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Constraining the timescales of sediment transport by glacier systems is important for understanding the processes controlling sediment dynamics within glacierized catchments, and because the accumulation of supraglacial sediment influences glacier response to climate change. However, glacial sediment transport can be difficult to observe; sediment can be transported englacially, subglacially, supraglacially or at the ice margins, and may be stored temporarily on headwall slopes or within moraines before being (re‐)entrained and transported by glacier ice. This study is a proof of concept of the use of luminescence rock surface burial dating to establish rates of englacial sediment transport. Our novel approach combines luminescence rock surface burial dating of englacial clasts with an ice‐flow model that includes Lagrangian particle tracking to quantify rates of sediment transport through the Miage Glacier catchment in the Italian Alps. Luminescence rock surface burial ages for seven samples embedded in the near‐surface ice in the ablation area range from 0.0 ± 1.0 to 4.7 ± 0.3 ka and are consistent with the ice‐flow model results. Our results show that the transport durations of individual clasts vary by an order of magnitude, implying rapid clast transport near the glacier surface and longer transport histories for clasts transported lower in the ice column. In some cases, clasts were stored on the headwalls or within ice‐marginal moraines for several thousand years before being englacially transported. The results illustrate the different routes by which glaciers transport sediment and provide the first direct measurements of englacial sediment transport duration. 

Abstract The impact of late Cenozoic climate on the East Antarctic Ice Sheet is uncertain. Poorly constrained patterns of relative ice thinning and thickening impair the reconstruction of past ice-sheet dynamics and global sea-level budgets. Here we quantify long-term ice cover of mountains protruding the ice-sheet surface in western Dronning Maud Land, using cosmogenic Chlorine-36, Aluminium-26, Beryllium-10, and Neon-21 from bedrock in an inverse modeling approach. We find that near-coastal sites experienced ice burial up to 75–97% of time since 1 Ma, while interior sites only experienced brief periods of ice burial, generally <20% of time since 1 Ma. Based on these results, we suggest that the escarpment in Dronning Maud Land acts as a hinge-zone, where ice-dynamic changes driven by grounding-line migration are attenuated inland from the coastal portions of the East Antarctic Ice Sheet, and where precipitation-controlled ice-thickness variations on the polar plateau taper off towards the coast.