Contribution of heat outputs from high- and low-temperature hydrothermal sources to the neutrally buoyant plume at the TAG hydrothermal mound, Mid-Atlantic Ridge

We provide an estimation of the heat output necessary to generate the neutrally buoyant plume above the TAG hydrothermal mound, Mid-Atlantic Ridge, located at 26°N, using a model of plume rise in a density-stratified environment with crossflow. The estimated heat output is 460 ± 40 MW. Previous studies have estimated that the heat outputs from high-temperature hydrothermal discharge and low-temperature diffuse flow at the TAG hydrothermal mound are 90 ± 20 MW and at least 780 MW, respectively. Consequently, the contribution of diffuse flow to make the neutrally buoyant plume is 370 ± 60 MW, which accounts for approximately 80% of the heat output to the neutrally buoyant plume. As this contribution is less than 50% of the total heat output from the diffuse flow, it is likely that more than 50% of the heat output from the diffuse flow dissipates in the ambient current.