The analysis of geomorphic indicators for the definition of the extension of Pleistocenic glaciers within alpine valleys: method and applications

The paper explains the use of geomorphic indicators (such as erratic blocks and tors) as indicators of presence/absence of glacier passage during the Pleistocene. Thanks to a census of over 600 erratic blocks, and their distinction from the tors, the reconstruction of glacier extension is possible also inside the alpine valleys. As example, the paper shows the reconstruction of Pleistocene glacier extension within the Lanzo Valleys (Western Alps, Italy). The reconstruction of the Pleistocene glaciers is enough accurate for applications to geology or biology. As example, we show the application of method to the problem of origin of endemic species living in caves: thanks to the definition of the relationships between caves and glaciers during the Pleistocene, it is possible subdivide the caves in five groups with different history of habitat and of climatic changes.