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The 2011 Mw9.0 Tohoku-Oki earthquake may be representative of “maximum”earthquakes: it ruptured the entire seismogenic depth range of the Japan megathrust, including the shallowest segment that reaches the trench where the displacement grew to 60 m and spawned a catastrophic tsunami. Models and direct seafloor measurements imply a comparably large initial relative motion and sustained long-period oscillations between sediment and water at the seafloor above the shallowest megathrust segment. This motion may develop enough shear to re-suspend sediment, but exclusively for the maximum earthquakes. This new co-seismic sediment-entrainment process should leave a recognizable sedimentary fingerprint of these earthquakes. Our physical experiments are testing effects of this shear between sediment and water and its interaction with high-frequency vertical shaking. We also investigate the impact of sediment properties and slope on the entrainment. We worked on several synthetic mixtures, defined according to the grain size distribution, clay mineralogy and water content with either freshwater or sea water. The grain size distribution is simplified but matches those of sediment cores from different subduction zones. For each mixture, we built matrices of the erosion rates according to the flow velocities, which shows the role of water content and vertical shaking. We have also identifi ed different mechanism during the runs:grain-by-grain or clasts entrainment, stripping, motion of the sediment interface, and formation of a dense sediment layer above the surface. These observations maybe recorded in the associated deposit, suggesting different fingerprinting by the tsunamigenic earthquakes depending on the characteristics of each subduction zone. 

The northern E-W boundary of the Caribbean Plate is primarily left lateral and has evolved through the Cenozoic from transtensive to transpressive. The southern branch of this boundary, the Enriquillo-Plantain Garden Fault (EPGF), traverses southern Haiti through the Jamaica Passage to Jamaica. Damaging earthquakes occurred in Haiti in 1751, 1770, 2010 and 2021, and in Jamaica in 1692 and 1907, yet the Jamaica Passage segment has little known seismicity with no large historic events. The EPGF in the Passage follows a 2-3 km deep trough that is less oblique to the plate motion, and was imaged previously by the 2012 HAITI-SIS seismic cruise. We present the results of an NSF-funded RAPID cruise carried out in January 2022 to the Jamaica Passage, that investigated the EPGF with a hi-res multichannel seismic system collecting >650 km of data and 47 sediment cores. We observe prominent scarps along the EPGF consistent with large seismogenic displacements, and discovered widely distributed event deposits in the cores (McHugh et al. abstract). Imaged Neogene shortening structures verge southward, and are consistent with reactivation under compression. Shortening decreases from east to west. The Matley (eastern) and Navassa (central) sub-basins feature imbricate thrusting along their northern flanks, and the Morant (western) sub-basin features open folding flanked by unfolded sediments in its central part. At the depths imaged by our data, the strain is mostly partitioned: The EPGF is sub-vertical with no consistent vertical offsets, thus accounting for only sinistral motion sub-parallel to the fault, while shortening is directed across the basins. Structures point to two distinct stress components: a regional one that drives transpression, and a spatially variable one close to the EPGF, possibly in response to minor bends along this fault. Extensional and contractional structures are superimposed at distinct times on the north flank of the EPGF, as expected of a fault that translates relative to the causative fault bends. This is an important feature related to the major fault bend west of the Morant Basin, marking the transition between the Passage and the Jamaica segment of the EPGF. The results will help us better understand the tectonics of the region and its earthquake history, and to assess the hazard for future events. 

During Expedition 386, two Giant Piston Corer (GPC) system deployments in the northern study area (Basin S3) of the southern Japan Trench (Figure F1) resulted in the recovery of cores from four holes at Site M0091 (Figure F2). The water depth was between 7802 and 7812 meters below sea level (mbsl). A breakdown of operational time is reported weekly instead of daily (see OPS in Supplementary material) due to decisions to move between sites based on weather and current conditions. Holes at Site M0091 were cored during Week 6 of the offshore phase. In total, 51.94 m of cores (Table T1) and 53.5 km of hydroacoustic profiles (see Hydroacoustics) were recovered and acquired, respectively, in the focus area. Further operations details, including winch log and inclinometer information, are found for all sites in Coring methodology in the Expedition 386 methods chapter (Strasser et al., 2023a) and associated files (see PALEOMAG and WINCHLOGS in Supplementary material). 

During Expedition 386, one Giant Piston Corer (GPC) system deployment at Basin C/N1 in the boundary area between the central and northern Japan Trench (Figure F1) resulted in the recovery of cores from two holes at Site M0093 (Figure F2). The water depth was 7454 m below sea level (mbsl). A breakdown of operational time is reported weekly instead of daily (see OPS in Supplementary material) due to decisions to move between sites based on weather and current conditions. Holes at Site M0093 were cored during Week 7 of the offshore phase. In total, 26.91 m of cores (Table T1) and 3.89 km of hydroacoustic profiles (see Hydroacoustics) were recovered and acquired, respectively, in this focus area. Further operations details, including winch log and inclinometer information, are found for all sites in Coring methodology in the Expedition 386 methods chapter (Strasser et al., 2023a) and associated files (see PALEOMAG and WINCHLOGS in Supplementary material). 

During Expedition 386, one Giant Piston Corer (GPC) system deployment at the boundary area between the central and northern Japan Trench (Figure F1) resulted in the recovery of cores from two holes at Site M0094 (Figure F2). The water depth was 7469 meters below sea level (mbsl). A breakdown of operational time is reported weekly instead of daily (see OPS in Supplementary materials) due to decisions to move between sites based on weather and current conditions. Holes at Site M0094 were acquired during Week 7 of the offshore phase. In total, 19.065 m of cores (Table T1) and 5.8 km of hydroacoustic profiles (see Hydroacoustics) were recovered and acquired in this focus area. Further operations details, including winch log and inclinometer information, are found for all sites in Coring methodology in the Expedition 386 methods chapter (Strasser et al., 2023a) and associated files (see PALEOMAG and WINCHLOGS in Supplementary materials). 

During Expedition 386, a total of five Giant Piston Corer (GPC) system deployments in the central Japan Trench (Basin C2; Figure F1) resulted in the recovery of cores from six holes at Site M0083 and four at Site M0089 (Figure F2). The water depth ranged 7602–7626 meters below sea level (mbsl). A breakdown of operational time is reported weekly instead of daily (see OPS in Supplementary material) due to decisions to move between sites based on weather and current conditions. Sites M0083 and M0089 were cored during Weeks 2–4 of the offshore phase. In this focus area, a total of 154 m of cores (Table T1) were recovered. In addition, 121 km of hydroacoustic profiles (see Hydroacoustics) were acquired. Further operations details, including winch log and inclinometer information for all sites, are found in Coring methodology in the Expedition 386 methods chapter (Strasser, 2023a) and associated files (see PALEOMAG and WINCHLOGS in Supplementary material). 

During Expedition 386, a total of five Giant Piston Corer (GPC) system deployments in the northern Japan Trench (Basin N3; Figure F1) resulted in the recovery of cores from six holes at Site M0084 and four at Site M0085 (Figure F2). The water depth was between 7590 and 7603 meters below sea level (mbsl). A breakdown of operational time is reported weekly instead of daily (see OPS in Supplementary material) due to decisions to move between sites based on weather and current conditions. Cores from Sites M0084 and M0085 were acquired during Weeks 2, 3, and 5 of the offshore phase. In total, 149.2 m of cores (Table T1) and 133 km of hydroacoustic profiles (see Hydroacoustics) were recovered and acquired, respectively, in this focus area. Further operations details, including winch log and inclinometer information, are found for all sites in Coring methodology in the Expedition 386 methods chapter (Strasser et al., 2023a) and in the associated files (see PALEOMAG and WINCHLOGS in Supplementary material). 

During Expedition 386, two Giant Piston Corer (GPC) system deployments at this study area in the northern Japan Trench (Basin N2; Figure F1) resulted in the recovery of cores from four holes at Site M0088 (Figure F2). The water depth was between 7525 and 7550 meters below sea level (mbsl). A breakdown of operational time is reported weekly instead of daily (see OPS in Supplementary material) due to decisions to move between sites based on weather and current conditions. Holes at Site M0088 were cored during Week 4 of the offshore phase. In total, 56.205 m of cores (Table T1) and 49.7 km of hydroacoustic profiles (see Hydroacoustics) were recovered and acquired in this focus area. Further operations details, including winch log and inclinometer information, are found for all sites in Coring methodology in the Expedition 386 methods chapter (Strasser et al., 2023a) and associated files (see PALEOMAG and WINCHLOGS in Supplementary material). Note that inclinometer data were not properly recorded and are therefore not reported for Site M0088. 

During Expedition 386, two Giant Piston Corer (GPC) system deployments in central Japan Trench Basin C1 (Figure F1) resulted in the recovery of cores from four holes at Site M0090 (Figure F2). The water depth was between 7445 and 7450 meters below sea level (mbsl). A breakdown of operational time is reported weekly instead of daily (see OPS in Supplementary material) due to decisions to move between sites based on weather and current conditions. Holes at Site M0090 were cored during Weeks 6 and 7 of the offshore phase. In total, 55.764 m of cores (Table T1) and 6.8 km of hydroacoustic profiles (see Hydroacoustics) were recovered and acquired, respectively, in this focus area. Further operations details, including winch log and inclinometer information, are found for all sites in Coring methodology in the Expedition 386 methods chapter (Strasser et al., 2023a) and associated files (see PALEOMAG and WINCHLOGS in Supplementary material). 

During Expedition 386, two Giant Piston Corer (GPC) system deployments in Basin C/N3 in the boundary area between the central and northern Japan Trench (Figure F1) resulted in the recovery of cores from four holes at Site M0087 (Figure F2). The water depth was between 7518 and 7520 meters below sea level (mbsl). A breakdown of operational time is reported weekly instead of daily (see OPS in Supplementary material) due to decisions to move between sites based on weather and current conditions. Holes at Site M0087 were cored during Weeks 3 and 6 of the offshore phase. In total, 47.63 m of cores (Table T1) and 69 km of hydroacoustic profiles (see Hydroacoustics) were recovered and acquired, respectively, in this focus area. In addition, one expendable bathythermograph (XBT) probe was deployed. Further operations details, including winch log and inclinometer information, are found for all sites in Coring methodology in the Expedition 386 methods chapter (Strasser et al., 2023a) and associated files (see PALEOMAG and WINCHLOGS in Supplementary material).