Influencia de la glaciación en la red de drenaje: el ejemplo de los valles de Respina y Rebueno (Alto Porma, Cordillera Cantábrica, noroeste de España)

Abstract

The study addresses two valleys in the river Porma basin, on the southern slope of the Cantabrian Mountains, Spain. In the first one, the Respina Valley, there are many glacial evidences, such as cirques, moraines, till or erratic boulders, demonstrating the importance of the glaciation in this valley. The second one, the Rebueno Valley, shows very few glacial landforms restricted to the upper section of the valley. The comparison of the longitudinal and transverse profiles of both valleys, show the great influence of glaciation in the Respina valley relief, contrasting with the fluvial landforms generated in Rebueno valley. In both, distinct geomorphological processes modulated the relief in such a manner that, despite their proximity, they show significant differences in landscape. In addition, the paper addresses the influence of glaciation on the current configuration of the drainage network, which has scarcely been discussed previously. The main changes in drainage network are the generation of a new valley as a result of a big moraine from Silván valley that deviated the Respina river to the south. This is a very significant example of the importance of the glaciation in river network configuration in the Cantabrian Mountains.