1. Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
2. MIT-WHOI Joint Program, Marine Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
3. Dipartimento di Scienze Chimiche e Geologiche, Università di Modena e Reggio Emilia, Modena, Italy.
4. Istituto di Scienze Marine, CNR, Bologna, Italy.
5. Lamont Doherty Earth Observatory, Columbia University, New York, NY 10027, USA.
6. Géosciences Montpellier, Université Montpellier & CNRS, Montpellier, France.