Paper No. 37-4
Presentation Time: 2:35 PM
THE INFLUENCE OF HYDROUS MELTING ON THE ELECTRICAL CONDUCTIVITY IN FELDSPAR LABRADORITE
The electrical conductivity of a single crystal of feldspar labradorite has been carried out under hydration melting conditions at 1 GPa. Hydration and melting were achieved by enclosing the sample in a talc sleeve and carrying out the conductivity measurements above the dehydration temperature of talc (800oC), which is also the melting point of most plagioclase feldspars at ambient pressure. Electrical conductivity measurements were obtained using the impedance spectroscopy method at temperatures between 300oC and 1100oC and the conductivity behavior in labradorite determined upon melting. At least 800 ppm wt. uptake of water was measured in the crystal at saturated water conditions. The electrical conductivity in single crystal labradorite has been analysed using the Hashin and Shtrikman mixing model to determine the melt fraction and hydrous melt conductivity in the mineral.