An occurrence of metastable cristobalite in high-pressure garnet Granulite
January 1, 1997
High-pressure (0.8 gigapascals) granulite facies garnet from Gore Mountain, New York, hosts multiple solid inclusions containing the low- pressure silica polymorph cristobalite along with albite and minor ilmenite. Identification of cristobalite is based on Raman spectra, electron microprobe analysis, and microthermometric measurements on the ??/?? phase transformation. The cristobalite plus albite inclusions may have originated as small, trapped samples of hydrous sodium-aluminum-siliceous melt. Diffusive loss of water from these inclusions under isothermal, isochoric conditions may have resulted in a large enough internal pressure decrease to promote the metastable crystallization of cristobalite.
Citation Information
Publication Year | 1997 |
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Title | An occurrence of metastable cristobalite in high-pressure garnet Granulite |
DOI | 10.1126/science.276.5309.91 |
Authors | R.S. Darling, I.-Ming Chou, R.J. Bodnar |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Science |
Index ID | 70019895 |
Record Source | USGS Publications Warehouse |