PHYSICAL AND MECHANICAL VARIABILITY OF NATURAL ROCK SALT.

Petrology and micromechanics are studied for four experimentally deformed rock salts from the United States. Results show that the influence of impurity content on creep deformation decreases as temperature increases. However, the rate-controlling deformation mechanisms show similar stress and temperature dependence for each salt, independent of purity. At low temperature (25 degree C), dislocation glide dominates the deformation; whereas, at high temperature (200 degree C), dislocation climb is the predominant mechanism.