Physical and chemical investigations on ice cores from the Filchner-Ronne Ice Shelf, supplement to: Graf, Wolfgang; Moser, Heribert; Reinwarth, Oskar; Kipfstuhl, Sepp; Oerter, Hans; Minikin, Andreas; Wagenbach, Dietmar (1994): Snow-accumulation rates and isotopic content (2H, 3H) of near-surface firn from the Filchner-Ronne Ice Shelf, Antarctica. Annals of Glaciology, 20, 121-128
The accumulation and distribution of the 2H content of near-surface layers in the eastern part of the Ronne Ice Shelf were determined from 16 firn cores drilled to about 10 m depth during the Filchner IIIa and IV campaigns in 1990 and 1992, respectively. The cores were dated stratigraphically by sea...
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| Format: | Article in Journal/Newspaper |
| Language: | English |
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PANGAEA - Data Publisher for Earth & Environmental Science
2006
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| Subjects: | |
| Online Access: | https://dx.doi.org/10.1594/pangaea.548753 https://doi.pangaea.de/10.1594/PANGAEA.548753 |
| Summary: | The accumulation and distribution of the 2H content of near-surface layers in the eastern part of the Ronne Ice Shelf were determined from 16 firn cores drilled to about 10 m depth during the Filchner IIIa and IV campaigns in 1990 and 1992, respectively. The cores were dated stratigraphically by seasonal d2H variations in the firn. In addition, 3H and high-resolution chemical profiles were used to assist in dating. Both the accumulation rate and the stable-isotope content decrease with increasing distance from the ice edge: the d2H values range from about -195 per mil at the ice edge to -250 per mil at BAS sites 5 and 6, south of Henry Ice Rise, and the accumulation rates from about 210 to 90 kg/m**2/a. The d2H values of the near-surface firn and the 10 m firn temperatures (Theta) at individual sites are very well correlated: ddelta2H/dTheta=(10.3±0.6)per mil /K; r = 0.97.The d2H profiles of the two ice cores B13 and B15 drilled in 1990 and 1992 to 215 and 320 m depth, respectively, reflect the gradual depletion in 2H in the firn upstream of the drill sites. Comparison with tlie surface data indicates that the ice above 142 m in core B15 and above 137 m in core B13 was deposited on the ice shelf, whereas the deeper ice, down to 152.8 m depth, most probably originated from the margin of the Antarctic ice sheet. |
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