Glacial landsystems of Satujökull, Iceland: A modern analogue for glacial landsystem overprinting by mountain icecaps

Mapping of the surficial geology and geomorphology of the Satujokull foreland of the northern Hofsjokull ice cap in central Iceland provides a clear signature of glacial landsystem overprinting as a result of complex glacier behaviour during the historical period. Landsystem 1 comprises a wide arc of ice-cored moraine and controlled ridges lying outside fluted and drumlinized terrain, and is indicative of polythermal conditions. This landform assemblage commonly marks the historical Little Ice Age maximum limit on the forelands of upland icefields in the arid interior of Iceland and is therefore a record of climatically driven glacier advance. Landsystem 2 contains most of the diagnostic criteria for the surging glacier landsystem and records two separate surges by the western margin of Satujokull in the period since the attainment of the Little Ice Age maximum advance. The occurrence of Landsystem 2 is significant because Satujokull has not been previously regarded as a surging glacier, even though other outlets of Hofsjokull are prone to surging. Landsystem overprinting, especially in response to changing thermal regimes and/or glacier dynamics, and particularly by different flow units in the same glacier, is rarely reported but is crucial to the critical application of modern landsystem analogues to Quaternary palaeoglaciological reconstruction.