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This chapter provides an overview of the procedures and methods employed for coring operations and in the shipboard laboratories of the research vessel (R/V) JOIDES Resolution during International Ocean Discovery Program (IODP) Expeditions 384, 395C, and 395. Hereafter, the expeditions will be known jointly as Expedition 395 unless otherwise specified. The laboratory information applies only to shipboard work described in the Expedition Report section of the Expedition 395 Proceedings of the International Ocean Discovery Program volume that used the shipboard sample registry, imaging and analytical instruments, core description tools, and the Laboratory Information Management System (LIMS) database. Methods used by investigators for postcruise shore-based analyses of Expedition 395 project data will be documented in separate publications. 

Site U1602 is located east of the Greenland continental margin in the North Atlantic Ocean, coinciding with the northern portion of Eirik drift (Figure F1). Site U1602 is also located on a tentatively identified crustal V-shaped ridge (VSR) marked by a northeast-southwest trending linear high in the free-air gravity anomaly map and the reflection seismic profile (Figures F1, F2). This is one of the V-shaped structures that straddle the Reykjanes ridge flanks and whose origin in relation to the Iceland hotspot is debated. The site sits on oceanic crust with an age of 49.8 Ma, estimated from magnetic anomalies and plate reconstruction models. 

The intersection between the Mid-Atlantic Ridge and Iceland hotspot provides a natural laboratory where the composition and dynamics of Earth's upper mantle can be observed. Plume-ridge interaction drives variations in the melting regime, which result in a range of crustal types, including a series of V-shaped ridges (VSRs) and V-shaped troughs (VSTs) located south of Iceland. Mantle upwelling beneath Iceland dynamically supports regional bathymetry, and its variations may lead to changes in the height of oceanic gateways, which in turn control the flow of deep water on geologic timescales. Expeditions 384, 395C, and 395 recovered extensive successions of basaltic crust and thick (up to 1.3 km) overlying sediment cover, including successions through a number of contourite drifts of regional significance. Major, trace, and isotope geochemistry of basalts recovered during these expeditions will provide insight into spatial and temporal variations in mantle melting processes. Such analyses will provide data for testing the hypothesis that the Iceland plume thermally pulses on two timescales (5–10 and ~30 Ma), leading to fundamental changes in crustal architecture. This idea will be tested against alternative hypotheses involving propagating rifts and buoyant mantle upwelling. The rapidly accumulated sediments of contourite drifts have the potential to yield exceptional millennial-scale paleoceanographic records, including proxies for current strength, which is thought to be modulated by the dynamic support of the Greenland-Scotland Ridge, an oceanic gateway of global import. The recovered sediments also provide a record of subarctic climate change stretching back to the latest Eocene, including the long-term evolution of the Greenland ice sheet, critical intervals of Miocene and Pliocene warmth, the intensification of Northern Hemisphere glaciation, and Pleistocene millennial-scale variability. The objectives of Expeditions 395, 395C, and 384 are to explore the relationships between deep Earth processes, ocean circulation, and climate. These objectives were addressed by recovering sediment and basement cores from six sites, completed across three expeditions. Sites U1555 and U1563 are located at a VST/VSR pair nearest to the Reykjanes Ridge, on ~2.8 and 5.2 My old crust, respectively. Sites U1554 and U1562 are located in Björn drift above a VST/VSR pair, on ~12.4 and 14.2 My old crust, respectively. Site U1564 is located in Gardar drift above 32.4 My old oceanic crust that is devoid of V-shaped features. Finally, Site U1602 is located on the eastern Greenland margin above crust that is estimated to be Eocene in age and thus formed during the initial separation of Greenland from Scandinavia. Considered together, the sediments, basalts, and vast array of measurements collected during Expeditions 395, 395C, and 384 will provide a major advance in our understanding of mantle dynamics and the linked nature of Earth's interior, oceans, and climate. 

The Reykjanes Ridge flanks host a series of crustal V-shaped ridges (VSRs) and V-shaped troughs (VSTs) (Figure F1) whose origins are debated. Expedition 384, 395C, and 395 sites comprise a crustal flow line transect across the eastern flank of Reykjanes Ridge and one site on its western flank on the conjugate flow line. The sites sample two pairs of VSR/VST structures and provide constraints on the formation of these features. Crustal ages at site locations on the eastern flank of the slow-spreading Reykjanes Ridge are estimated to range 2.8–32 Ma; the site located to the west, near the Greenland margin, has an estimated basement age of 49 Ma. This range of ages provides a unique opportunity to quantify the timing and extent of hydrothermal fluid–rock exchange on a slow-spreading ridge that experienced rapid sedimentation and variations in tectonic architecture. 

Site U1562 is located on Björn drift, on the eastern flank of the Reykjanes Ridge in the North Atlantic Ocean. It is located ~12 km east of Site U1554 (Figures F1, F2) on a basement high at the eastern edge of the main drift deposit. Site U1562 is located on crustal V-shaped ridge (VSR) 3, which is associated with a high in the free-air gravity anomaly, whereas Site U1554 is located on V-shaped trough (VST) 2b. Site U1562 sits on ocean crust with an age of 13.86 Ma estimated from magnetic anomalies. 

Site U1554 is located on Björn drift, on the eastern flank of the Reykjanes Ridge in the North Atlantic Ocean. The Reykjanes Ridge flanks host a series of crustal V-shaped ridges (VSRs) and V-shaped troughs (VSTs) (Figure F1), whose origins and relation with Iceland mantle plume temperature variations are debated. Site U1554 is located on VST 2b, identifiable in the free-air gravity anomaly map and the reflection seismic profile (Figure F2). It sits on ocean crust with an age of 12.7 Ma estimated from magnetic anomalies and plate reconstruction models. The Reykjanes Ridge flanks are also the site of major drift deposits: Björn and Gardar drifts on the eastern flank of the ridge and Eirik drift on the eastern flank of the Greenland margin. These rapidly accumulated contourite drift sediments have the potential to record variations in past climate and ocean circulation on millennial timescales. The sedimentation rate of the drifts can serve as a proxy for deep water current strength, providing information on oceanic gateways to the Norwegian Sea and their potential ties to Iceland mantle plume behavior. 

The Reykjanes Ridge flanks host a series of crustal V-shaped ridges (VSRs) and V-shaped troughs (VSTs) (Figure F1) whose origins are debated. Expedition 384, 395C, and 395 sites comprise a crustal flow line transect across the eastern flank of Reykjanes Ridge and one site on its western flank on the conjugate flow line. The sites sample two pairs of VSR/VST structures. Crustal ages at site locations on the eastern flank of the slow-spreading Reykjanes Ridge are estimated to range 2.8–32 Ma; the site located to the west, near the Greenland margin, has an estimated basement age of 49 Ma. This range of ages provides a unique opportunity to quantify the timing and extent of hydrothermal fluid–rock exchange on a slow-spreading ridge flank that experienced rapid sedimentation and variations in tectonic architecture. Finally, the rapidly accumulated contourite drift sediments at these sites have the potential to record variations in past climate and ocean circulation on millennial timescales. 

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 southern, central, and northern 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 submarine 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 non-steady 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.