Garnet, Crystal growth, Amphibolite, Petrology-New York (State)-Adirondack Mountains, Partial melt
This study examined the hypothesis that partial melting aided the growth of large garnets in the Barton Deposit of Gore Mountain, New York. Samples of meta-gabbro and garnet amphibolite from Gore Mountain were ground into powders. The powders were then subjected to temperatures and pressures resembling the peak conditions of the Adirondack Highlands (800°C and 8 kb) using a piston cylinder press. Water was added to half of the samples to determine if an influx of water had an influence on the melting or garnet growth. After each experiment, the nickel sample holder was mounted in epoxy and ground to expose the contents of the run products. Melt was not identified within the experimental samples. The results give no evidence that partial melting had an effect on garnet growth, as melt did not appear to form readily under the peak temperature conditions. Additionally, the results of this study show that the simple addition of water did not convert the meta-gabbro into the garnet amphibolite ore. The process must be more complex than purely hydrating the meta-gabbro to become amphibolite as garnets of the hydrated meta-gabbros differed in composition from garnets of the Gore Mountain garnet amphibolite.
Axler, Jennifer Anne, "The formation of large garnets at Gore Mountain, New York : experimental partial melting of amphibolite and meta-gabbro" (2011). Theses, Dissertations, and Projects. 301.