Formas e depósitos glaciares e periglaciares no Xeoparque Montañas do Courel (Galicia)

galegoAs Montanas do Courel atopanse en Galicia, no Noroeste da Peninsula Iberica, entre as coordenadas 42,715o N; 42,32o N e 7,023o O; 7,42o O. O seu relevo esta caracterizado pola presenza dun conxunto de vales encaixados e interfluviais estreitos que se alonga practicamente de Norte a Sur. Litoloxicamente dominan as lousas, cuar-citas e calcarias con pequenos afloramentos de diabasas. Os materiais estan intensamente fracturados por mor da dinamica tectonica que se puxo en marcha a partires do Cenozoico. Destacan de xeito especial as fallas de desgarro (strike slip fault) que presentan unha direccion xeral NNL-SSO. Ademais, ollanse outros sistemas de fracturas que levan direccions NO-SL ou O-L, que fragmentaron o terreo e delimitaron un amplo conxunto de bloques con formas sigmoides que marcan o deseno xeral de moitos sectores do territorio. A rede fluvial esta moi condicionada por este sistema de descontinuidades que dirixen o percorrido xeral dos vales, pero tamen, e dun xeito singular, pola litoloxia.Durante o Plistoceno recente, nunha data que esta por determinar mais posiblemente vai entre mais de 40.000 anos e 11.000, o clima dominante era frio con intres de diferente temperatura e humidade. Iso provocou a remodelacion de moitos sectores por mor de procesos glaciares e periglaciares. As pegadas dos primeiros que-daron marcadas en formas erosivas, caso de circos e umbrais rochosos, ou acumulativas, caso de cristas more-nicas. Os segundos en depositos estratificados de aba ou en espectaculares abas de bloques. EnglishThe Courel Mountains are located in Galicia, Northwest Iberian Peninsula (between 42.715° N; 42.32° N and 7.023° W; 7.42° W). Their relief is characterized by a group of embedded valleys and cramped watersheds that expand in a North-South direction. The sector is lithologically dominated by slabs, quartzites and limestones with small outcrops of diabase. The materials are intensively fractured by tectonic dynamics set up after the Cenozoic, with strike slip faults showing a prevailing NNE-SSW direction. Also, other fracture systems appear in this sector with directions NW-SE and W-E that fragmented the terrain and delimited a great cluster of blocks with sigmoidal shapes defining large sectors. The fluvial network is very much conditioned by this system of discontinuities that direct the general course of the valleys, but also, and in a singular way, by litho-logy. During the recent Pleistocene, possibly between ca. 40.000 and 11.000 years, the dominant climate was cold with alternating phases of different temperature and moisture conditions. This caused the remodelling of large sectors by glacial and periglacial processes. Glacial activity favoured the development of erosive lan-dforms, such as glacial cirques and glacial threshold, and accumulative features such as the moraine systems. Periglacial processes favoured the deposition of thick debris mantles covering the slopes.