9418105 Carmichael A series of experiments that will produce a compact expression relating intensive variables to the composition and stability of biotite in natural liquids are planned. The experiments will determine (1) the iron redox equilibrium of the hydrous mineral biotite as a function of liquid composition, temperature and oxygen fugacity, (2) the conditions for biotite appearing as an early crystallizing phase in natural liquids, and (3) the solubility of water in natural silicate liquids from 0.5 to 2.5 kbars.
