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We review scientific ocean drilling of the New Jersey passive continental margin and the success of Integrated Ocean Drilling Program (IODP1) Expedition 313 in addressing long-standing, fundamental issues of sequence stratigraphy, sea-level change, and resources. The New Jersey margin was targeted for study by several generations of ocean drilling because of its thick, prograding Oligocene to Quaternary sequences bounded by unconformities. Coring and logging on the onshore coastal plain (Ocean Drilling Program [ODP] Legs 150Xh ttp://www-odp.tamu.edu/publications/citations/cite150X.html and 174AX), outer continental shelf (Leg 174A), and continental slope and rise (Legs 95, 150, and 174A) provided a chronology of sea-level lowerings but did not sample facies needed to evaluate Miocene sea-level amplitudes. Expedition 313 used a Mission Specific Platform (L/B Kayd) to drill on the shallow continental shelf, recover critical Miocene facies, particularly on clinoform foresets, and capture the full amplitudes of relative sea-level changes. Expedition 313 overcame challenging borehole conditions and recovered a total of 1311 m of core at three sites (81 % recovery) that: (1) correlated difficult-to-date nearshore-shelf facies to the time scale with resolution better than ±0.5 million years (Myr); (2) tested and confirmed that sequence boundaries are a primary cause of seismic reflections on siliciclastic shelves; (3) tested sequence stratigraphic models with core-log-seismic integration; and (4) provided a record of paleodepth changes through time that constrained amplitudes of Miocene sea-level change, including the influence of mantle dynamic topography. The New Jersey relative sea-level estimates are similar to those obtained using stable isotopes and Mg/Ca paleothermometry, showing that GMGSL (“eustasy”) varied with 10–60 m scale amplitudes on the Myr scale. Drilling beneath the shallow continental shelf also identified groundwater sources, including seawater, deepsourced brines, and meteoric fresh water, that represent potential resources for future generations. Studies of this margin have implications for future subsurface storage of supercritical CO2 and geotechnical issues relating to the location of offshore wind infrastructure. Expedition 313 demonstrated the feasibility of continuously recovering and logging strata in shallow water, providing constraints on sea level, sequences, hydrogeology, and resources. 

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). 

Short historical and even shorter instrumental records limit our perspective of earthquake maximum magnitude and recurrence and thus are inadequate to fully characterize Earth’s complex and multiscale seismic behavior and its consequences. Motivated by the mission to fill the gap in long-term paleoseismic records of giant (Mw 9 class) subduction zone earthquakes, such as the Tohoku-Oki earthquake in 2011, International Ocean Discovery Program Expedition 386 successfully collected 29 giant piston cores at 15 sites (total core recovery = 831.19 m), recovering up to 37.82 m long, continuous upper Pleistocene to Holocene stratigraphic successions of 11 individual trench-fill basins that are expected to have recorded past earthquakes. Preliminary expedition results document event-stratigraphic successions comprising numerous event deposits and initially characterize their different types, facies, properties, composition, and frequency of occurrence, which show spatial variations across the entire Japan Trench. The occurrence of several tephra beds, radiolarian biostratigraphic events, and characteristic variations of paleomagnetic declination and inclination that probably represent paleomagnetic secular variation reveal high potential for establishing robust age models in all parts of the Japan Trench. The central Japan Trench models are most likely to cover the longest timescales, with expected age ranges reaching back to ~24 ka. Together, these preliminary initial results indicate that the applied concept and strategy of multisite coring will likely be successful to test and further develop sub-marine paleoseismology to extract megathrust earthquake signals from event-stratigraphic sequences preserved in the sedimentary record. Obtained data and samples will now be examined using postexpedition multimethod applications to comprehensively characterize and date event deposits. Detailed work will include detailed characterization of the sedimentologic, physical, and (bio-)geochemical features; stratigraphic expressions of relationships; and spatiotemporal distribution of event beds. These will be analyzed as foundational proxy evidence for distinguishing giant earthquakes from smaller earthquakes and aseismic processes driving mechanisms to ultimately develop a long-term record of giant earthquakes. Furthermore, Expedition 386 achievements comprise the first ever high temporal and high spatial resolution subsurface investigation and sampling in a hadal oceanic trench, which are the deepest and least explored environments on our planet. Preliminary initial results show high total organic carbon content and downcore pore water and headspace gas profiles with characteristic changes related to organic matter degradation. In combination, these are suggestive of the occurrence of intensive remineralization and reveal evidence of nonsteady-state behavior. Together with the successful offshore sampling for microbiology postexpedition analyses and research, this provides exciting new perspectives to advance our understanding of deep-sea elemental cycles and their influence on hadal environments.