Hørbyebreen polythermal glacial landsystem, Svalbard

• Main Authors: David Evans, Mateusz Strzelecki, David Milledge, Chris Orton
• Format: Article in Journal/Newspaper
• Language: unknown
• Subjects: Ferdinandbreen; Petuniabukta; Svalbard; Svenbreen
• Online Access: http://hdl.handle.net/10.1080/17445647.2012.680776

A contoured surficial geology and geomorphology map of the forelands of the Hørbyebreen, Svenbreen and Ferdinandbreen valley glaciers in Petuniabukta, Svalbard was compiled from an orthophotograph based upon aerial photographs taken in 2009. The map reveals typical polythermal glacial landsystems, comprising ice-cored latero-frontal moraine arcs grading up valley into fluted till surfaces draped by supraglacially-derived longitudinal debris stripes. The additional occurrence on the Hørbyebreen foreland of linear esker and debris ridges arranged in a geometric ridge network is thought to be related to the infilling of densely spaced crevasses, created during a period of elevated meltwater pressures and ice hydrofracturing. These landforms were associated either with a jökulhlaup that was blocked by the frozen snout or an historical surge. The Hørbyebreen landform assemblage therefore constitutes an analogue for either: (1) spatial and temporal landsystem overprinting (polythermal and surging activity); or (2) a more refined polythermal landsystem in which the build up and release of meltwater reservoirs in warm-based interiors of polythermal glaciers give rise to a particularly diagnostic landform at the up-ice junction with the cold-based snout.