Nazem M. El-Radaideh     nazem@yu.edu.jo   http://faculty.yu.edu.jo/nazem     nazemelradaideh@yahoo.com  Department of Earth and environmental sciences- Faculty of science Yarmouk University Irbid - Jordan Tel.  ( office):(962)-7211111 (ext.) 2917 or 2920   

nazem@yu.edu.jo