New geomorphological and chronological constraints for glacial deposits in the Rivoli‐Avigliana end‐moraine system and the lower Susa Valley (Western Alps, NW Italy)

A new study reveals that the Last Glacial Maximum (LGM) in the Western Alps occurred in two distinct phases, with glacier advances significantly larger and earlier than previously mapped. Using 10Be dating on boulders from glacial deposits in the Rivoli-Avigliana end-moraine system, researchers identified a pre-LGM advance between 41.2 ± 1.9 and 26.8 ± 2.1 ka, followed by two major LGM advances at 24.0 ± 1.5 ka and 19.6 ± 0.9 ka. Morphological and pedological analysis confirmed these findings, showing that the Dora Riparia glacier oscillated at its maximum extent during the first phase before a short re-advance. The study also demonstrates that the LGM ice surface reached elevations of 1000–920 m a.s.l. in the lower Susa Valley and 620–340 m a.s.l. in the amphitheatre, challenging prior reconstructions.

Ivy‐Ochs, S., Lucchesi, S., Baggio, P., Fioraso, G., Gianotti, F., Monegato, G., Graf, A. A., Akçar, N., Christl, M., Carraro, F., Forno, M. G., & Schlüchter, C. (2018). New geomorphological and chronological constraints for glacial deposits in the Rivoli‐Avigliana end‐moraine system and the lower Susa Valley (Western Alps, NW Italy). Journal of Quaternary Science, 33(5), 550–562. Portico. https://doi.org/10.1002/jqs.3034