  We analyze the effect of a rough surface on shear thinning and shear
thickening fluids, modeled by power law stress tensors. The roughness is
modeled by a small wavelength and small amplitude oscillation, parametrized by
eps. We study the boundary layer corrector near the rough surface, and provide
error estimates in terms of eps for the associated wall laws. With regards to
previous studies, Mathematical difficulties arise from the nonlinearity of the
corrector equations.
