Sulfide melt-silicate melt distribution coefficients for nickel and iron and implications for the distribution of other chalcophile elements

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

13

Scientific paper

Distribution coefficients for Fe and Ni between sulfide and silicate melts have been determined as functions of f;O2 and f;S2. Experiments were carried out in a piston-cylinder apparatus at 1450°C and 8 kbars. In a system at sulfide saturation the f;S2, f;O2 and aFeO are interdependent; therefore, it was possible to vary f;O2/f;S2 systematically by changing the bulk Fe content of the starting materials. This was accomplished in two ways, first by varying the sulfide to silicate mass ratio and second by synthesizing silicate starting materials of differing FeO contents. The f;O2/f;S2 was further constrained by the choice of graphite capsule material combined with pre-oxidation of the starting silicate. This produced melts which were saturated or nearly saturated in C-O-S vapor. The f;O2 and f;S2 were computed from the independent relationships of f;O2/f;S2, with vapor and silicate melt compositions. The molar distribution coefficients of Ni and Fe, D(Nimol) (=XsulfNiSXsilNio) and D(Femol), exhibit strong dependencies on the molar S concentration of the sulfide melt and FeO content of the silicate melt. D(Nimol) ranges from 1458 to 8857 for sulfide melt S concentrations of 45.8 to 51.1 mol%, respectively. Negative correlations of log D(Nimol) and log D(Femol) with log (f;O2/f;S2) are consistent with reactions between sulfide and oxide components of these elements in both melts and indicate that the controlling equilibrium is MOsil + 1/2 S2 = MSsulf + 1/2 O2, (M = metal). The different values of D(Niwt) reported in the literature can be rationalized in terms of differences in f;O2/f;S2 of the experiments. It is suggested that all chalcophile elements, including PGEs, behave similarly. In particular, it is demonstrated that D(Irwt) and D(Pdwt) vary directly with the S content of the sulfide melt and indirectly with f;O2 in published experiments. For the possible range in f;O2/f;S2 of sulfide-saturated magmas in nature, variations in Ds for Ni and the other chalcophile elements of more than one order of magnitude may exist.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Sulfide melt-silicate melt distribution coefficients for nickel and iron and implications for the distribution of other chalcophile elements does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Sulfide melt-silicate melt distribution coefficients for nickel and iron and implications for the distribution of other chalcophile elements, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sulfide melt-silicate melt distribution coefficients for nickel and iron and implications for the distribution of other chalcophile elements will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1070674

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.