Glacial and periglacial geomorphology of central Troms and Finnmark county, Arctic Norway

Abstract

Here we present a glacial and periglacial geomorphological map of a ∼6800 km 2 region of central Troms and Finnmark county, Arctic Norway. The map is presented at a 1:115,000 scale with the aim of characterising the spatial distribution of glacial and periglacial landforms and facilitating the reconstruction of the glacial history of the region during the latter stages of deglaciation from the Last Glacial Maximum and into the Holocene. Mapping was conducted predominantly by manual digitisation of landforms using a combination of Sentinel-2A/2B satellite imagery (10 m pixel resolution), vertical aerial photographs (<1 m pixel resolution), and Digital Elevation Models (10 and 2 m pixel resolution). Over 20,000 individual features have been mapped and include moraines (subdivided into major and minor moraines), ridges within areas of discrete debris accumulations (DDAs), flutings, eskers, irregular mounded terrain, lineations, glacially streamlined bedrock, possible glacially streamlined terrain, pronival ramparts, rock glaciers (subdivided into valley wall and valley floor, and rock glacierised moraines), lithalsas, contemporary glaciers and lakes. The map records several noteworthy large moraine assemblages within individual valleys, forming inset sequences from pre-Younger Dryas limits up to the 2018/19 ice margins and represents a valuable dataset for reconstructing Holocene glacial and periglacial activity.

Past glaciation of temperate‐continental mountains: A model for a debris‐charged plateau icefield/cirque glacier landsystem in the Southern Carpathians, Romania

“…However, their compilation in ancient settings requires the recognition of geomorphological process‐form regimes, informed by suitable modern analogues. Hence, we consulted modern analogue landsystems from similar climatic and topographic settings, such as those for plateaux (Rea et al, 1998; Rea et al, 1999; Rea & Evans, 2003, 2007) and glaciated valley (Benn et al, 2003; Benn & Owen, 2002) settings where paraglacial and periglacial process‐form regimes interact with those of glacial systems (Knight et al, 2019; Leigh et al, 2021).…”

“…Over the longer timescales of multiple Quaternary glaciations, however, RSF operation likely initiates and/or contributes to cirque development through headwall erosion into plateau surfaces (cf. Evans, 2021;Turnbull & Davies, 2006), sourcing debris for the development of rock glaciers and moraines.…”

“…Hence, we endorse the concept of equifinality of rock glaciers (Knight et al, 2019; Whalley, 2009). Additionally, we follow the conventions of Thompson (1957), Østrem (1964), England (1978), Leigh et al (2021) and Urdea et al (2022) in recognising rock‐glacierised moraines in situations where moraines appear to have been remobilized by creep, either due to interstitial pore ice accumulation or an initial glacier ice core (Table 1). In each case, rock glaciers and rock‐glacierised moraines in the study area are relict features and, hence, are genetically classified based upon their more muted appearance after de‐icing.…”

“…The spatio‐temporal relationships between the mapped landforms and the sedimentological evidence provide a clear signature of past glaciation style, debris turnover and moraine construction in the Godeanu Mountains, thereby facilitating the compilation of a glacial landsystem model for the region of the Southern Carpathians. This landsystem model displays many of the characteristics of the conceptual plateau icefield (Rea & Evans, 2003), glaciated valley (Benn et al, 2003) and the cirque/niche (Bickerdike, Ó Cofaigh, et al, 2018) glacial landsystems, as well as elements of debris‐charged geomorphology observed in a modern analogue in Norway (Leigh et al, 2021). Therefore, it is best classified as a debris‐charged plateau icefield/cirque glacier landsystem.…”

The geolocation of features on information surfaces and the use of the open and FAIR data principles in the mountain landscape domain and geoheritage

“…However, these are incomplete, either because investigations were published and accessible only after the PLoE compilation or for some reason were not included. The overview of an area in north Norway, Lyngen [69.576,20.215] provided by Leigh et al, 58 is not included in PLoE. However, Leigh et al 58…”