The question posed by the Pis is whether the seafloor heat flow in the vicinity of large seamounts chains is biased towards low values by drawdown of seawater through the archipelagic aprons. A field program will be conducted to test this area of variation of heat flow in close proximity of the Hawaiian Seamount chain. Heat flow data from the vicinity of Reunion Island will also be used, along with numerical modeling, constrained by seismic and bathymetric data.