In this investigation we analyze the evolution of forms that constitute the Copiapo River estuarine system during the past 30 years. Through photo interpretation and field work is possible to realize that during the period, the essential forms of the estuary haven't manifest significant changes, on the other hand, estuarine complex such as the estuarine lagoon, sandy beach and dunes have presented modifications. The most significant morphological elements in order to understand these phenomena of changes have been the dynamics of waves and their spatial correlation with the width of the surf zone and dune continuum. The basic shapes present stabilization in their dynamic, which allows us to consider the estuarine system of Copiapo, a paleoestuario.