Equilibrium experiments in the system MgO-SiO2-H2O (MSH): stability fields of clinohumite-OH [Mg9Si4O16(OH)2], chondrodite-OH [Mg5Si2O8(OH)2] and phase A (Mg7Si2O8(OH)6)
Article Abstract:
The equilibrium conditions hindering the stability fields of clinohumite-OH, chondrodite-OH and phase A were investigated through reversed equilibrium experiments of up to 100 kilobar within the MgO-SiO2-H2O system. Only seven out of 12 Dense Hydrous Magnesium Silicates were known to be synthesized at pressures less than or equal to 100 kbar. The large stability fields of clinohumite-OH and chondrodite-OH went beyond pressure ranges of 80 kbar although breakdown assemblages from the humite-group phases were not distinct and breakdown of phase A was observed at higher temperatures.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1998
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Ferric iron content of mineral inclusions in diamonds from George Creek, Colorado determined using Mossbauer spectroscopy
Article Abstract:
Application of the Mossbauer milliprobe to a suite of diamonds of eclogitic paragenesis yielded Fe 3+/episilon Fe ranges of 0-7% for garnets and 8-14% for clinopyroxene. These findings are consistent with low oxygen fugacity conditions implied by the presence of the inclusions in diamond. The inclusions in diamonds are generally considered vital to the preservation of oxidation states at the time of diamond formation. These inclusions provide information on mantle source region and the genesis of diamond.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1998
User Contributions:
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