The distributions suggest other venting sites north and south of the triple junction at 17 S. Fig. 15. Triangle shows location of known venting sites. Location map for the northern Mid-Atlantic Ridge and Reykjanes Ridge. Known and suspected hydrothermal sites identified in Figure 19. Thin dashed line on each plot marks the regional background value of Mn and CH 4 .
Solid circles indicate sample positions.
Only four segments or segment portions have confirmed active venting. Comparison of the global extent of plume studies and seafloor vent fluid sampling. Hydrothermal cooling is the steady state convective heat flux from a neovolcanic zone 2 km wide centered on the spreading axis.