Processes controlling the development of talus slopes in SW Spitsbergen: The role of deglaciation and periglacial conditions

Abstract

The location of Svalbard at the interface between the warm Atlantic and cold Arctic oceans causes the terrestrial environment to be highly sensitive to contemporary climate warming. Talus slopes provide a component of glaciated areas that has been registering these changes on a scale of several thousand years. However, knowledge about their development during glacial recession is still limited. This paper fills this gap by providing unique data obtained by geophysical methods: electrical resistivity tomography (ERT) and ground-penetrating radar (GPR), regarding the talus slopes in Revdalen (SW Spitsbergen), which was last glaciated in the Neoglacial period. The results indicate that the thickness of talus slopes depends first of all on the size of the sediment supply area and only secondarily on the stage of development. The initial content of buried glacial ice in the talus deposits is differential and depends on both the rate of deglaciation and the local intensity of rock wall denudation. Over time, as a result of creep, the presence of massive ice is limited to ever lower parts of the slope. Above, there is aggradation of pore ice in delivered debris material. At the end of this stage, the buried glacial ice can form, or co-create together with pore ice, the core of subslope rock glaciers. The relatively long period since the beginning of the Revdalen deglaciation allowed a general model of the development of talus slopes in the polar environment to be prepared.

The Thickness of Talus Deposits in the Periglacial Area of SW Spitsbergen (Fugleberget Mountainside) in the Light of Slope Development Theories

“…The thickness of the taluses is in line with the results obtained by [46,47] on the slopes on the eastern side of Fugleberget (20-25 m) and the western slope of Fannytoppen (30-35 m) and is a slightly thinner (8-20 m) than taluses of Revdalen [48]. The active nowadays talus slopes are thicker, which may be related to the different times of talus development initiation due to the progressive deglaciation in the Hornsund region [48]. The thickness and activity of the Fugleberget talus slopes increase eastwards in the direction of deglaciation in the Holocene 3500-2000 years BP [49].…”

“…By analyzing the transverse and longitudinal views of the profiles and applying variable setting parameters of the measuring device, repeated reflection horizons were obtained at maximum depths of 25-30 m in the area of maximum debris accumulation in the central section of the "active" cones "Talus II" and "Talus III", and at a depth of about 15 m on the "stabilized" "Talus IV". The thickness of the taluses is in line with the results obtained by [46,47] on the slopes on the eastern side of Fugleberget (20-25 m) and the western slope of Fannytoppen (30-35 m) and is a slightly thinner (8-20 m) than taluses of Revdalen [48]. The active nowadays talus slopes are thicker, which may be related to the different times of talus development initiation due to the progressive deglaciation in the Hornsund region [48].…”

Spatial and temporal patterns of near‐surface ground temperature in the Arctic mountain catchment

“…Such situations were already found during previous ERT (Kasprzak, 2020) and seismic measurements (Majda nski et al, 2022). Deep water penetration is favoured by the coarsegrained material of the taluses deposited here (Senderak et al, 2021).…”

Polish Polar Research

“…GPR is one of the most useful tools in cryospheric studies (Farbrot et al 2005;Baelum 2007;Bernard et al 2014;Senderak et al 2021). Data processing was conducted using RadExplorer software.…”