Earth:Chilean Iron Belt

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Chilean Iron Belt
Stratigraphic range: Cretaceous
~132–84 Ma
TypeMining district
Location
Coordinates [ ⚑ ] : 27°21′59″S 70°25′59″W / 27.366389°S 70.433056°W / -27.366389; -70.433056
RegionAtacama Region, Coquimbo Region
CountryChile
ExtentAtacama Fault System
Chilean Iron Belt is located in Chile
El Carmen
El Carmen
Los Colorados
Los Colorados
El Romeral
El Romeral
Chilean Iron Belt (Chile)

The Chilean Iron Belt is a geological province rich in iron ore deposits in northern Chile. It extends as a north-south beld along the western part of the Chilean regions of Coquimbo and Atacama, chiefly between the cities of La Serena and Taltal.[1][2] The belt follows much of the Atacama Fault System and is about 600 km long and 25 km broad.[2][3]

Iron oxide-apatite, iron oxide copper gold ore deposits (IOCG) and manto-type copper and silver are the main types of deposits.[1][2] Iron-apatite and IOCG are considered to have different origins.[4] Manto-type deposits are concentrated in the northern part of the belt and are chiefly emplaced on rocks of La Negra Formation.[1]

The ores of the Chilean Iron Belt formed in separate pulses in the Cretaceous period as result of magmatic and hydrothermal processes.[1] At least part of the iron oxide-apatite rock originated from molten iron in the form of lava, tephra.[3] and intrusions.[4] Thus iron oxide apatite magma cooled into rock variously from surface volcanoes to depths of 10 km over even more.[4]

Some geologists have speculated that a large meteorite impact in the Pacific during the Cretaceous period may have set in motion a series of tectonic changes that led to the formation the ores.[5]

Iron mines along the Chilean Iron Belt

  • El Carmen
  • Los Colorados
  • El Algarrobo
  • El Tofo (defunct)
  • El Romeral

References

  1. 1.0 1.1 1.2 1.3 Barra, Fernando; Reich, M.; Selby, D.; Rojas, P.; Simon, A.; Salazar, E.; Palma, G. (2017). "Unraveling the origin of the Andean IOCG clan: a Re-Os isotope approach". Ore Geology Reviews 81 (1): 62–78. doi:10.1016/j.oregeorev.2016.10.016. Bibcode2017OGRv...81...62B. https://dro.dur.ac.uk/20115/1/20115.pdf. 
  2. 2.0 2.1 2.2 Simon, Adam C.; Knipping, Jaayne; Reich, Martin; Barra, Fernando; Deditius, Artur P.; Bilenker, Laura; Childress, Tristan (2018). "Kiruna-Type Iron Oxide-Apatite (IOA) and Iron Oxide Copper-Gold (IOCG) Deposits Form by a Combination of Igneous and Magmatic-Hydrothermal Processes: Evidence from the Chilean Iron Belt". in Arribas R., Antonio M.. Metals, Minerals, and Society. Society of Economic Geologists Special Publication. 21. pp. 89–114. doi:10.5382/SP.21. ISBN 9781629493084. 
  3. 3.0 3.1 Travisany, Vinicio; Henríquez, Fernando; Nyström, Jan Olov (1995). "Magnetite lava flows in the Pleito-Melon District of the Chilean iron belt". Economic Geology 90 (2): 438–444. doi:10.2113/gsecongeo.90.2.438. Bibcode1995EcGeo..90..438T. 
  4. 4.0 4.1 4.2 Tornos, Fernando; Hanchar, John M.; Munizaga, Rodrigo; Velasco, Francisco; Galindo, Carmen (2020). "The role of the subducting slab and melt crystallization in the formation of magnetite-(apatite) systems, Coastal Cordillera of Chile". Mineralium Deposita 56 (2): 253–278. doi:10.1007/s00126-020-00959-9. 
  5. Oyarzún, J.; Oyarzun, R.; Lillo, J.; Ménard, J.J. (2012). "May a large asteroid impact in the Pacific have triggered a cascade of tectonomagmatic events leading to formation of the Mid-Cretaceous Chilean Iron Belt?". Geotemas 13: 1915–1918. https://dialnet.unirioja.es/servlet/articulo?codigo=8214048.