A directed avalanche model with a control parameter is introduced to describe the transition between cohesive and noncohesive granular material. The underlying dynamics of the process can be mapped to interface growth model. In that representation, a continuous phase transition separates the rough phase and the flat phase. In the avalanche formulation, this corresponds to a transition from deep to shallow avalanches. The scaling exponents of the avalanches indeed follow those of the underlying

more »

... nterface growth in both phases and at the transition point. However, the mass hyperscaling relation is broken at the transition point due to the fractal nature of the avalanche and a hierarchy of critical directed percolation processes.