Wednesday, August 1, 2012

Andean Anthropogenic Alluvial Fans

[the mining spoils dump site to the west of the Chiquicamata Mine outside of Calama, Chile in the Atacama desert forms a sort of alluvial fan working towards the Andean cordillera; this anthropogenic deltaic fan is also fundamentally shaped and formed by water, as well as Catepillar trucks and Cenezoic Era geology]

Copper has been mined at the Chiquicamata Copper Mine since at least 550 CE. Industrial scale operations began on the site in 1910, only 30 years after Chile had wrested control of the area away from the Bolivians at the behest of British agricultural interests (among other things). To date it has produced some 29,000,000 metric tons of pure copper, leaving a hole in the Atacama that is nearly 900 meters deep and creating a complex nearly 5 kilometers wide. As the mine has expanded, it's pits and waste dumps have covered old mining camps and evacuated formerly thriving towns.

None of this would be possible without the aqueduct that was constructed to bring water 55 miles over the Andes to the site in order to enable the Guggehnheim Process perfected in Utah by Elias Smith. This process is a method of chemical precipitation that prepares sludge for filtration. However, to get sludge you need water, and to get water in the middle of the Atacama, you have to build a 55 mile aqueduct bringing water up over the Andes and down to Calama, which the Guggenheims paid some people to do. In this way, the great alluvial fan of the Chiquicamata Mine is a natural history of one hundred years of open-pit industrial operations.

According to Mining Technology there is currently a project to shift these operations to below ground mining tunnels. With this shift the mine is projected to remain operational until 2060. At that same time a new project was announced to bring some 6,000 cubic liters of water every hour to the Chiquicamata and Escondida Copper mines from the aquifer below Salta, Argentina. This new influx of extra-basin water, limited to 170,400,000 cubic meters per year, combined with a radical shift in mining operations are sure to produce their own mophologies and natural histories. New delta landscapes of the Atacama Desert.

[the Chiquicamata Mine from above; in this aerial south is up; the different morphologies can be read as a natural history of a massive interbasin water transfer, Cenezoic copper deposits, and the movement of diesel shovels and dump trucks]

2 comments:

  1. man made deltas in the middle of a desert amazing....

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  2. That is both beautiful and frightening. Is there any information about the compostion of the mine tailings? I suspect that they are full of heavy metals and other harmful constituents. I wonder what happens over 1,000,000 years when these spoils are re-incorporated into the geologic strata of the region?

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