Abstract

An activation energy of 19.6 ± 3.5 kcal/mole was found for conversion of synthetic beidellite with the composition Al2Si3.66Al0.34O10(OH)2K0.34 to mixed-layer illite/smectite. The size of this activation energy and the rate constants suggest that (1) the alteration of smectite to illite during diagenesis involves the breaking of chemical bonds in the 2:1 layers; (2) either an equilibrium or a kinetic interpretation for the range of mixed layering found in burial diagenetic sequences is compatible with the kinetic data; and (3) the formation of illite from smectite on the ocean floor will not be seen, even if the reaction is favored thermodynamically, because the reaction rate is too slow.

You do not currently have access to this article.