  We propose a mechanical model for the behaviour of rocks based on progressive
damage at the elementary scale and elastic interaction. It allows us to
simulate several experimental observations: mechanical behaviour ranging from
brittle to ductile, fractal structure of the damage, powerlaw distribution of
the damage avalanches. These macroscopic properties are not incorporated at the
elementary scale, but are the results of the interaction between elements. This
emerging complexity permits us to consider the strain rock process as a complex
system characterized by non-linear dynamics.
