9402805 Becker This project is to purchase and modify a high-temperature (>350 degrees C), programmable temperature-logging tool for use in measuring subsurface temperatures in holes drilled by the Ocean Drilling Program vessel R/V JOIDES Resolution. The tool will have internal recording capability for both subsurface pressure (depth) and temperature, and may be deployed without special logging cable, allowing its use rapidly and without specialized shipboard instrumentation or deployment capabilities. The tool will be modified to allow its use from the submersible DSV Alvin, and it will be used for measuring downhole temperatures at "TAG" drill holes in the hydrothermal vent area on the Mid-Atlantic Ridge during ODP Leg 158, scheduled for September-November 1994. PI Becker will participate in Leg 158 drilling as a member of the downhole logging team. The tool will also be used during subsequent submersible diving with DSV Alvin, to reoccupy these "CORKed" holes in the seafloor at TAG to observe changes in temperature structure at these sites during 1995. Two Alvin dives are awarded to the PI for this purpose in the award. The logging tool will be available to other researchers for use on JOIDES Resolution, DSV Alvin, or other appropriate platforms in the future. ***
