Acoustic imaging of high-temperature hydrothermal plumes at seafloor spreading centers

Abstract

We explore the possibility of using active sonar techniques to acoustically image high-temperature ‘‘black smoker’’ hydrothermal plumes. We examine recent sonar images of a hydrothermal vent field at 11°N on the East Pacific Rise obtained from DSRV Alvin which may show the presence of plumes. For vent fields on the East Pacific Rise estimates are obtained of the minimum detectable concentration of precipitates as a function of the range between the sonar and the plume boundary. These estimates are compared with measured concentrations. Some of the anticipated advantages of acoustic imaging are discussed. We conclude that acoustic imaging techniques have the potential of providing a coherent framework for point sampling of physical and chemical properties of hydrothermal plumes and for determining the dynamics of their injection into the surrounding water mass.