2024-03-29T12:50:33Zhttp://buleria.unileon.es/oai/requestoai:buleria.unileon.es:10612/144482022-11-23T12:24:04Zcom_10612_17col_10612_18
The origin and collapse of rock glaciers during the Bølling-Allerød interstadial: A new study case from the Cantabrian Mountains (Spain)
Santos-González, Javier
González-Gutiérrez, Rosa Blanca
Redondo-Vega, José María
Gómez-Villar, Amelia
Jomelli, Vincent
Fernández-Fernández, José M.
Andrés, Nuria
García-Ruiz, José M.
Peña-Pérez, Sergio Alberto
Melón-Nava, Adrián
Oliva, Marc
Álvarez-Martínez, Javier
Charton, Joanna
Palacios, David
Geografia Fisica
Geografía
Geología
[EN] During the Late Pleistocene, the main mountain ranges of the Iberian Peninsula were covered by small icefields and cirque and alpine glaciers. The deglaciation triggered paraglacial processes that generated landforms, mostly within the ice-free glacial cirques. In this research we analyse the deglaciation process in the Muxivén Cirque (42°15′N – 6°16′W), in the upper Sil River Basin, which includes some of the largest relict rock glaciers of the Cantabrian Mountains. We addressed this objective by means of accurate geomorphological reconstructions, sedimentological analysis, Schmidt-hammer surface weathering measurements and a dataset of 10 10Be Cosmic-Ray Exposure ages. Results reveal that after ~16 ka, glaciers retreated to the bottom of the cirques at the headwaters of the valley, leaving the walls free of ice and triggering rock avalanches onto the remnants of these glaciers. This paraglacial process supplied debris to a small glacier within Muxivén Cirque, which transformed in two rock glaciers. These debris isolated the ice inside the rock glaciers only for a very short period of time and ended up melting completely before the Younger Dryas. The lower sector of the largest one stabilized at 14.5 ± 1.5 ka, while the upper sector remained active until 13.5 ± 0.8 ka. Previous to the stabilization of the lower sector of the northern rock glacier, at its margin a high-energy debris avalanche occurred at ~14.0 ± 0.9 ka. These data agree with previous research, corroborating the paraglacial origin of most Iberian rock glaciers during the Bølling-Allerød interstadial.
2022-03-31
2022-03-31
info:eu-repo/semantics/article
0169-555X
https://www.sciencedirect.com/science/article/pii/S0169555X22000058
http://hdl.handle.net/10612/14448
10.1016/j.geomorph.2022.108112
Junta de Castilla y León LE080G19
Fundação para a Ciência e Tecnologia of Portugal PTDC/CTA-GFI/32002/2017
http://creativecommons.org/licenses/by-nc-nd/4.0/
info:eu-repo/semantics/openAccess
Attribution-NonCommercial-NoDerivatives 4.0 Internacional
Elsevier