NORHA, Y.A., UMR CNRS 6118 Géosciences, Université Rennes 1, Campus de Beaulieu, 263 avenue du Général Leclerc, 35042 Rennes, France. Department of Natural Sciences, Faculty of Sciences II, Lebanese University, Fanar-Matn, P.O.Box 26110217, Lebanon. Doctoral School, PRASE Lebanese University, Campus Hadath-BP5 Beirut, Lebanon., Lebanon