Casquet, César and Galindo Francisco, Mª del Carmen and Tornos Arroyo, Fernando and Velasco Roldán, Francisco and Canales Gallarosa, Ángel (2001) The Aguablanca Cu–Ni ore deposit (Extremadura, Spain), a case of synorogenic orthomagmatic mineralization: age and isotope composition of magmas (Sr, Nd) and ore (S). Ore geology reviews, 18 . pp. 237-250. ISSN 0169-1368
Official URL: http://www.elsevier.com/locate/oregeorev
The Aguablanca Cu–Ni orthomagmatic ore deposit is hosted by mafic and ultramafic rocks of the Aguablanca stock, which is part of the larger, high-K calc-alkaline Santa Olalla plutonic complex. This intrusive complex, ca. 338 Ma in age, is located in the Ossa-Morena Zone (OMZ) of the Iberian Variscan Belt. Mineralization consists mainly of pyrrhotite, pentlandite and chalcopyrite resulting from the crystallization of an immiscible sulphide-rich liquid. Isotope work on the host igneous rocks (Sr, Nd) and the ore (S) suggests that contamination with an upper-crustal component took place at some depth before final emplacement of the plutons (εNd338= -6 to -7.5; Sr(338)=0.7082 to 0.7100; δ34(sulphides) near + 7.4‰). Assimilation–fractional crystallization (AFC) processes are invoked to explain early cumulates and immiscible sulphide-magma formation. Intrusion took place at the beginning of the type-A oblique subduction of the South Portuguese Zone under the Ossa-Morena Zone and was probably driven by transpressive structures (strike-slip faults). The mineralization is thus synorogenic. Aguablanca is probably the first case referred to in the literature of a magmatic Cu–Ni ore deposit hosted by calc-alkaline igneous rocks.
|Uncontrolled Keywords:||Cu–Ni ores; Calc-alkaline magmatism; Isotope geochemistry; Variscan orogeny; Spain|
|Subjects:||Sciences > Geology > Petrology|
|Deposited On:||02 Feb 2011 14:09|
|Last Modified:||02 Feb 2011 14:09|
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