Morphodynamics of Spanish Cantabrian Rias

Abstract

The rias are a characteristic feature of the Spanish coasts. Despite their important differences, all of them have some common problems such as those derived from infilling processes. Their littoral dynamics have been considered, with special attention to the Cantabrian coast, and a phenomenon particularly frequent in all indentated coasts has been observed: the reversion of the general direction of processes within the indented area; this phenomenon is essential to understanding the mechanisms of formation and evolution of the inlet shoals and emerged barriers of the rias, which separate their internal (sheltered) and external (open) zones; many different morphological observations have verifyed it (DIEZ, 1996 b). Current morphodynamics has been accurately approached in the ria de Foz (DIEZ, 1980-96) to get a morphodynamic model suiting the natural as well as the anthropic evolution. The balance of sediments used to verify the model (ESCOBAR et al., 1991) is justified and summarized. Data about deposit volumes at different times had to be laboriously obtained to show total consistence with the morphodynamic model insider.