Understanding rapid deglaciation at Mittelbergferner through a sediment-landform association lens

Glaciers in the Ötztal Alps (Austria) have been undergoing retreat since the “Little Ice Age'' in 1850, leaving a complex geomorphic record of subglacial features, glacial and fluvial deposits, and slope-derived talus. By systematically describing and studying these features in modern alpine glacial environments, we can obtain clues as to what is driving these changes and how they are responding to the current climate conditions the Earth is facing. Mittelbergferner is one of the largest glaciers in the Ötztal Alps, and also a tourist destination in the Pitztal area, where there is an extensive suite of hitherto unstudied supra- and subglacial morphotypes that require documentation and interpretation. Here, a high resolution geological-geomorphological map is presented for the East and West lobes of Mittelbergferner based on photogrammetric data, which will be the main tool for studying sediment-landform assemblages in the area. Some of the observed features include the glacio-structural framework, drainage networks, flutes, small moraines and talus slopes. There are also signs of imminent detachments from the main glacier at the West lobe, as well as exposed bedrock within the ice and associated trails of diamicton, which are indicators of decrease in accumulation and consequent retreat. Other questions arise regarding supraglacial debris, sediment distribution and the precise role that dead ice plays on sedimentary architecture during the retreat process. The analysis of the landforms associated with ice recession at Mittelbergferner will contribute to understanding the sediment dynamics operating at rapidly retreating glaciers, offer additional perspectives on processes that are occurring in comparable glaciated areas of the Austrian Alps, and possibly give insight into future ice margin stability.