Sulfur-bearing Magmatic Accessory Minerals

Temperature dependence of sulfide and sulfate solubility in olivine-saturated basaltic magmas

“…Our data confirm the higher solubility of S in anhydritesaturated magmas in comparison with that in FeS-saturated magmas (e.g., Rutherford, 1987, 1988;Luhr, 1990;Jugo et al, 2005a,b;Jugo et al, 2010;Botcharnikov et al, 2011;Parat et al, 2011) except for some peralkaline silica-rich compositions as reported by Scaillet and Macdonald (2006). Several recent spectroscopic studies have proven that S is mainly present in silicate melts as two species S 2-and S 6+ (e.g., Wilke et al, 2008;Evans et al, 2009;Métrich et al, 2009;Jugo et al, 2010).…”

Amphibole and apatite insights into the evolution and mass balance of Cl and S in magmas associated with porphyry copper deposits

“…These values are consistent with the higher oxidation state of the associated magma (NNO + 1 to NNO + 2; Chelle-Michou et al 2014, 2015a. Using a set of natural and experimental apatite/melt partitioning data for andesitic to rhyolitic melts, Parat et al (2011b) calibrated the following empirical non-Henrian partitioning relationship for sulfur between apatite and melt:…”

“…Apatite from the gabbrodiorite complex systematically returns very low sulfur concentrations (< 0.1 wt% SO 3 ). These low values may either (1) reflect low magmatic sulfur content of the basaltic magma or (2) ƒO 2 conditions at which the dominant sulfur specie is S 2− (Jugo et al 2010;Baker and Moretti 2011) and thus cannot enter the apatite structure in high amounts (Parat et al 2011b;Konecke et al 2017). At the time of apatite saturation (> 850 °C), the interstitial melt likely was fluid saturated and a fraction of the sulfur would have partitioned into the degassing magmatic fluid.…”

“…10 Probability density of estimated S concentration of the melt based on apatite from the porphyries. a Estimate using the non-Henrian partitioning function of Parat et al (2011b). b Estimate using a fixed partition coefficient of 6, which is calculated from the temperature-dependent partition coefficient calibration of Peng et al (1997) at 900 °C.…”

Detection of copiapite in the northern Mawrth Vallis region of Mars: Evidence of acid sulfate alteration

“…A possible explanation for the origin of the sulfides would be from volcanic eruptions with high concentrations of sulfide minerals. SNC meteorites have more sulfides than comparable terrestrial igneous compositions (Lorand et al, 2005) and in many terrestrial volcanic rocks, sulfides (e.g., pyrrhotite or pyrite) can occur as accessory phases (Parat et al, 2011). Weathering of sulfide minerals would have resulted in acidic conditions that could have contributed to acid leaching of materials to produce the observed ferric and mixed ferric/ferrous sulfates.…”