The chemical composition of glacial melt water ponds and streams on the McMurdo Ice Shelf, Antarctica
Melt waters cover c. 20% of the McMurdo Ice Shelf during the austral summer. The streams, ponds, and lakes up to 10 4 m 2 in area occur in two types of terrain systems with differing morphological, chemical, and biological characteristics: pinnacled ice (PI) areas with sparse sediment cover, low rel...
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Cambridge University Press (CUP)
1994
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Online Access: | http://dx.doi.org/10.1017/s0954102094000039 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102094000039 |
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crcambridgeupr:10.1017/s0954102094000039 2024-03-03T08:38:18+00:00 The chemical composition of glacial melt water ponds and streams on the McMurdo Ice Shelf, Antarctica Mora, S. J. De Whitehead, R. F. Gregory, M. 1994 http://dx.doi.org/10.1017/s0954102094000039 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102094000039 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Antarctic Science volume 6, issue 1, page 17-27 ISSN 0954-1020 1365-2079 Geology Ecology, Evolution, Behavior and Systematics Oceanography journal-article 1994 crcambridgeupr https://doi.org/10.1017/s0954102094000039 2024-02-08T08:36:25Z Melt waters cover c. 20% of the McMurdo Ice Shelf during the austral summer. The streams, ponds, and lakes up to 10 4 m 2 in area occur in two types of terrain systems with differing morphological, chemical, and biological characteristics: pinnacled ice (PI) areas with sparse sediment cover, low relief, and little biomass; and ice-cored moraine (ICM) areas with 10–20 cm sediment cover, hummocky topography with up to 20 m relief, occasional mirabilite deposits, and dense benthic cyanobacterial mats. Pond water composition in the two areas is markedly different. PI area melt waters have low salinities, <2270 mg 1 −1 total dissolved salts (TDS), and near neutral pH, mean = 7.8. The chemical composition of PI waters closely follows that of diluted sea water, suggesting that the release of ions from the sea ice matrix of the ice shelf is the major solute source. In contrast, ICM area melt waters have a wide range of salinities, up to 60 400 mg 1 −1 TDS and alkaline pH, mean = 9.3. The chemical composition in c. 40% of the ICM ponds investigated did not resemble that of sea water, but had higher relative abundances of SO 2− 4 , Na + , K + and Ca 2+ . Leaching of local salt deposits, particularly mirabilite, weathering of surficial sediments, and morphological features promoting closed-basin brine evolution are possible contributing factors to the enrichments. Article in Journal/Newspaper Antarc* Antarctic Science Antarctica Ice Shelf McMurdo Ice Shelf Sea ice Cambridge University Press Austral McMurdo Ice Shelf ENVELOPE(166.500,166.500,-78.000,-78.000) Antarctic Science 6 1 17 27 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Geology Ecology, Evolution, Behavior and Systematics Oceanography |
spellingShingle |
Geology Ecology, Evolution, Behavior and Systematics Oceanography Mora, S. J. De Whitehead, R. F. Gregory, M. The chemical composition of glacial melt water ponds and streams on the McMurdo Ice Shelf, Antarctica |
topic_facet |
Geology Ecology, Evolution, Behavior and Systematics Oceanography |
description |
Melt waters cover c. 20% of the McMurdo Ice Shelf during the austral summer. The streams, ponds, and lakes up to 10 4 m 2 in area occur in two types of terrain systems with differing morphological, chemical, and biological characteristics: pinnacled ice (PI) areas with sparse sediment cover, low relief, and little biomass; and ice-cored moraine (ICM) areas with 10–20 cm sediment cover, hummocky topography with up to 20 m relief, occasional mirabilite deposits, and dense benthic cyanobacterial mats. Pond water composition in the two areas is markedly different. PI area melt waters have low salinities, <2270 mg 1 −1 total dissolved salts (TDS), and near neutral pH, mean = 7.8. The chemical composition of PI waters closely follows that of diluted sea water, suggesting that the release of ions from the sea ice matrix of the ice shelf is the major solute source. In contrast, ICM area melt waters have a wide range of salinities, up to 60 400 mg 1 −1 TDS and alkaline pH, mean = 9.3. The chemical composition in c. 40% of the ICM ponds investigated did not resemble that of sea water, but had higher relative abundances of SO 2− 4 , Na + , K + and Ca 2+ . Leaching of local salt deposits, particularly mirabilite, weathering of surficial sediments, and morphological features promoting closed-basin brine evolution are possible contributing factors to the enrichments. |
format |
Article in Journal/Newspaper |
author |
Mora, S. J. De Whitehead, R. F. Gregory, M. |
author_facet |
Mora, S. J. De Whitehead, R. F. Gregory, M. |
author_sort |
Mora, S. J. De |
title |
The chemical composition of glacial melt water ponds and streams on the McMurdo Ice Shelf, Antarctica |
title_short |
The chemical composition of glacial melt water ponds and streams on the McMurdo Ice Shelf, Antarctica |
title_full |
The chemical composition of glacial melt water ponds and streams on the McMurdo Ice Shelf, Antarctica |
title_fullStr |
The chemical composition of glacial melt water ponds and streams on the McMurdo Ice Shelf, Antarctica |
title_full_unstemmed |
The chemical composition of glacial melt water ponds and streams on the McMurdo Ice Shelf, Antarctica |
title_sort |
chemical composition of glacial melt water ponds and streams on the mcmurdo ice shelf, antarctica |
publisher |
Cambridge University Press (CUP) |
publishDate |
1994 |
url |
http://dx.doi.org/10.1017/s0954102094000039 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102094000039 |
long_lat |
ENVELOPE(166.500,166.500,-78.000,-78.000) |
geographic |
Austral McMurdo Ice Shelf |
geographic_facet |
Austral McMurdo Ice Shelf |
genre |
Antarc* Antarctic Science Antarctica Ice Shelf McMurdo Ice Shelf Sea ice |
genre_facet |
Antarc* Antarctic Science Antarctica Ice Shelf McMurdo Ice Shelf Sea ice |
op_source |
Antarctic Science volume 6, issue 1, page 17-27 ISSN 0954-1020 1365-2079 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s0954102094000039 |
container_title |
Antarctic Science |
container_volume |
6 |
container_issue |
1 |
container_start_page |
17 |
op_container_end_page |
27 |
_version_ |
1792506445715996672 |