Rock avalanche–glacier interactions and moraine-system development in Jökuldalur, Dyrfjöll, Eastern Iceland

In this paper we present a geomorphological map of the Jökuldalur valley, in the Dyrfjöll massif, in Eastern Iceland (65°31′ N, 13°57′ W; 1,134 m a.s.l.) to distinguish massive rock avalanche deposits from hummocky moraine landforms and reconstruct the geomorphological evolution of the valley. Mapping was conducted through traditional analytical approaches, including stereoscopic photointerpretation, hand-drawn landform delineation over enlarged orthophotographs, and detailed field observations. These approaches were complemented by digital techniques, including Structure-from-Motion (SfM) photogrammetry, Uncrewed Aerial Vehicle (UAV) to obtain oblique photographs, and Geographic Information System (GIS)- and Computer-Aided Design (CAD)-based digitisation. The final cartographic symbolisation was carried out in ArcGIS Pro, enabling a photorealistic 3D view. The map shows the existence of at least one rock avalanche that covers the valley, followed by a sequence of hummocky moraines, revealing six glacial advances, likely influenced by the insulating effects of avalanche debris on a pre-existing glacier.