1. Research Associate, Dept. of Civil and Environmental Engineering, Univ. of Alberta, 9211—116 St., NW Edmonton, AB, Canada T6G 1H9.
2. Associate Professor, State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, Hubei 430071, China.
3. Research Associate, Dept. of Civil and Environmental Engineering, Center for Experimental Study of Subsurface Environmental Processes, Colorado School of Mines, 1500 Illinois St., Golden, CO 80401.
4. Professor, Dept. of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois St., Golden, CO 80401.
5. Assistant Professor, Dept. of Civil and Environmental Engineering, Center for Experimental Study of Subsurface Environmental Processes, Colorado School of Mines, 1500 Illinois St., Golden, CO 80401.
6. Professor, Dept. of Geosciences, Univ. of Colorado Boulder, Boulder, CO 80309-0399.
7. Professor, Dept. of Energy Resources Engineering, Stanford Univ., 367 Panama St., Stanford, CA 94305.
8. Associate Professor, Dept. of Structural Engineering, Univ. of California San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0085 (corresponding author).