1. Applied Geophysics Center and Dept. of Civil and Environmental Engineering and Construction, Univ. of Nevada Las Vegas, 4505 S. Maryland Parkway, Las Vegas, NV 89154-4015, US, e-mail: tamrakar@unlv.nevada.edu
2. Applied Geophysics Center and Dept. of Civil and Environmental Engineering and Construction, Univ. of Nevada Las Vegas, 4505 S. Maryland Parkway, Las Vegas, NV 89154-4015, US, e-mail: barbara.luke@unlv.edu