Document Type

Article

Publication Date

12-11-2021

Publication Title

Journal of Glaciology

Department

Thayer School of Engineering

Additional Department

Department of Earth Sciences

Abstract

Microstructures, including crystallographic fabric, within the margin of streaming ice can exert strong control on flow dynamics. To characterize a natural setting, we retrieved three cores, two of which reached bed, from the flank of Jarvis Glacier, eastern Alaska Range, Alaska. The core sites lie ~1 km downstream of the source, with abundant water present in the extracted cores and at the base of the glacier. All cores exhibit dipping layers, a combination of debris bands and bubble-free domains. Grain sizes coarsen on average approaching the lateral margin. Crystallographic orientations are more clustered and with c-axes closer to horizontal nearer the lateral margin. The measured fabric is sufficiently weak to induce little mechanical anisotropy, but the data suggest that despite the challenging conditions of warm ice, abundant water and a short flow distance, many aspects of the microstructure, including measurable crystallographic fabric, evolved in systematic ways.

DOI

10.1017/jog.2021.62

Original Citation

Gerbi, C., Mills, S., Clavette, R., Campbell, S., Bernsen, S., Clemens-Sewall, D., . . . Hruby, K. (2021). Microstructures in a shear margin: Jarvis Glacier, Alaska. Journal of Glaciology, 67(266), 1163-1176. doi:10.1017/jog.2021.62

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