Temporal Variations in Hydrothermal Fluid Chemistry at 9-10N East Pacific Rise: Elucidating Ties to Crustal and Biological Processes

University Of New Hampshire, Durham NH

Investigators

Abstract

This is a study of the hydrothermal systems at the Ridge 2000 East Pacific Rise Integrated Studies site at 9 degrees north. During the past decade pronounced temporal variability in the hydrothermal fluids have been observed, and the chemical data have been interpreted to suggest that the changes in fluid composition reflect changes in the depth of hydrothermal circulation. Three hypotheses will be addressed in the current project. Changes in the depth of phase separation reflect changes in depth to the heat source. Magma has migrated upward and will soon erupt and/or result in another diking event. Changes in fluid compositions, reflecting changes in the pressure-temperature conditions of reaction and phase separation, are the causes of changes in the biological communities.