Palaeofluvial and subglacial channel networks beneath Humboldt Glacier, Greenland

• Published in: Geology
• Main Authors: Livingstone, S.J., Chu, W., Ely, J.C., Kingslake, J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Geological Society of America 2017
• Subjects: Greenland; glacier; Humboldt Glacier; Ice Sheet
• Online Access: https://eprints.whiterose.ac.uk/113109/; https://eprints.whiterose.ac.uk/113109/9/Geology-2017-Livingstone-551-4.pdf; https://doi.org/10.1130/G38860.1

The identification of subglacial drainage systems can inform our understanding of past and present hydrological processes, landscape evolution, and ice dynamics. Here, we present evidence from satellite imagery, digital elevation models, and radio-echo sounding data for a series of channelized networks with contrasting paleofluvial and subglacial origins beneath Humboldt Glacier, northern Greenland. A >250-km-long, dendritic paleofluvial channel network beneath the northern portion of Humboldt is interpreted as a preglacial feature. Roughly linear channels beneath the southern portion of Humboldt, which display a similar distribution to tunnel valleys found on the beds of former ice sheets, are likely to have been eroded by subglacial meltwater routed along the ice-sheet bed. We suggest that basal meltwater is actively being routed down both the paleofluvial and subglacially formed channel networks to the coast. Inheritance of the preglacial channel network may have influenced the present-day location and dynamics of Humboldt Glacier and enhanced selective erosion at its down-glacier end.