Anne Mangeney, University of Paris, Institut de Physique du Globe de Paris, Paris, France, Francois Bouchut, LAMA, CNRS, Université Paris Est, Paris, France, Enrique D. Fernández-Nieto, University of Sevilla, Sevilla, Spain, Gladys Narbona-Reina, University of Sevilla, Applied Mathematics, Sevilla, Spain, Jose Garres, University of Cordoba, Cordoba, Spain and El Hadji Kone, Institut de Physique du Globe de Paris, Paris, France