Abstract

Antarctic ice shelves are the floating extensions of the continental ice sheet into the ocean, buttressing the flow of inland, grounded ice from the continent’s interior. Over 50% of the Antarctic margin is fringed by such ice shelves, which are formed of alternating bands of meteoric glacier and suture zone ice. Suture zone ice is softer and fractures less easily than meteoric ice – understanding the structure and mechanical state of ice shelves is crucial to assessment of their vulnerability to thinning, rift propagation, and potential disintegration. In this talk, I will present field observations from three ice shelves around Antarctica (Larsen C, Shackleton, and McMurdo): optical televiewer imaging of the interior of hot-water drilled boreholes to infer ice structure; ground-penetrating radar surveys informing on the extent of brine infiltration; and observations of firn saturation and near-surface refrozen melt layers, concluding with implications for more widespread ice slab presence and formation.