One atmosphere melting experiments on ilmenite basalt 12008An evaluation of a crystal-fractionation model for Apollo 12 ilmenite basalts with melting experiments under controlled oxygen fugacities is reported. The crystallization sequence including olivine, chromium spinel, and pigeonite phases was determined, showing that the changes in melt composition are dominated by olivine crystallization and the decrease in MgO with a corresponding increase in CaO, Al2O3, and TiO2. It is concluded that the bulk composition of the ilmenite basalts was established by crystallization of olivine and minor spinel prior to the onset of pyroxene and plagioclase.
Document ID
19800039406
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Rhodes, J. M. (Massachusetts, University Amherst, Mass., United States)
Lofgren, G. E. (NASA Johnson Space Center Houston, Tex., United States)
Smith, D. P. (Lockheed Electronics Co., Inc. Houston, Tex., United States)