Bogotá. It is an agricultural and tourist center of some importance with a populati ...

, Cacho and

Bogotá Formation The Bogotá Formation (, E1-2b, Tpb, Pgb) is a geological formation of the Eastern Hills and Bogotá savanna on the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The predominantly shale and siltstone formation, with sandstone ...

s. Pulsations of the fault movement in the early

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the ...

have produced the

alluvial fan An alluvial fan is an accumulation of sediments that fans outwards from a concentrated source of sediments, such as a narrow canyon emerging from an escarpment. They are characteristic of mountainous terrain in arid to Semi-arid climate, semiar ...

s of the Tunjuelo Formation. In part, the fault is covered by Late

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

deposits of the Sabana Formation showing a pre-Holocene activity with no known historical seismicity or registered damages. The present slip rate of the Bogotá Fault is established at per year.

Etymology

The fault is named after

Bogotá Bogotá (, also , , ), officially Bogotá, Distrito Capital, abbreviated Bogotá, D.C., and formerly known as Santa Fe de Bogotá (; ) during the Spanish Imperial period and between 1991 and 2000, is the capital city, capital and largest city ...

, Cundinamarca by Thomas Clements, who performed the first study on the fault in 1940.

Description

The Bogotá Fault extends across the

along the base of the mountain front that borders the flatlands known as the

, to the east bordering the Bogotá Anticlinal for .Lobo-Guerrero Uscátegui, 2005, p.4 The fault follows the longitudinal axis of the Eastern Hills, striking north-northeast to south-southwest at 013.5 ± 7 and dipping 15-25 degrees to the east.Lobo-Guerrero Uscátegui, 2005, p.1 It forms the tectonic limit with the Bogotá savanna and acts as a barrier for

aquifer An aquifer is an underground layer of water-bearing material, consisting of permeability (Earth sciences), permeable or fractured rock, or of unconsolidated materials (gravel, sand, or silt). Aquifers vary greatly in their characteristics. The s ...

s.Velandia & De Bermoudes, 2002, p.42 The fault runs parallel to the

Usme Fault The Usme Fault () is a dextral strike-slip fault, oblique normal fault in the departments of Colombia, department of Cundinamarca Department, Cundinamarca in central Colombia. The fault has a total length of and runs along an average north-northe ...

.Paris et al., 2000b The tectonic regime of the

and

is the result of the interaction of four

tectonic plates Plate tectonics (, ) is the scientific theory that the Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of , an idea developed durin ...

; the Malpelo Plate in the west, the Caribbean Plate in the north, the

South American Plate The South American plate is a major tectonic plate which includes the continent of South America as well as a sizable region of the Atlantic Ocean seabed extending eastward to the African plate, with which it forms the southern part of the Mid ...

in the east and the North Andes Plate where the Altiplano Cundiboyacense is located. The compressional tectonics of the

Andean orogeny The Andean orogeny () is an ongoing process of orogeny that began in the Early Jurassic and is responsible for the rise of the Andes mountains. The orogeny is driven by a reactivation of a long-lived subduction system along the western margin o ...

thrusted the Cretaceous units of the Guadalupe Group and

on top of the younger

, Cacho and

s.Geological Map Bogotá, 1997 The timing of the recent Andean uplift was Pleistocene, concluded on the basis of

apatite Apatite is a group of phosphate minerals, usually hydroxyapatite, fluorapatite and chlorapatite, with high concentrations of Hydroxide, OH−, Fluoride, F− and Chloride, Cl− ion, respectively, in the crystal. The formula of the admixture of ...

fission track analysis by structural geologist Andrés Mora.Torres et al., 2005, p.131 The

units of the

are folded producing the Bogotá Anticlinal,Lobo-Guerrero Uscátegui, 2005, pp.13–14 and showing a vertical stratigraphic displacement of at least .Lobo-Guerrero Uscátegui, 1992, p.8 The Sabana Formation, named after the Bogotá savanna were deposited in the Pleistocene

paleolake A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from t ...

Lake Humboldt, of which the many

wetlands A wetland is a distinct semi-aquatic ecosystem whose groundcovers are flooded or saturated in water, either permanently, for years or decades, or only seasonally. Flooding results in oxygen-poor ( anoxic) processes taking place, especially ...

and the

Bogotá River The Bogotá River is a major river of the Cundinamarca Department, Cundinamarca department of Colombia. A right tributary of the Magdalena River, the Bogotá River crosses the region from the northeast to the southwest and passing along the wester ...

are the present-day remainders.Montoya & Reyes, 2005, p.72 The fault mainly cuts

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

and

Tertiary Tertiary (from Latin, meaning 'third' or 'of the third degree/order..') may refer to: * Tertiary period, an obsolete geologic period spanning from 66 to 2.6 million years ago * Tertiary (chemistry), a term describing bonding patterns in organic ch ...

sedimentary rocks and, to some extent, early

deposits. The fault produces strong slope changes between different geologic units on both sides of the fault plane and displays degraded fault scarps,Paris et al., 2000a, p.47 especially the well-known Monserrate, the location where the fault was first studied.Lobo-Guerrero Uscátegui, 2005, p.2 The

breccia Breccia ( , ; ) is a rock composed of large angular broken fragments of minerals or Rock (geology), rocks cementation (geology), cemented together by a fine-grained matrix (geology), matrix. The word has its origins in the Italian language ...

ted zone of the fault has a width between . The brecciated area of the fault is well exposed along the road from Bogotá to La Calera, north of Calle 85 in the capital. At the entrance to the cable car going up to Monserrate, the fault shows reverse and normal offset faults and produced fractures in the

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 ...

s (Plaeners Formation) of the Guadalupe Group. The

s of the Tunjuelo Formation were produced by the seismic pulses of the Bogotá Fault.Lobo-Guerrero Uscátegui, 1996, p.13

Activity

The Bogotá Fault was first analyzed by Thomas Clements in 1940,Clements, 1940 and he concluded the fault was still active.Lobo-Guerrero Uscátegui, 2005, p.5 However, later studies have shown the fault does not displace younger Quaternary deposits and is hence determined being inactive. No known historical earthquakes have been produced by the fault,Espinosa Baquero, 2004 and recent seismic activity has not been registered.Acosta & Garay, 2002, p.93 The Bogotá Fault crosscuts the Rosales tunnel where no damages have been noted.Lobo-Guerrero Uscátegui, 2005, p.6 A slip rate of per year is calculated from displaced geomorphologic Quaternary features.Paris et al., 2000a, p.48

Gallery

File:Monserrate.JPG, Monserrate Hill was formed by the Bogotá Fault File:Cerro Aguanoso Bogota.JPG, Fault scarps at Cerro Aguanoso File:Chapinero, Bogotá, Bogota, Colombia - panoramio - aalozadag (8).jpg, Intense fracturing in the Guadalupe Group

References

Bibliography

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Maps

* * * * * {{DEFAULTSORT:Bogota Fault Seismic faults of Colombia Thrust faults Inactive faults Faults Faults Geography of Bogotá