| Venezuelan Andes | |
|---|---|
| Andes venezolanos | |
.jpg) A view of Collado of Condor Peak in Venezuelan Andes | |
| Highest point | |
| Coordinates | 8°45′N70°55′W / 8.750°N 70.917°W /8.750; -70.917 |
| Geography | |
 Geographic map of the Andean Venezuelan natural region. | |
| Location | Táchira,Mérida andTrujillo states, the southern area ofLara, and portions of higher areas on the western side ofBarinas,Apure,Portuguesa andZulia states |
| Parent range | Andes |
| Geology | |
| Rock age | Eocene |
| Rock type(s) | Igneous and metamorphic rocks |
TheVenezuelan Andes (Spanish:Andes Venezolanos) also simply known asthe Andes (Spanish:Los Andes) in Venezuela, are amountain system that form the northernmost extension of theAndes. They are fully identified, both by their geological origin as by the components of the relief, the constituent rocks and the geological structure.
The Venezuelan Andean system represents the terminal bifurcation of theCordillera Oriental de Colombia, which in Venezuelan territory consists of two mountainous branches: theSierra de Perijá, smaller, slightly displaced from southwest to northeast with 7,500 km2 in Venezuela; and a larger, frankly oriented Southwest to northeast with about 40,000 km2, theCordillera de Mérida, commonly known as the proper Venezuelan Andes.[1] The highest point inVenezuela is located in this natural region.[2] It covers around 5.2% of the national territory, being the 4th largest natural region in Venezuela.
Venezuelan Andes can be divided in two sections:
They have a common geological origin, which dates back to theEocene period of the earlyTertiary era, about 40-50 million years ago, coincides with the beginning of the contact of the threetectonic plates (Nazca,Caribbean andSouth American) that began their orographic rise.
Before the rise of the current Venezuelan Andes, between theCambrian andSilurian periods, the so-calledprimitive Andes emerged, which already for theTriassic period (Mesozoic era) had been almost completely flattened because of the intense erosive process to which were subjected.[4]
It's characterized by the interaction of the three most important lithospheric plates in the region:Nazca,Caribbean andSouth American. A northwest-southwest oriented direction of compression produces vertical and horizontal deformation components, with the formation of thrusts align the Andean borders, andstrike-slip faults. The split of Venezuelan Andes apparently began in the Late Eocene, and its present height was probably attained before the Quaternary.
During theQuaternary. the main active structures are the strike-slip faults. the principal one being theBoconó Fault Zone, with a measured dextral displacement of several millimeters per year. In the field this displacement is shown by the existence offault trenches,fault depressions,sag ponds,offset ridges andlateral moraines.[5]
Like all tropical mountain ranges with altitudes above 3,000 m, the Venezuelan Andes were affected byPleistocene glaciations.
Two morainic complexes have been recognized in theCordillera de Mérida: one between 2,600 and 2,800 m altitude, and another one between 2,900 and 3,500 m. These two levels have been considered as Early and Late Stades, respectively, of theMérida glaciation. The moraines of the Late Stade are topographically well represented, and several superposed moraines, or morainic complexes, are found. The glaciated area in Cordillera de Mérida during theLast Glacial Maximum was approximately 600 km2[6][7][8][9]
In theSierra de Perijá, the existence of moraines has been mentioned at altitudes between 2,700 and 3,100 m. In the absence of more detailed data, these have been tentatively assigned to the Late Stade of the Mérida glaciation.[10]
Evidence of Late Holocene morainic sedimentation are based on palynological and radiocarbon analyses, which established a cold phase between the 15th and middle-19th centuries, which can be correlate with theLittle Ice Age. The moraines associated with this phase are most probably those located at an altitude of approximately 4,700 m between 100 and 200 below the terminal zone of present-day glaciers.[11]
.jpg)
{{cite journal}}: CS1 maint: multiple names: authors list (link).png)