Glacier variations in the European Alps at the end of the last glaciation

espanolEl ultimo maximo glaciar en los Alpes duro desde aproximadamente 30 a 19 ka. Los glaciares alcanzaron la parte mas externa de ambos lados de las principales cadenas alpinas, formando lobulos de piedemonte en el norte y rellenando los anfiteatros italianos en el sur. El paron de los glaciares desde su maxima extension ocurrio no mas tarde de 24 ka. Los glaciares oscilaron con pequenos reavances durante varios miles de anos, dando lugar a las morrenas estadiales del Ultimo Maximo Glaciar. Al norte y al sur de los Alpes los diferentes estadiales no presentan una exacta correspondencia. Los glaciares retrocedieron hacia el interior de la montana hacia 19-18 ka. Durante la fase mas temprana de retroceso del hielo en el Tardiglacial los lobulos de hielo que llegaban hasta el piedemonte, fundieron en los extensos lagos que se formaron en los tramos inferiores de los valles. El primer reavance glaciar alpino tuvo lugar durante el estadial Gschnitz, 17-16 ka, que fue probablemente la respuesta al enfriamiento del evento 1 de Heinrich. Durante el interstadial Bolling/Allerod la mayor parte de los Alpes estaba libre de hielo. Los glaciares avanzaron repetidamente con una extension de varios kilometros desde la cabecera de los circos durante el estadial Egesen como respuesta al periodo frio del Younger Dryas. Las morrenas Egesen, en algunos sitios varios conjuntos de morrenas, fueron construidas en muchos valles de los Alpes. Las fechas cosmogenicas (10Be) de las morrenas del estadial Egesen se han datado entre 13,5 y 12 ka. Las morrenas situadas en una posicion intermedia entre las morrenas de la Pequena Edad del Hielo y las morrenas Egesen se formaron en las margenes de glaciares que avanzaron durante la ultima etapa del estadial Egesen o a comienzos del Holoceno, hace 10,5 ka. EnglishThe Last Glacial Maximum in the Alps lasted from approximately 30 to 19 ka. Glaciers reached out onto the forelands on both sides of the main Alpine chains, forming piedmont lobes in the north and filling the Italian amphitheatres to the south. Pullback of glaciers from their maximum extent was underway by 24 ka. Glaciers oscillated at stillstand and minor re-advance positions for several thousand years forming Last Glacial Maximum (LGM) stadial moraines. North and south of the Alps, the various stadials cannot yet be unequivocally matched. Glaciers had receded back within the mountain front by 19-18 ka. During the early Lateglacial phase of ice decay remnants of the once huge valley glaciers that fed the piedmont lobes downwasted and were likely calving into the extensive lakes that formed in the lower valley reaches. The first Alpine-wide glacier re-advance took place during the Gschnitz stadial, 17-16 ka, which was likely a response to Europe-wide cooling during Heinrich event 1. By the Bolling/Allerod interstadial much of the Alps were ice-free. Glaciers advanced repeatedly to an extent several kilometers from the cirque headwalls, during the Egesen stadial in response to the Younger Dryas cold period. Egesen stadial moraines, at some sites several sets of moraines, were constructed in valleys all across the Alps. 10Be exposure dates for Egesen stadial moraines are in the range 13.5 to 12 ka. Moraines located at an intermediate position between the Little Ice Age moraines and the Egesen moraines formed at the margins of glaciers that advanced during the closing phase of the Egesen stadial or during the earliest Holocene at 10.5 ka.