Kilauea volcano on the island of Hawaii is currently in a violent eruptive phase with significant activities both at the summit caldera and at several points along the East Rift Zone. This rare event provides a unique opportunity to investigate hydrothermal processes at the lava-seawater contact zone (Kapoho Bay region) and the impacts of volcanic aerosol and ash deposition on surrounding marine ecosystems. We propose to conduct an oceanographic expedition to the regions east of Kapoho and west (downwind) of the summit to collect samples and conduct experiments that will lead to a more comprehensive understanding of the marine biogeochemistry of the 2018 Kilauea eruption.