Chromium basalts - Experimental determination of redox states and partitioning among synthetic silicate phasesExperiments were performed on silicate compositions in the forsterite-anorthite-silica and forsterite-anorthite-diopside systems to determine the relative amounts of Cr(II), Cr(III), and Cr(VI) over a wide range of oxygen partial pressures from 10 to the -10th to 1 atm at 1500 and 1550 C. Redox states were measured by visible absorption spectroscopy and electron paramagnetic resonance spectroscopy and titration. It was found that Cr is present almost exclusively as Cr(III) in terrestrial basaltic liquids and as a mixture of Cr(III) and Cr(II) in lunar basaltic liquids.
Document ID
19770051874
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Schreiber, H. D. (NASA Johnson Space Center Houston, Tex.; Wisconsin, University, Madison, Wis., United States)
Haskin, L. A. (NASA Johnson Space Center Houston, Tex., United States)