Periglacial features in Las Ubiñas Massif (Cantabrian Mountains)
Currently there are two active periglacial belts in Las Ubiñas Massif: the nivoperiglacial, located between 1750-1800 and 2100-2200 meters a.s.l.; and the cryonival, located above 2100-2200 meters a.s.l. to the top of the massif at 2417 meters a.s.l. (Fontán Sur). The nivoperiglacial belt, where the...
Main Authors: | , , |
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Format: | Article in Journal/Newspaper |
Language: | Spanish |
Published: |
Universidade da Coruña, Servizo de Publicacións
2022
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Subjects: | |
Online Access: | https://revistas.udc.es/index.php/CADLAXE/article/view/cadlaxe.2022.44.0.9425 https://doi.org/10.17979/cadlaxe.2022.44.0.9425 |
Summary: | Currently there are two active periglacial belts in Las Ubiñas Massif: the nivoperiglacial, located between 1750-1800 and 2100-2200 meters a.s.l.; and the cryonival, located above 2100-2200 meters a.s.l. to the top of the massif at 2417 meters a.s.l. (Fontán Sur). The nivoperiglacial belt, where the processes are more attenuated and the snow determines the geomorphological activity, is characterized by stable snow sheets between six and eight months per year, frequently triggering snow avalanches, as well as debris flows and landslides, Solifluction, streams and nival karst processes are also present. On the other hand, few freeze-thaw cycles have been observed in this belt. For its part, in the cryonival belt an intensification of the aforementioned processes can be seen, with the exception of snow avalanches, due to lower temperatures, around 1 ºC and 3 ºC on average per year, and a greater presence and duration of the snow and permanent snow patches. At these levels, cryoturbation generates patterned ground features such as stone stripes and stone-sorted circles. En la actualidad existen dos pisos periglaciares activos en el Macizo de las Ubiñas: el nivoperiglaciar, situado entre 1750-1800 y 2100-2200 metros s.n.m.; y el crionival, ubicado por encima de 2100-2200 metros s.n.m. hasta el techo del macizo a 2417 metros s.n.m. (Fontán Sur). El piso nivoperiglaciar, donde los procesos son más atenuados y la nieve determina la actividad geomorfológica, se caracteriza por mantos nivales estables entre seis y ocho meses al año, siendo frecuente que se desencadenen aludes de nieve, así como movimientos en masa rápidos como los flujos de derrubios, los argayos y las fanas, además de otros de movimiento más lento como la solifluxión, la arroyada y el karst nival, aunque se han observado escasos ciclos de hielo-deshielo. Por su parte, en el piso crionival se aprecia una intensificación de los procesos anteriormente mencionados, a excepción de la caída de aludes, debido a unas temperaturas inferiores, en torno a 1 ºC y ... |
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