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Why large porphyry Cu deposits like high Sr/Y magmas?

ABSTRACT: Porphyry systems supply most copper and significant gold to our economy. Recent studies indicate that they are frequently associated with high Sr/Y magmatic rocks, but the meaning of this association remains elusive. Understanding the association between high Sr/Y magmatic rocks and porphyry-type deposits is essential to develop genetic models that can be used for exploration purposes. Here we present results on a Pleistocene volcano of Ecuador that highlight the behaviour of copper in magmas with variable (but generally high) Sr/Y values. We provide indirect evidence for Cu partitioning into a fluid phase exsolved at depths of ~15?km from high Sr/Y (>70) andesitic magmas before sulphide saturation. This lends support to the hypothesis that large amounts of Cu- and S-bearing fluids can be accumulated into and released from a long-lived high Sr/Y deep andesitic reservoir to a shallower magmatic-hydrothermal system with the potential of generating large porphyry-type deposits.

SUBMITTER: Chiaradia M

PROVIDER: S-EPMC3449286 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Why large porphyry Cu deposits like high Sr/Y magmas?

Chiaradia Massimo M Ulianov Alexey A Kouzmanov Kalin K Beate Bernardo B

Scientific reports 20120924

Porphyry systems supply most copper and significant gold to our economy. Recent studies indicate that they are frequently associated with high Sr/Y magmatic rocks, but the meaning of this association remains elusive. Understanding the association between high Sr/Y magmatic rocks and porphyry-type deposits is essential to develop genetic models that can be used for exploration purposes. Here we present results on a Pleistocene volcano of Ecuador that highlight the behaviour of copper in magmas wi ...[more]

PMID: 23008750

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