Sedimentology, structural characteristics and morphology of a Neoglacial high-Arctic moraine-mound complex: Midre Lovenbreen, Svalbard

摘要

Detailed analyses of the sediments, structural characteristics and morphology of a Neoglacial moraine-mound complex at a high-Arctic, polythermal, land-based glacier - midre Lovenbreen, Svalbard –have been undertaken in order to evaluate their mode of formation and subsequent modification.Ten moraine mound lithofacies were identified: four types of diamicton, four types of gravel, sandand mud. A buried debris-bearing basal ice facies was also identified following excavation of a singlemoraine mound. The moraine mound lithofacies and buried basal ice reflect subglacial, glaciofluvialand basal ice layer processes. Structural attributes of the moraine mounds include faulting, foldingand shearing. Three broad moraine mound morphological types are identified and characterised usingDigital Elevation Models. Moraine mound formation is linked to elevation of sediment within the ice,associated with englacial thrusting. The recognition of buried ice in a moraine mound implies thaton melting, the landform will become degraded. Hence the preservation potential of thrust-relatedfeatures within these moraine mounds is low, unless the debris content of the ice is high.