RUI: Energies of Mineral and Rock Processes

Lafayette College, Easton PA

Investigators

Abstract

Hovis EAR-0000523 The Solution Calorimetry Laboratory at Lafayette College engages in the investigation of the thermodynamic properties and behavior of geologically significant materials. During the grant period the energetics of glasses/liquids will be investigated in simple systems in order to relate established immiscibility to enthalpies of mixing and to develop configurational entropy models that will test the validity of Adams-Gibbs models developed from viscosity data. Zeolites will be the first amorphized silicates to be investigated calorimetrically, the primary objects of the study being to understand fundamental nature of these materials, their differences from thermally amorphized analogs, and the behavior of "water" in amorphous materials. An ongoing study of felsic water-bearing magmatic systems will be brought to conclusion, yielding information on the thermal budgets of hydrous magmas and quantifying the energetics of speciation in the context of spectroscopic data. Mixing energies will be measured for K-Rb and other feldspar systems in the hope of developing generalized mixing models. Measurement of enthalpies associated with alkali-water-vacancy coupled substitution will be concluded for the analcime - pollucite and analcime - Rb-leucite systems. The critical temperature of high-Si nepheline - kalsilite will be determined in an effort to connect K-Na mixing properties to phase behavior. A quantitative study of energies associated with microstructures in halide minerals will be initiated. A number of these projects will involve collaborative efforts with scientists in the United States, the United Kingdom, France, and Germany. Several projects, including one on the thermal expansion of nepheline - kalsilite minerals, have been developed specifically for undergraduate participation. These projects will teach students about the methods, philosophy, and importance of scientific research.