North Atlantic geoid high, volcanism and glaciations

Shallow topography, geoid high and intense volcanism in the northern Mid Atlantic Ridge are interpreted as enhanced by the loading on the adjacent continents by ice caps during upper Cenozoic glaciations. The load of ice packs on the continental lithospheres of North America and northern Europe generated radial mantle flow at depth. In our model, these currents, where flowing from west and east, faced each other below the northern Atlantic, joining together and upwelling. Numerical modeling of this process supports the development of dynamic topography leading to uplift of the sea-floor and inducing a regional geoid high. The upper mantle, being pumped from the deep mantle and rising to a few km shallower than average, may have contributed to larger asthenospheric melting, and to ridge centered excess magmatism, as observed in the Northern Atlantic. Citation: Carminati, E., and C. Doglioni (2010), North Atlantic geoid high, volcanism and glaciations, Geophys. Res. Lett., 37, L03302, doi:10.1029/2009GL041663.