The Italian Mountains: Glacial landforms during deglaciation (18.9–14.6 ka)

In the mountains of peninsular Italy, a nonlinear deglaciation followed the Last Glacial Maximum (LGM), and phases of glacial readvances/standstill occurred. The LGM valley glaciers, where ice converged from various tributary cirques, fragmented into single bodies and withdrew within the glacial cirques or just beyond their threshold during the deglaciation. Compared to the LGM, the reduction of glacial tongues was of the order of 80% with a rise of the Equlibrium Line Altitude (ELA) up to 450m. The readvance and recessional phases (in the Central Apennines dated respectively from 18–19 to 16calka BP and from 16 to 14calka BP) have resulted in the formation of numerous frontal and lateral moraines, and scattered glacial deposits. The combined use of radiocarbon datings and, above all, dated stratigraphic markers (volcanic tephra and aeolian deposits) has favoured the building of a coherent chronological palimpsest of these glacial phases, ultimately leading to the identification of a glacial stage common to at least the central and southern Apennines. This stage corresponds to the 18–14ka BP time interval.