Rapid deglaciation during the Bølling-Allerød Interstadial in the Central Pyrenees and associated glacial and periglacial landforms

The Central Pyrenees hosted a large ice cap during the Late Pleistocene. cirques under relatively low-altitude peaks (2200–2800 m) include greatest variety of glacial landforms (moraines, fossil debris-covered glaciers and rock glaciers), but their age formation process are poorly known. Here, we focus on headwaters Garonne River, namely Bacivèr Cirque (highest at ~2600 m), with widespread erosive depositional periglacial landforms. We reconstruct pattern deglaciation from geomorphological observations 17-sample dataset 10Be Cosmic-Ray Exposure (CRE) ages. Ice thickness in must have reached ~200 m maximum extent last cycle, when it flowed down towards paleoglacier. However, by ~15 ka, Bølling-Allerød (B-A) Interstadial, mouth cirque was deglaciated as tributary glacier shrank disconnected Glacial retreat rapid, whole likely to been only few centuries, while paraglacial processes accelerated, leading transformation debris-free into final stages. Climate conditions prevailing transition between B-A Younger Dryas (YD) favored growth development small moraines within slopes walls ~12.9 dating uncertainties make impossible state whether these formed or YD. melting dynamics, which promoted well glaciers. These remained active throughout Early Holocene until least ~7 ka. Since then, landscape has seen period relative stability. A similar chronological sequence also detected other below 3000 m. As mid-latitude mountain regions, triggered complete paleoglacier wide existing cirque.