Caracterización xeomorfolóxica e edafo sedimentaria da costa entre o Cabo Silleiro e A Guarda

The coastal stretch between Cabo Silleiro and A Guarda (Pontevedra) has a complex geomorphological organization controlled by granitic lithology, tectonic fracturing and Quaternary sedimentary evolution. Three main morphostructural units can be distinguished: the coastal corridor, dominated by rocky coasts with small beaches; the slopes connecting the mountains and the sea; and the upper level of the Serra da Groba. The interaction between tectonics and weathering processes favored the development of a dense river network embedded in the relief and the formation of Quaternary deposits of fluvial-nival origin. Among these, the Oia outcrop stands out, constituting a paleoenvironmental record of great importance, with facies of debris flows, snow flows and laminar runoff, deposited during the cold phases of the Upper Pleistocene. The associated edaphic profile shows alternating phases of sedimentation and soil formation, with intercalated paleosols dating from approximately 40,000 to 1,500 years ago, evidence of a polyphasic record associated with processes of morphogenesis and soil formation. The coídos or granite boulder beaches stand out on the coastal strip, whose genesis is related to the fragmentation of rocky platforms and the reworking of sedimentary deposits by the action of highenergy waves during the Holocene, reflecting an active and persistent coastal dynamic that continues to this day.