The geology of Venezuela It is very varied and has the oldest formations on the planet. High mountains can be found in the west, coasts in the north, plains in the center, jungles and savannahs in the south, and huge massifs in the southeastern zone.
Venezuela is located in the north of South America, just above the land Ecuador.
Geological description of the Venezuelan territory
To the west of the territory of Venezuela is located the Sierra de Perijá, next to the Maracaibo basin (Lake Maracaibo and lowlands).
To the east of this basin is a more mountainous region, in the Falcón state, with an extremity that ends in a flat peninsula called Paraguaná.
The Venezuelan Andes are located to the west and extend east to touch the Cordillera de la Costa, which borders the north of the country.
With the Andean mountain range as the beginning, large plains extend to the south, where the highlands of Guayana burst. It is believed that at this point Venezuela joined the African continent.
To the northeast there is a low and marshy area, in the Delta Amacuro state.
The 4 geological eras that Venezuela has lived
1- It was Precambrian
During the Lower Paleozoic the development of a geosyncline began in what is now the lower basin of the Amazon River.
This gave rise to the fact that the original mass separates into two parts: one that went south, the Brazilian shield; and another, which faces north, the Guiana shield.
It is from the Guiana shield from where a fifth of Venezuela is born. The rock formations of this shield were under the sea more than 3,500 million years ago.
At that time there were movements and submarine volcanic eruptions that altered the original rocks and gave rise to the sediments of Roraima. Since then, it is a formation that rises above sea level.
2- It was Paleozoic
This era begins with the north of South America above sea level, but soon the sea covered several areas that were eroded.
And it continued to do so in the next 250 million years, covering what are now the Táchira, Trujillo and Mérida states, and what is now Lake Maracaibo. Merida was a kind of island.
This"maritime invasion"reached Perijá, where swamps were formed. This era ended with the Hercynian orogenesis, which violently deformed western Venezuela.
3- Mesozoic Era
The Mesozoic was the era in which the fracture of the Venezuelan Guiana Shield occurred, which was out of the sea. This fracture did not reach the surface. Wide folds formed with gentle slopes on their flanks.
Then a mountain chain that extends from south to north from the current state Barinas, to Lake Maracaibo. Its depressions eroded during the 100 million years of the Triassic and Jurassic.
4- Cenozoic era
In the Cenozoic era, Venezuelan biodiversity is configured. The vast majority of plant and animal species that are known today appear.
It is known that some species also disappeared such as rudists, belemnites, ammonites, flying and marine reptiles.
The 10 main geological formations of Venezuela
1- The Callao
It is a formation of about 3 thousand meters thick consisting of volcanic lavas of coarse and fine grain. It is located on the Yuruari River, near el Callao, in the south of the country.
It is an economically important formation for Venezuela for covering veins of gold quartz and reef.
2- Cicapra
It is located in the Cicapra ravine, which is one of the tributaries of the Yuruari River. It has an estimated thickness of 2000 meters.
3- Formation Caparo
It is named after the Caparo River, located in the state of Merida. It is a sequence of rocks with a thickness of approximately 200 meters.
It is formed by sandstone and micaceous litomites, fine and coarse-grained sandstones, calcareous sandstones and fossiliferous shales.
4- Yuruari
It is located on the Yuruari River near the village Pastora, and is a sedimentary sequence formed in shallow waters with an approximate thickness of 5 thousand meters.
Its rocks are constituted by volcanic fragments, grauvacas, schists and tobaceous breccias.
5- Caballape
This formation constitutes a discordant sequence located in the Dividual ravine, affluent of the Caballape river.
It is made up of conglomeratic sediments, volcanic fragments and tuffs. Its thickness ranges between 5000 and 8000 meters.
6- Bella Vista
It is a Precambrian lithological sequence located in the Andean zone of Venezuela, without fossils. It is composed of sericitic, chloritic and graffitic shales.
7- Roraima
It is an almost horizontal sedimentation sequence, located in the Cerro de Roraima and other regions of the Bolívar and Amazonas states.
It has an approximate thickness of 2600 meters and is constituted by shales, conglomerates, feldspathic quartz, sandstone, jasper and ascetic.
8- Mucuchachí
It is a stratigraphic sequence located in the current Merida state that contains fossils. It is made up mainly of silty shales.
9- Sabaneta
It is another of the formations located in the state of Merida. It has coarse and fine grain sandstones, with vegetable fossils. It also contains limestones and shales.
10- The Fifth
A formation located near La Grita, state Táchira, which was formed between the Upper Triassic and the Lower Jurassic.
Its thickness is estimated at 2400 meters and was formed with conglomerate and clayey sandstones, shales and red conglomerates.
Venezuelan geology and landscapes
The geological history of Venezuela originated markedly different landscapes in a relatively small area of land.
For example, the following landscapes can be mentioned:
- Tepuyes de Canaima.
- Dunes of the Médanos de Coro.
- Cave of sedimentary rocks of El Guácharo.
- The Sierra Nevada.
- Archipelago, islets, cays and islands.
Economic importance
The geological formations that occurred in this South American country have had consequences in the national economy because they have made possible a tourist development and the exploitation of oil.
Although the tourism industry does not represent a very important contribution to Venezuela's GDP (-4.7% in 2016), it does constitute an important potential for attracting foreign capital and promoting national development.
The territory that was between Guiana in the south east and the Sierra de Perijá and the Cordillera de los Andes in the west, became one of the most important oil deposits in the world.
This oil is currently the main export product of Venezuelans.
References
- Digital Caraota (2017). Venezuela is the country with the lowest contribution of tourism to GDP in the world. Retrieved from: caraotadigital.net
- Venezuelan Geology (2011). The 7 geological wonders of Venezuela. Retrieved from: geologiavenezolana.blogspot.com
- Venezuelan Geology (2012) The Cenozoic in Venezuela. Retrieved from: geologiavenezolana.blogspot.com
- Oil of America (2010). Geology of Venezuela and terms. Retrieved from: petroleoamerica.com
- Urbani, Franco (2011). An outline of the geology of Venezuela. BioLlania Special Edition.
- Venaventours (s / f). Relief and geology of Venezuela. Retrieved from: venaventours.com