TY - JOUR

T1 - Solubility of cassiterite in evolved granitic melts

T2 - Effect of T, fO2, and additional volatiles

AU - Bhalla, P.

AU - Holtz, Francois

AU - Linnen, R. L.

AU - Behrens, Harald

N1 - Funding Information: The authors appreciate the help of J. Koepke while conducting the electron microprobe analyses at the Institut für Mineralogie, Universität Hannover, Germany. Technical assistance was provided by Otto Dietrich. Helpful comments to the manuscript made by N. Chaudhri, A. Wittenberg, J. Webster, F. Farges, and O.T. Rämö are greatly appreciated. We are also greatly thankful for the Georg-Christoph-Lichtenberg fellowship from the Ministry of Science and Culture, Lower Saxony, Germany. Copyright: Copyright 2011 Elsevier B.V., All rights reserved.

PY - 2005/3

Y1 - 2005/3

N2 - The aim of this experimental study was to determine the solubility of cassiterite in natural topaz- and cassiterite-bearing granite melts at temperatures close to the solidus. Profiles of Sn concentrations at glass-crystal (SnO2) interface were determined following the method of (Harrison, T.M., Watson, E.B., 1983. Kinetics of zircon dissolution and zirconium diffusion in granitic melts of variable water content. Contributions to Mineralogy and Petrology 84, 66-72). The cassiterite concentration calculated at the SnO2-glass interface is the SnO2 solubility. Experiments were performed at 700-850 °C and 2 kbar using a natural F-bearing peraluminous granitic melt with 2.8 wt.% normative corundum. Slightly H2 O-undersaturated to H2O-saturated melt compositions were chosen in order to minimize the loss of Sn to the noble element capsule walls. At the nickel-nickel oxide assemblage (Ni-NiO) oxygen fugacity buffer, the solubility of cassiterite in melts containing 1.12 wt.% F increases from 0.32 to 1.20 wt.% SnO2 with an increasing temperature from 700 to 850 °C. At the Ni-NiO buffer and a given corundum content, SnO2 solubility increases by 10% to 20% relative to an increase of F from 0 to 1.12 wt.%. SnO2 solubility increases by ∼20% relative to increasing Cl content from 0 to 0.37 wt.% in synthetic granitic melts at 850 °C. We show that Cl is at least as important as F in controlling SnO2 solubility in evolved peraluminous melts at oxygen fugacities close to the Ni-NiO buffer. In addition to the strong effects of temperature and fO2 on SnO2 solubility, an additional controlling parameter is the amount of excess Al (corundum content). At Ni-NiO and 850 °C, SnO2 solubility increases from 0.47 to 1.10 wt.% SnO2 as the normative corundum content increases from 0.1 to 2.8 wt.%. At oxidizing conditions (Ni-NiO +2 to +3), Sn is mainly incorporated as Sn4+ and the effect of excess Al seems to be significantly weaker than at reducing conditions.

AB - The aim of this experimental study was to determine the solubility of cassiterite in natural topaz- and cassiterite-bearing granite melts at temperatures close to the solidus. Profiles of Sn concentrations at glass-crystal (SnO2) interface were determined following the method of (Harrison, T.M., Watson, E.B., 1983. Kinetics of zircon dissolution and zirconium diffusion in granitic melts of variable water content. Contributions to Mineralogy and Petrology 84, 66-72). The cassiterite concentration calculated at the SnO2-glass interface is the SnO2 solubility. Experiments were performed at 700-850 °C and 2 kbar using a natural F-bearing peraluminous granitic melt with 2.8 wt.% normative corundum. Slightly H2 O-undersaturated to H2O-saturated melt compositions were chosen in order to minimize the loss of Sn to the noble element capsule walls. At the nickel-nickel oxide assemblage (Ni-NiO) oxygen fugacity buffer, the solubility of cassiterite in melts containing 1.12 wt.% F increases from 0.32 to 1.20 wt.% SnO2 with an increasing temperature from 700 to 850 °C. At the Ni-NiO buffer and a given corundum content, SnO2 solubility increases by 10% to 20% relative to an increase of F from 0 to 1.12 wt.%. SnO2 solubility increases by ∼20% relative to increasing Cl content from 0 to 0.37 wt.% in synthetic granitic melts at 850 °C. We show that Cl is at least as important as F in controlling SnO2 solubility in evolved peraluminous melts at oxygen fugacities close to the Ni-NiO buffer. In addition to the strong effects of temperature and fO2 on SnO2 solubility, an additional controlling parameter is the amount of excess Al (corundum content). At Ni-NiO and 850 °C, SnO2 solubility increases from 0.47 to 1.10 wt.% SnO2 as the normative corundum content increases from 0.1 to 2.8 wt.%. At oxidizing conditions (Ni-NiO +2 to +3), Sn is mainly incorporated as Sn4+ and the effect of excess Al seems to be significantly weaker than at reducing conditions.

KW - Cassiterite

KW - Cl

KW - Concentration

KW - F

KW - Granite

KW - SnO solubility

UR - http://www.scopus.com/inward/record.url?scp=13244249613&partnerID=8YFLogxK

U2 - 10.1016/j.lithos.2004.06.014

DO - 10.1016/j.lithos.2004.06.014

M3 - Article

AN - SCOPUS:13244249613

VL - 80

SP - 387

EP - 400

JO - Lithos

JF - Lithos

SN - 0024-4937

IS - 1-4 SPEC. ISS.

ER -