Morphogenesis of the glacial lakes of the Sierras de Guadarrama and Gredos (Iberian Central System)
Glacial and periglacial geomorphological dynamics intensely shaped the relief of the mountains of the Guadarrama and Gredos ranges during the Pleistocene, giving rise to the main high mountain lakes systems of the Iberian Central System in Spain. Although these lakes share a common glacial origin, t...
| Autores: | , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2023 |
| País: | España |
| Institución: | Universidad Autónoma de Madrid |
| Repositorio: | Biblos-e Archivo. Repositorio Institucional de la UAM |
| Idioma: | inglés |
| OAI Identifier: | oai:repositorio.uam.es:10486/715247 |
| Acceso en línea: | http://hdl.handle.net/10486/715247 https://dx.doi.org/10.3989/pirineos.2023.178002 |
| Access Level: | acceso abierto |
| Palabra clave: | Iberian Central System lake tipology glacial geomorphology Sierra de Gredos Sierra de Guadarrama glacial lakes Biología y Biomedicina / Biología |
| Sumario: | Glacial and periglacial geomorphological dynamics intensely shaped the relief of the mountains of the Guadarrama and Gredos ranges during the Pleistocene, giving rise to the main high mountain lakes systems of the Iberian Central System in Spain. Although these lakes share a common glacial origin, they have different morphogenetic characteristics depending on the action of ice and its retreat in the past. In this work, for the first time, an individualised typological classification of the glacial morphogenesis of the lake basins of the Central Iberian System is carried out. For the characterisation and definition of the types, we have used morphometric variables of the lake basins and the topography of the surrounding area, geomorphological data from previous works by other authors and typological classifications of glacial lakes established in other areas at different geographical scales. On a set of 26 lakes, most of them with surface areas > 0.5 ha and maximum depths > 0.5 m, distributed in the Sierra de Guadarrama (Peñalara massif) and in the Sierra de Gredos (Central massif of Gredos, Sierra del Barco and Sierra de Béjar), 9 morphogenetic types were defined, representing the geomorphological diversity of their glacial origin. They have been classified into two genetic groups based on their origin: « hole», generated by the direct action of glacial over-deepening, and « morainic», formed by the damming of the water produced by the materials eroded, transported and deposited by glaciers. The first one includes 7 types: hole-cirque in the strict sense (s.s.), hole-cirque with moraine, hole-valley s.s., hole-valley in rosary, hole-valley lateral, hole-niche and hole-fluvial. The second group includes 2 types: moraine s.s. and intermoraine. The location in hanging niches or cirques at the headwaters, low areas, lateral depressions or fluvial axes of the valleys, the presence of rocky thresholds and narrowing of the terrain, the slopes and relief configuration, or the existence of single or multiple moraine ridges, are some of the main variables that differentiate these types. Some lakes have lost their natural condition as they have been dammed for hydroelectric and irrigation purposes, especially those of the hole-valley genetic typology |
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