The Stability of Gibbsite a N D Boehmite at the Surface of the Earth
نویسنده
چکیده
-Two mutually exclusive views exist concerning the relative stabilities of gibbsite and boehmite in soils. These are examined in terms of experimental and thermodynamic evidence and it is shown that all three possible divariant assemblages of two phases that can exist between gibbsite, beohmite and H20, may do so at 25~ and 1 atmosphere total pressure depending on the status of HeO. It is further shown that the conditions of H20 chemical potential needed to stabilize boehmite + H~O relative to gibbsite + H~O or gibbsite + boehmite, are unlikely to occur in natural waters in the zone of weathering.
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