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The glacial geomorphology between the lakes Vänern and Vättern is presented on a 1:220,000 scale, LiDAR-based map covering approximately 18,000 km2. Fifteen landform units have been mapped; end moraines, De Geer moraines, drumlins, crag-and-tails, hummock tracts and corridors, irregular ridges, murtoos, eskers, deltas/sandur, outwash complexes, meltwater channels, boulder bars/sheets, the Timmersdala ridge, raised shorelines, sand dunes and prominent landslide scars (the last three are post-glacial). The area includes moraines associated with the Younger Dryas cold interval and drainage deposits of the Baltic Ice Lake. Additionally, the map reveals previously undetected geomorphic features including (1) murtoos, (2) abundant traces of meltwater erosion manifested as channels and hummock corridors, (3) laterally extensive end-moraine systems (the Remmene and Kungslena ice-margin positions) and (4) the distinct lobate shape of end moraines formed above the highest shoreline. This map provides a uniform base for future use in georesources, paleo ice-sheet modelling, geologic history, and geoconservation. [ABSTRACT FROM AUTHOR]

High-resolution digital elevation models of Finland and Sweden based on LiDAR (Light Detection and Ranging) reveal subglacial landforms in great detail. We describe the ice-sheet scale distribution and morphometric characteristics of a glacial landform that is distinctive in morphology and occurs commonly in the central parts of the former Scandinavian Ice Sheet, especially up-ice of the Younger Dryas end moraine zone. We refer to these triangular or V-shaped landforms as murtoos (singular, 'murtoo'). Murtoos are typically 30–200 m in length and 30–200 m in width with a relief of commonly <5 m. Murtoos have straight and steep edges, a triangular tip oriented parallel to ice-flow direction, and an asymmetric longitudinal profile with a shorter, but steeper down-ice slope. The spatial distribution of murtoos and their geomorphic relation to other landforms indicate that they formed subglacially during times of climate warming and rapid retreat of the Scandinavian Ice Sheet when large amounts of meltwater were delivered to the bed. Murtoos are formed under warm-based ice and may be associated with a non-channelized subglacial hydraulic system that evacuated large discharges of subglacial water. [ABSTRACT FROM AUTHOR]

The article discusses the use of the light detection and ranging (LiDAR) technology in observations and advancements in geomorphic theory. Topics discussed include landforms that can easily be detected by LiDAR on aerial photographs, opportunities presented by LiDAR in the study of geomorphic expression of structure and advantages associated with LiDAR use as seen in Scandinavia including a quicker and cost-efficient process.

We present a 1:100,000 scale Quaternary geomorphic map covering 2500 km2in Central Sweden and including the Siljan Impact Structure. Because of the crater, the area is currently under consideration to become a geopark, and this project was undertaken to document Quaternary geology that may be of interest to park organizers and future visitors. A high-resolution digital elevation model with a vertical resolution of 0.25 m and a lateral resolution of 2.0 m was used as the base to map sub-, pro-, and post-glacial landforms. Consideration of the suite of landforms indicates ice flow from the northwest, multiple paleo-lake levels, and unstable landscapes into the Holocene. Additionally, the impact structure has played a role in routing both glacial and post-glacial drainage. [ABSTRACT FROM AUTHOR]