Geological observations of mantle flow-driven dynamic topography are
numerous, especially in the stratigraphy of sedimentary basins; on the
contrary, when it leads to subaerial exposure of rocks, dynamic
topography must be substantially eroded to leave a noticeable trace in
the geological record. Here, we demonstrate that despite its low
amplitude and long wavelength and thus very low slopes, dynamic
topography is efficiently eroded by fluvial erosion, providing that
drainage is strongly perturbed by the mantle flow driven surface uplift.
Using simple scaling arguments, as well as a very efficient surface
processes model, we show that dynamic topography erodes in direct
proportion to its wavelength. We demonstrate that the recent deep
erosion experienced in the Colorado Plateau and in central Patagonia is
likely to be related to the passage of a wave of dynamic topography
generated by mantle upwelling.