Glaciers and mass movements in the Hüttwinkl Valley (Hohe Tauern range): from the Last Glacial Maximum (LGM) until now

Abstract

Abstract. The Hüttwinkl Valley, the uppermost section of the Rauris Valley, offers a unique sedimentary and morphological archive to study the development of the landscape in a high-Alpine valley since the Last Glacial Maximum (LGM). Glacial extents of the past, especially during the Younger Dryas (12.8–11.7 ka) and the Little Ice Age, as well as the present-day massive glacier retreat, are clearly recorded. On the other hand, the effects of different mass movements on valley development are evident. The field trip begins in Kolm-Saigurn, where the Durchgangwald landslide occurred in the Bølling–Allerød interstadial (14.7–12.9 ka). In the Younger Dryas (12.9–11.7 ka) glaciers overflowed parts of the Durchgangwald landslide deposit followed by the Lenzanger landslide (Preboreal, Early Holocene). North of Kolm-Saigurn, the Bucheben landslide (Early Holocene) and the Lechnerhäusel landslide (Middle Holocene) showed first a rockslide phase followed by a rock avalanche (sturzstrom), which led to the formation of toma in the distal area. All landslides detached from the western flank of the valley, whereas the eastern slopes are predominantly characterized by slow, deep-seated gravitational slope deformation (DSGSD). The most recent significant mass wasting was caused by rockfalls and catastrophic debris flows.