Subgrain boundaries and related microstructural features in EDML (Antarctica) deep ice core

• Published in: Journal of Glaciology
• Main Authors: Weikusat, Ilka, Kipfstuhl, Sepp, Faria, Sérgio H., Azuma, Nobuhiko, Miyamoto, Atsushi
• Format: Article in Journal/Newspaper
• Language: English
• Published: International Glaciological Society
• Subjects: 452; East Antarctica; Dronning Maud Land; Antarc*; Antarctica; EPICA; ice core; Journal of Glaciology
• Online Access: http://hdl.handle.net/2115/40199; https://doi.org/10.3189/002214309788816614

Subgrain boundaries revealed as shallow sublimation grooves on ice sample surfaces are a direct and easily observable feature of intracrystalline deformation and recrystallization. Statistical data obtained from the EPICA Dronning Maud Land (EDML) deep ice core drilled in East Antarctica cannot detect a depth region of increased subgrain-boundary formation. Grain-boundary morphologies show a strong influence of internal strain energy on the microstructure at all depths. The data do not support the classical view of a change of dominating recrystallization regimes with depth. Three major types of subgrain boundaries, reflecting high mechanical anisotropy, are specified in combination with crystal-orientation analysis.