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Hosting both tsunami earthquakes and slow slip events at shallow depth, the northern Hikurangi margin has motivated strong research efforts over the last two decades to better understand the relation between fluid pressure and fault mechanical behavior. Recently, IODP Expeditions 372 and 375 drilled, cored, and logged the basin entering this subduction zone providing a unique opportunity to characterize initial hydrogeological and petrophysical properties that drive seismic hazards along the margin. We inventory bound and interstitial fluid contents and assess the compaction state of the heterogeneous incoming sequence by correcting shipboard total connected porosity from the bound water content that typically characterizes clay‐rich sediments. By combining mercury injection capillary pressure, nuclear magnetic resonance, and nitrogen gas adsorption, we further document the evolution of pore structure with increasing depth. We also compare porosity data at the logging and sample scales. Both logging and laboratory data evidence contrasted porosity, pore structure, and fluid distribution across the entering section. Shallow macroporous siliciclastic units show very low bound water content and undergo compaction‐induced dewatering as they are normally consolidated during burial. In contrast, mesoporous volcaniclastic Hikurangi Plateau facies are characterized by high potential for bound water release from smectite, zeolite, and opal dehydration at greater depths. They mostly exhibit very low permeability except potentially in uncemented highly porous intervals where the décollement may initiate. Macroporous to mesoporous pelagic carbonates sandwiched in between exhibit mixed behavior and may also host the future décollement, similarly to the southern part of the margin. Key Points: The Northern Hikurangi margin input section is characterized by contrasted fluid distribution, pore structure, and potential for excess pore pressure buildupIt is essential to use corrected porosity instead of apparent porosity in clay‐rich sediments and altered oceanic crustThe future décollement may develop in the lower part of pelagic carbonates or at the top of volcaniclastic facies of the Hikurangi Plateau [ABSTRACT FROM AUTHOR]

The Corinth rift (Greece) is one of the world's most active rifts. The early Plio-Pleistocene rift is preserved in the northern Peloponnese peninsula, south of the active Corinth rift. Although chronostratigraphic resolution is limited, new structural, stratigraphic and sedimentological data for an area >400 km2 record early rift evolution in three phases separated by distinct episodes of extension rate acceleration and northward fault migration associated with major erosion. Minimum total N-S extension is estimated at 6.4-7.7 km. The earliest asymmetrical, broad rift accommodated slow extension (0.6-1 mm a−1) over >3 Myrs and closed to the west. North-dipping faults with throws of 1000-2200 m defined narrow blocks (4-7 km) with little footwall relief. A N- NE flowing antecedent river system infilled significant inherited relief (Lower group). In the earliest Pleistocene, significant fluvial incision coincided with a 15 km northward rift margin migration. Extension rates increased to 2-2.5 mm a−1. The antecedent rivers then built giant Gilbert-type fan deltas (Middle group) north into a deepening lacustrine/marine basin. N-dipping, basin margin faults accommodated throws <1500 m. Delta architecture records initiation, growth and death of this fault system over ca. 800 ka. In the Middle Pleistocene, the rift margin again migrated 5 km north. Extension rate increased to 3.4-4.8 mm a−1. This transition may correspond to an unconformity in offshore lithostratigraphy. Middle group deltas were uplifted and incised as new hangingwall deltas built into the Gulf (Upper group). A final increase to present-day extension rates (11-16 mm a−1) probably occurred in the Holocene. Fault and fault block dimensions did not change significantly with time suggesting control by crustal rheological layering. Extension rate acceleration may be due to strain softening or to regional tectonic factors. [ABSTRACT FROM AUTHOR]