1. Department of Geology and Geophysics, King Saud University, Riyadh, Saudi Arabia
2. Geology Department, Assiut University, Assiut, Egypt
3. Geology Department, Faculty of Science, Fayoum University, Fayoum, Egypt
4. Geological Sciences Department, National Research Centre, Cairo, Egypt
5. Division of Geological & Planetary Sciences, California Institute of Technology, Pasadena, CA, USA