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Orientador(es)
Resumo(s)
Active periglacial processes are currently marginal in the Iberian Peninsula, spatially limited to the
highest mountain ranges. However, a wide variety of periglacial deposits and landforms are distributed
in low and mid-altitude environments, which shows evidence of past periods of enhanced periglacial
activity. The purpose of this paper is to summarize the present knowledge of past periglacial activity in
the Iberian Peninsula. The chronological framework takes four main stages into account: the last
glaciation, deglaciation, Holocene and present-day processes. This study focuses on the highest massifs
(Pyrenees, Cantabrian Range, NW ranges, Central Range, Iberian Range, Sierra Nevada) as well as other
lower elevation environments, namely the central Iberian Meseta. During the last glaciation the periglacial
belt extended to much lower altitudes than today, reaching current sea level in the NW corner of
the Iberian Peninsula. A wide range of geomorphological landforms and sedimentary records is indicative
of very active periglacial processes during that phase, in some cases related to permafrost conditions (i.e.,
block streams, rock glaciers). Most of the inactive landforms and deposits in low and mid-elevations in
Iberia are also related to this phase. The massive deglaciation of the Iberian massifs was caused by a
gradual increase in temperatures. The deglaciation phase was only interrupted by a short period with
colder conditions (the Younger Dryas) that reactivated periglacial processes in the formerly glaciated
cirques of the highest lands, specifically with the widespread development of rock glaciers. During the
Holocene, periglacial processes have been only active in the highest ranges, shifting in altitude according
to temperature regimes and moisture conditions. The Little Ice Age saw the reactivation of periglacial
activity in lower elevations than today. Currently, periglacial processes are only active in elevations
exceeding 2500 m in the southern ranges and above 2000e2200 m in the northern massifs, higher in
Sierra Nevada, in the south of Iberian Peninsula.
Descrição
Palavras-chave
Last glaciation Deglaciation Iberian Peninsula Periglacial processes Holocene Climate variability
Contexto Educativo
Citação
Oliva, Marc, Serrano, E., Gómez-Ortiz, A., González-Amuchastegui, M.J., Nieuwendam, Alexandre, Palacios, D., Pérez-Alberti, A., Pellitero-Ondicol, R., Ruiz-Fernández, J., Valcárcel, M., Vieira, Goncalo, & Antoniades, D. (2016). Spatial and temporal variability of periglaciation of the Iberian Peninsula. Quaternary Science Reviews, 137, 176-199. https://doi.org/10.1016/j.quascirev.2016.02.017
Editora
Elsevier
