This data release contains porewater oxygen microprofiling data from abyssal sediment cores collected from the Samoa Basin in the South Pacific Ocean within the American Samoa Exclusive Economic Zone. Sediment cores were collected from 35 locations using a box core that was subsampled with push cores. Push cores were immediately transferred to a cold laboratory van, and oxygen was measured using Unisense microsensors inserted through pre-drilled holes in the core liner, spaced at 1 centimeter intervals. ...

Geochemical analysis of sediment core pore fluids collected from seep fields on the FK190612 research expedition in the north Pacific Ocean along the Cascadia margin in June 2019. Samples were collected to deconvolve the different processes impacting the fluid chemistry, including hydrate dissociation and clay mineral dehydration during the smectite-illite transformation that releases inter-layer water.