Abstract. We investigate the occurrence and chemistry of magmatic
sulfides and their chalcophile metal cargo behaviour during the evolution of
compositionally different magmas from diverse geodynamic settings both in
mineralised and barren systems. The investigated areas are the following: (a) the Miocene
Konya magmatic province (hosting the Doğanbey Cu–Mo porphyry and Inlice
Au epithermal deposits, representing post-subduction) and (b) the Miocene Usak basin
(Elmadag, Itecektepe, and Beydagi volcanoes, the latter associated with the
Kişladağ Au porphyry in western Turkey, representing post-subduction). For comparison we
also investigate (c) the barren intraplate Plio-Quaternary Kula volcanic
field west of Usak. Finally, we discuss and compare all the above areas
with the already studied (d) Quaternary Ecuadorian volcanic arc (host to the
Miocene Llurimagua Cu–Mo and Cascabel Cu–Au porphyry deposits, representing subduction).
The volcanism of the newly studied areas ranges from basalts to
andesites–dacites and from high-K calc-alkaline to shoshonitic series.
Multiphase magmatic sulfides occur in different amounts in rocks of all
investigated areas, and, based on textural and compositional differences,
they can be classified into different types according to their
crystallisation at different stages of magma evolution (early versus late
saturation). Our results suggest that independently of the magma
composition, geodynamic setting, and association with an ore deposit, sulfide
saturation occurred in all investigated magmatic systems. Those systems
present similar initial metal contents of the magmas. However, not all
studied areas present all sulfide types, and the sulfide composition depends
on the nature of the host mineral. A decrease in the sulfide Ni∕Cu (a proxy
for the monosulfide solid solution (mss) to intermediate solid solution (iss) ratio) is
noted with magmatic evolution. At an early stage, Ni-richer, Cu-poorer
sulfides are hosted by early crystallising minerals, e.g. olivine–pyroxene,
whereas, at a later stage, Cu-rich sulfides are hosted by magnetite. The
most common sulfide type in the early saturation stage is composed of a
Cu-poor, Ni-rich (pyrrhotite mss) phase and one to two Cu-rich (cubanite,
chalcopyrite iss) phases, making up ∼84 and ∼16 area % of the sulfide, respectively. Sulfides resulting from the late
stage, consisting of Cu-rich phases (chalcopyrite, bornite, digenite iss),
are hosted exclusively by magnetite and are found only in evolved rocks
(andesites and dacites) of magmatic provinces associated with porphyry Cu
(Konya and Ecuador) and porphyry Au (Beydagi) deposits.
Magmatic sulfides in high-potassium calc-alkaline to shoshonitic and alkaline rocks
