The glaciological, stratigraphic, and isotopic contexts of the Great War site of Punta Linke (Ortles-Cevedale Group)

The recent period of retreat of alpine glaciers is characterised by a marked reduction in the thickness of the glaciers also at higher altitudes, where there are emerging not only large portions of the bedrock, but also trenches and military constructions of the "White War", as is happening in Punta Linke . After the end of the Great War, the military structures were abandoned and progressively covered by snow and ice, thus preserving climatic environmental information related to this site from the end of World War I to the present. During the archaeological excavation campaign conducted in 2010, samples of ice have been collected from different contexts, for analysis at the EuroCold Lab of the University of Milan-Bicocca. The glaciological context of Punta Linke (made by the Italian Glaciological Committee in collaboration with the Provincia di Trento - Soprintendenza per i Beni Librari, Archivistici e Archeologici - Settore Beni Archeologici) includes also the reconstruction of the areal and volumetric variations of the glacial area near the archeological site, starting from the Holocene glacial maximum (Little Ice Age, culminated around the half of the 19th Century). Four pillar were sampled in different stratigraphic context (bare glacier, eternal of structure, internal of structure, in the rock tube), and subsampled for visual stratigraphy, stable isotopes, chemistry and archive. A continuous thin sections (9x9 cm) from each pillar were done for provide visual stratigraphy by single and crossed polarised images; samples from 5 to 7 cm were done for the δD and δ18O stable isotopes measurements; samples from 5 to 10 cm were done for major ions measurements. For dating purpose an aliquot by the archive were used for 136Cs measurements. The results permit to evaluate the snow filling history of the military structures from the end of the War World I.