Lilley 9307295 This project involves a time-series study of the hydrothermal and magmatic activities on EPR. The 1989 ARG0 survey (Haymon/Fornari) revealed an active hydrothermal field on EPR axis between 9016' and 9054' N "Tube Worm BBQ area" . AdVenture I "Alvin diving on the Venture Hydrothermal Fields" in April 1991 and AdVenture II in Feb/Mar'92 noted that eruptions are rapid one eruption took place within two weeks (dated in by 210Po/210Pb diseq.-Rubin) prior to AdVenture II and hydrothermal vents are irregularly distributed. The P.I.s surmised that this system has not yet reached steady-state. They propose to go back to this area with Alvin in an effort to monitor the evolution of the volcanic-hydrothermal system. The work will include CCD imaging, CTD measurements of water column and plume, biological activity monitoring, volcanic rock sampling,on EPR axis between 9016' and 9054' N. Scientific Justification---The P.I.s feel that by documenting the changes in volcanic and hydrothermal activities they will be able to obtain broad constraints over the period during which the system goes steady-state, and mesurement of fluxes during-steady state would give a better handle on the hydrothermal input into the chemical composition of sea-water. They will also know more about how these systems evolve through time.
