Turbulent-like fluctuations in quasistatic flow of granular media
  We analyze particle velocity fluctuations in a simulated granular system subjected to homogeneous quasistatic shearing. We show that these fluctuations share the following scaling characteristics of fluid turbulence in spite of their different physical origins: 1) Scale-dependent probability distribution with non-Guassian broadening at small time scales; 2) Power-law spectrum, reflecting long-range correlations and the self-affine nature of the fluctuations; 3) Superdiffusion with respect to the mean background flow. 
F. Radjai, S. Roux