The Late Pleistocene deglaciation on Mt Sirino and Mt Pollino (Basilicata, Calabria - Southern Italy)

Abstract

The study undertaken indicated that the sediments present in some depressions on the moraines of Mt. Sirino and Mt. Pollino have analogous composition: they are formed in the lower part by deposit rich in aeolian quarz, while in the upper part they are rich in volcanic material. Only on the last moraine of Mt Sirino are there exclusively sediments formed mainly of volcanic material. Similar stratigraphy has been discovered also in some depressions on Mt. Matese and Mt. Greco moraines: on these massifs the presence of tephra and datable sediments allowed to ascertain that the transition from sediments rich in aeolian quarz and those rich in volcanic material took place around 13-14,000 years ago. All of the phases of glacial retreat, except the last at Mt. Sirino, would be datable to a period preceding ca. 14,000 years ago. The evaluation of the rise of the equilibrium line altitude (ELA) since the last glacial maximum indicated that at Mt. Pollino (2267 m) the glaciers disappeared before those at Mt. Sirino (2005 m). The presence of a glacier on the massif of lower altitude, when on the higher massif the glaciers had already disappeared, might have been attributed not so much to the slightly northernmost position, that appears unimportant, as to the different amount of precipitation. Still today the amount of precipitation that falls on Mt. Sirino is remarkably higher than that on Mt. Pollino.