ANNEALING RECRYSTALLIZATION IN LABORATORY AND NATURALLY DEFORMED ICE

• Main Authors: Gow, A., Sheehy, W.
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 1987
• Subjects: [PHYS.HIST]Physics [physics]/Physics archives; Antarctic; The Antarctic; Antarc*; Antarctica; Ice Sheet
• Online Access: https://hal.science/jpa-00226284; https://hal.science/jpa-00226284/document; https://hal.science/jpa-00226284/file/ajp-jphyscol198748C138.pdf; https://doi.org/10.1051/jphyscol:1987138

Results are presented of annealing recrystallization in both naturally and laboratory deformed ice. Thin section techniques were used to follow the progress of recrystallization which, in the case of highly compressed ice pellets annealed at -3°C, showed that as soon as any new crystal was nucleated in the deformed ice matrix its retained its lattice orientation over the duration of the recrystallization. Laboratory annealing at ambient pressures of highly deformed, strongly oriented crystal ice from cores deep in the Antarctic Ice Sheet resulted in growth of very large crystals exhibiting c-axis orientations very much degraded with respect to the original ice. Textures and fabrics of the same ice annealed at 200 bars confining pressure closely resembled those observed in ice undergoing dynamic (annealing) recrystallization at 190 - 200 bars overburden pressure near the base of the ice sheet, which at this location in Antarctica was at pressure melting.