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标题：Formation processes of basal ice at Hamna Glacier, Sôya Coast, East Antarctica, inferred by detailed co-isotopic analyses
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作者：Yoshinori Iizuka ; Hiroshi Satake ; Takayuki Shiraiwa 等
期刊名称：Journal of Glaciology
印刷版ISSN：0022-1430
电子版ISSN：1727-5652
出版年度：2001
卷号：47
期号：157
页码：223-231
DOI：10.3189/172756501781832359
出版社：Cambridge University Press
摘要：Debris-laden basal ice is exposed along an ice cliff near Hamna Glacier, Sôya Coast, East Antarctica. The basal ice is about 6.8 m thick and shows conspicuous stratigraphic features. The upper 5.5 m consists of alternating layers of bubble-free and bubbly ice. δ values of the bubble-free ice layers are enriched by 2.4 ±1.0‰ (standard deviation) for δ 18 O compared to values of neighboring bubbly ice layers above, and slopes of δ 18 O vs δ D are close to 8. Such layers are suggested to have been formed by refreezing of meltwater in an open system. In contrast, part of the bubbly ice layers shows neutral profiles for stable isotopes, suggesting that these ice masses are undisturbed ice-sheet ice which was not affected by melting and freezing. The massive alternating layers are thus considered to have been formed by folding of refrozen and non-melted layers. The lower 1.3 m consists predominantly of bubble-free massive ice. The profile of co-isotopic values shows a change of about 3.0‰ for δ 18 O at the interface between bubble-free and bubbly ice. Since the isotopic change occurred over a wider thickness than the upper 5.5 m, the basal ice is suggested to have been formed by refreezing of meltwater on a larger scale than the upper 5.5 m.