Solubility of water in lunar basalt at low pH2O
["Newcombe, M. E","Brett, A","Beckett, J. R","Baker, M. B","Newman, S","Guan, Y","Eiler, J. M","Stolper, E. M"]
2017-03-01
期刊论文
We report the solubility of water in Apollo 15 basaltic Yellow Glass and an iron-free basaltic analog composition at 1 atm and 1350 degrees C. We equilibrated melts in a 1-atm furnace with flowing H-2/CO2 gas mixtures that spanned similar to 8 orders of magnitude in fO(2) (from three orders of magnitude more reducing than the iron-wustite buffer, IW - 3.0, to IW 14.8) and similar to 4 orders of magnitude in pH(2)/pH(2)O (from 0.003 to 24). Based on Fourier transform infrared spectroscopy (FTIR), our quenched experimental glasses contain 69-425 ppm total water (by weight). Our results demonstrate that under the conditions of our experiments: (1) hydroxyl is the only H-bearing species detected by FTIR; (2) the solubility of water is proportional to the square root of pH(2)O in the furnace atmosphere and is independent of fO(2) and pH(2)/pH(2)O; (3) the solubility of water is very similar in both melt compositions; (4) the concentration of H-2 in our iron-free experiments is similar to 200 ppm C would be required for the vapor composition to be dominated by CO rather than H-2 at 65-75% vesicularity. (C) 2016 Elsevier Ltd. All rights reserved.
来源平台:GEOCHIMICA ET COSMOCHIMICA ACTA