Site U1397

Integrated Ocean Drilling Program (IODP) Site U1397 (proposed Site CARI-10B; 14°54.41′N, 61°25.35′W; 2482 meters below sea level [mbsl]) is located west of Martinique (Fig. F1). The bathymetric survey for Site U1397 revealed a region with a topographic high bound by large canyons. Site survey seismic data indicated that this site could, in the upper part, penetrate regular (unperturbed) sedimentary reflectors, whereas in the lower part some chaotic reflectors are visible. The drill site is located on the topographic high to try to avoid perturbations. Site U1397 is located very close to Core CAR-MAR 4 (7 m long) taken during the Caraval cruise in 2002. The CAR-MAR 4 core provides a sedimentary record that extends to ~32 ka, as determined by δ18O chronostratigraphy. The sedimentation rate (including tephra) is ~20 cm/k.y. (Boudon et al., submitted). Correlating the tephra sampled in the core to onshore deposits of the Montagne Pelée Volcano shows that a significantly greater number of tephra layers are deposited in the marine environment than have been identified during onshore studies (e.g., 25 tephra layers were identified in the core between 5 and 15 ka, whereas only 10 magmatic events were previously recognized in onshore studies).