Comment on "mantle flow drives the subsidence of oceanic plates"

Adam and Vidal (Reports, 2 April 2010, p. 83) reported sea-floor depth increasing as the square root of distance from the ridge along "mantle flow lines." However, their data actually support a depth-age relationship and "flattening" at older ages. We argue that no plausible physical mechanism supports their proposal that mantle flow drives subsidence.