Shock - Induced Transition of Quartz to Stishovite
نویسندگان
چکیده
The transformation of quartz to stishovite has been studied by X-ray and optical examination of a series of experimentally shock-loaded specimens of a quartz-copper mixture. Shock pressures of 68 to 260 kb and peak temperatures of 320 ø to 870øK wer e achieved. Stishovite was identified from quartz shock-loaded above 90 kb; the quantity increases with increasing pressure, but is not dependent on temperature. The formation of stishovite under shock conditions appears to be intimately related to a short-range order phase.
منابع مشابه
Polymorphism, superheating, and amorphization of silica upon shock wave loading and release
We present a detailed and quantitative examination of the thermodynamics and phase change mechanisms (including amorphization) that occur upon shock wave loading and unloading of silica. We apply DebyeGrüneisen theory to calculate both the Hugoniot of quartz and isentropic release paths. Quartz converts to stishovite between 15 and 46 GPa without undergoing pressure-induced amorphization and pe...
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