  A simple magma accretion model of the oceanic lithosphere is proposed and its
implications for understanding the thermal field of oceanic lithosphere
examined. The new model (designated VBA) assumes existence of lateral
variations in magma accretion rates and temperatures at the boundary zone
between the lithosphere and the asthenosphere. Heat flow and bathymetry
variations calculated on the basis of the VBA model provide vastly improved
fits to respective observational datasets. The improved fits have been achieved
for the entire age range and without the need to invoke the ad-hoc hypothesis
of large-scale hydrothermal circulation in stable ocean crust. The results
suggest that estimates of global heat loss need to be downsized by at least
25%.
