Dehydration-Melting and Fluid Recycling during Metamorphism: Rangeley Formation, New Hampshire, USA
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چکیده
reflect the dewatering of structurally lower levels after nappe emMuscovite and biotite dehydration-melting reactions near the peak placement. If so, then nappe emplacement occurred at T~475°C. of metamorphism played a significant role in the reaction and fluid history of the Rangeley Formation in southwestern New Hampshire, USA. Evidence for in situ melting includes: (1) the consistency among theoretical phase equilibria, observed reaction textures, and the inferred P–T conditions; (2) disseminated, centimeter-scale,
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