What are the metallogenic belts? How many have been identified in Argentina?
Metalogenesis is the study of the genesis (origin) of mineral deposits in the earth’s crust, defining their location in time and space within the geological context.
Geological events that occurred at specific times and in specific areas of the earth’s crust conditioned the formation of mineral deposits. By studying and associating environments to each type of mineral deposit, we can infer what types of deposits there may be from the geological characteristics that the area has.
With this geological history, it is possible to make “favorability maps” in which the areas with the greatest probability of finding minerals are revealed. The spatial, temporal and geological distribution of known mineral deposits has led to the definition of models for potential deposits linked to a particular geo-tectonic environment.
Based on this, prospective areas with potential to discover the defined deposit types can be identified. These common features which group mineral deposits are called metallogenic province, which in turn can be subdivided into metallogenic belts.
According to the Argentine Geological Service (SEGEMAR), nine metallogenic belts are recognized in Argentina as favourable for mineral exploration and exploitation. These belts are associated with the country’s geological activity and the presence of various types of mineral deposits. The main belts are:
- Metallogenic Andean Band: It extends along the Andes and is rich in metals such as copper, gold, silver, molybdenum and zinc. This band is associated with large porphyry and epitermal deposits.
- Metallogenic Belt of Epitermal and Subepitermal Gold: It is found mainly in the Argentine northwest and is associated with the formation of gold and silver in deposits of type epitermal and mesothermal.
- Metallogenic Belt of the Copper Porphyry Belt: Located in the west of the country, along the Andes Cordillera. It is one of the main copper producing bands, related to the copper porphyry type deposits.
- Uranium Metallogenic Belt: Located in the south-central region of the country, this belt is key to uranium mining, particularly in the provinces of Mendoza, La Rioja, Chubut and San Juan.
- Metallogenic Belt of the Sierra Pampeana: It extends through the northwest and center of the country, and contains metals such as lead, zinc, silver and tin, in hydrothermal deposits and vetiformes.
- Patagonian Metallogenic Belt: Located in Patagonia, with deposits of gold, silver, copper, and industrial minerals. It is found in the provinces of Chubut and Santa Cruz, and is associated with low-sulphidation epithermal deposits.
- Metallogenic Belt of the Somuncurá Plateau: It is located in Patagonia and is linked to deposits of industrial minerals such as gypsum, bentonite and barytin.
- Metallogenic Belt of the Subandean Mountains: In the Argentine northwest, with deposits of zinc, lead, silver and manganese in stratolinked deposits.
- Metallogenic Belt of the Precordillera and Cuyo: Covers part of Mendoza and San Juan, and is associated with deposits of copper, silver, gold and lead. This belt is linked to stratospheric deposits of hydrothermal origin.
These bands represent the most promising areas for metal exploration in Argentina, and are related to the country’s complex geological history.
How many of these belts were recognized in Mendoza?
Mendoza is crossed by 5 of the main metallogenic belts. Studies by the SEGEMAR confirm that the province has in its soil and subsoil critical materials for energy transition, such as copper, cobalt and uranium; plants for industry, such as iron; for technology, such as gold and silver; or for food safety, such as potassium.
The most promising bands, with respect to copper potential, are projected from Chile and have continuity in Mendoza, and enter the south of the province in the department of Malargüe.
They include the giant deposits of El Teniente and the Río Blanco-Los Bronces cluster; located immediately west of the Mendoza range and close to the international boundary.
There are also other areas with high geological potential for exploration in the rest of the province, related to copper porphyries, epitermal and polymetallic deposits, sedimentary deposits of copper, uranium and vanadium and also evaporitic (potassium) type deposits.
The existing and unexploited mining potential in the province of Mendoza is used to estimate its economic potential, whose value can be approximated by referencing the levels of activity and productive value of the mines of Chile and San Juan, with which we share the Cordillera.
