The objective of this project is to directly chemically analyze fluid inclusions from quartz veins from oceanic rocks. Well-characterized, homogeneous fluid inclusion populations on rocks already in hand will be analyzed by conventional crush/ leach analysis using atomic absorption spectrophotometry. This data can then be compared to hydrothermal end members sampled from active hot springs. %%% Fluid inclusion studies provide important information about the temperature of hydrothermal systems and about the salinity of the fluid. There has been no previous attempt to determine directly the chemical composition of the fluid trapped in the inclusion and such information is important to a complete characterization of the hydrothermal system. It would be extremely useful to be able to compare fluid compositions in inclusions in fossil systems with compositions of presently active seafloor systems. The data to be obtained in this project could break new ground.