Affiliation: | [1]Dr. Geolittomer, UMR 6554 LETG, Universite de Nantes, BP 81227,44312, Nantes, France,E-mail: mohamed.maanan@univ-nantes, fr [2]Dr. Marine Geosciences Laboratory URAC 45, Earth Sciences department, Faculty of Sciences, 24000 E1 Jadida, Morocco. [3]Dr. Universidad Nacional Aut6noma de M6xico. Instituto de Ciencias del Mar y Limnologia. Calz. J. Montes Camarena, Mexico |