Glaciers fluctuations during the Lateglacial and the Holocene in Georgian Greater Caucasus from ¹⁰ Be moraine dating

Glaciers of the Greater Caucasus are sensitive archives of past climate variability, however little is known about their long-term history. In this study we reconstruct the fluctuations of the Shkhara (42°58′23″N 43°6′0″E) and Namkuami (42°57′57″N 43°7′35″E) glaciers, which were coalescent in the past to form one of the largest glaciated body in the Georgian Caucasus located in the upper Enguri River basin. We combine geomorphological mapping and cosmic-ray exposure dating methods (Beryllium-10) applied to a set of 51 samples from 12 moraines. Results show one moraine dated to the Lateglacial at ~16 ka, five Holocene glacial stages dated to ~5.6, ~2.3, ~1.5, ~1.0 ka, and at least three advances during the Little Ice Age (~0.4–0.5 ka). The absence of Early Holocene moraines suggests smaller glacier extent during this period compared to the Mid/Late-Holocene transition, when the oldest and most extensive Holocene moraines were deposited. The reduced size of the Georgian glaciers during the Early Holocene and the multiphased advances during the Late-Holocene is similar to what is observed on the northern slopes of the Russian Caucasus. The reconstructed chronology provides essential temporal constraints for exploring Holocene environmental change and human-climate interactions in the Caucasus, a key region for Neolithic human expansion and subsequent cultural development.