Abstract
Previous studies have used multibeam sonar data to map diffuse hydrothermal flows by exploiting the decorrelation of successive seafloor echoes caused by temperature fluctuations. The present work extends this approach to quantify temperature fluctuations integrated along the sonar line of sight. The method is illustrated using data from the Cabled Observatory Vent Imaging Sonar deployed at the Grotto Vent complex on the Endeavour Segment of the Juan de Fuca Ridge. Inversion results are presented in the form of the structure function for integrated temperature fluctuations. A three‐parameter fit to the structure function provides time series encapsulating statistics of these fluctuations.
Plain Language Summary
Measuring the heat output of diffuse low‐temperature hydrothermal flows is difficult because they typically occur over large areas and vary significantly in space and time. This paper is a first step in the direction of using sonar for such measurements. While the method cannot yet measure heat output, it can monitor the level of activity of diffuse hydrothermal discharges.
Key Points
Multibeam sonar is used to observe diffuse hydrothermal flows
The inversion method estimates spatially integrated temperature fluctuation
This is a first step in using multibeam sonar data to quantify activity level of diffuse flow discharges