Freeze-on of Frozen Sediments

Frozen sediments are commonly adhered to the base of glaciers and ice streams but little is known regarding their spatial distribution, growth rate, and impact on glacier sliding. My collaborators and I are building upon established theoretical, experimental, and field investigations that have elucidated the central role of premelting and surface-energy effects in controlling the dynamics of frost heave in soils. We aim to provide a theoretical description and experimental validation of the role of premelting at the basal ice-sediment interface.

Our experiments involve a custom cryogenic uniaxial compression device, outfitted with electrical sensors to track the infiltration of ice into sediment through electrical resistivity tomography. We also use a cryogenic ring shear device to grow fringe during glacier slip and assess its impact on basal friction. These experiments are designed to provide quantitative insight into the impact of ice infiltration into sediments on glacier sliding, erosion, and subglacial landform evolution. By combining theory and experimentation, we hope to achieve a better understanding of these complex processes and ultimately reduce uncertainty in ice-sheet models.