Chemical weathering in a moraine at the ice sheet margin at Kangerlussuaq, western Greenland
Weathering caused by interaction between glacial sediments and water in exposed moraines needs to be studied to evaluate their possible effects on the global carbon cycle. In this study, moraine ponds, moraine porewaters, and till samples were collected at a moraine adjacent to the Greenland Ice She...
Published in: | Arctic, Antarctic, and Alpine Research |
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Taylor & Francis Group
2019
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Online Access: | https://doi.org/10.1080/15230430.2019.1660125 https://doaj.org/article/928fcc854a664bd5b380b25fb4642c2f |
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fttriple:oai:gotriple.eu:oai:doaj.org/article:928fcc854a664bd5b380b25fb4642c2f 2023-05-15T14:14:24+02:00 Chemical weathering in a moraine at the ice sheet margin at Kangerlussuaq, western Greenland L. F. Auqué I. Puigdomenech E.-L. Tullborg M. J. Gimeno K. Grodzinsky K. J. Hogmalm 2019-01-01 https://doi.org/10.1080/15230430.2019.1660125 https://doaj.org/article/928fcc854a664bd5b380b25fb4642c2f en eng Taylor & Francis Group 1523-0430 1938-4246 doi:10.1080/15230430.2019.1660125 https://doaj.org/article/928fcc854a664bd5b380b25fb4642c2f undefined Arctic, Antarctic, and Alpine Research, Vol 51, Iss 1, Pp 440-459 (2019) chemical weathering till moraine isotope geochemistry greenland geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2019 fttriple https://doi.org/10.1080/15230430.2019.1660125 2023-01-22T19:35:21Z Weathering caused by interaction between glacial sediments and water in exposed moraines needs to be studied to evaluate their possible effects on the global carbon cycle. In this study, moraine ponds, moraine porewaters, and till samples were collected at a moraine adjacent to the Greenland Ice Sheet at Kangerlussuaq. Scanning electron microscopy (SEM) studies of the till show limited evidence of silicate chemical weathering, but the moraine waters have substantial solute concentrations. δ34SSO4 and δ18OSO4 data indicate that the origin of dissolved sulfate is the oxidation of sulfides, in agreement with the SEM observations. The dissolved HCO3−/SO42− molar ratios indicate an uneven balance between sulfuric and carbonic acid weathering; C-isotope data indicate that some of the CO2 originates from organic carbon mineralization. Ion–ion plots provide evidence of carbonate weathering and of the formation of secondary gypsum and calcite through evaporation and (or) cryoconcentration. The 87Sr/86Sr ratios in the waters correlate with the corresponding till samples, supporting the local origin of the dissolved strontium, which is higher in the waters than in the till due to the selective weathering of biotite. The data evidence a large degree of chemical weathering in moraines promoted by large rock–water ratios and by the hydraulic isolation created by the frozen till. The high PCO2 in the studied moraine waters indicates that they may represent a previously underestimated CO2 source. Article in Journal/Newspaper Antarctic and Alpine Research Arctic Carbonic acid Greenland Ice Sheet Kangerlussuaq Unknown Greenland Kangerlussuaq ENVELOPE(-55.633,-55.633,72.633,72.633) Arctic, Antarctic, and Alpine Research 51 1 440 459 |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
fttriple |
language |
English |
topic |
chemical weathering till moraine isotope geochemistry greenland geo envir |
spellingShingle |
chemical weathering till moraine isotope geochemistry greenland geo envir L. F. Auqué I. Puigdomenech E.-L. Tullborg M. J. Gimeno K. Grodzinsky K. J. Hogmalm Chemical weathering in a moraine at the ice sheet margin at Kangerlussuaq, western Greenland |
topic_facet |
chemical weathering till moraine isotope geochemistry greenland geo envir |
description |
Weathering caused by interaction between glacial sediments and water in exposed moraines needs to be studied to evaluate their possible effects on the global carbon cycle. In this study, moraine ponds, moraine porewaters, and till samples were collected at a moraine adjacent to the Greenland Ice Sheet at Kangerlussuaq. Scanning electron microscopy (SEM) studies of the till show limited evidence of silicate chemical weathering, but the moraine waters have substantial solute concentrations. δ34SSO4 and δ18OSO4 data indicate that the origin of dissolved sulfate is the oxidation of sulfides, in agreement with the SEM observations. The dissolved HCO3−/SO42− molar ratios indicate an uneven balance between sulfuric and carbonic acid weathering; C-isotope data indicate that some of the CO2 originates from organic carbon mineralization. Ion–ion plots provide evidence of carbonate weathering and of the formation of secondary gypsum and calcite through evaporation and (or) cryoconcentration. The 87Sr/86Sr ratios in the waters correlate with the corresponding till samples, supporting the local origin of the dissolved strontium, which is higher in the waters than in the till due to the selective weathering of biotite. The data evidence a large degree of chemical weathering in moraines promoted by large rock–water ratios and by the hydraulic isolation created by the frozen till. The high PCO2 in the studied moraine waters indicates that they may represent a previously underestimated CO2 source. |
format |
Article in Journal/Newspaper |
author |
L. F. Auqué I. Puigdomenech E.-L. Tullborg M. J. Gimeno K. Grodzinsky K. J. Hogmalm |
author_facet |
L. F. Auqué I. Puigdomenech E.-L. Tullborg M. J. Gimeno K. Grodzinsky K. J. Hogmalm |
author_sort |
L. F. Auqué |
title |
Chemical weathering in a moraine at the ice sheet margin at Kangerlussuaq, western Greenland |
title_short |
Chemical weathering in a moraine at the ice sheet margin at Kangerlussuaq, western Greenland |
title_full |
Chemical weathering in a moraine at the ice sheet margin at Kangerlussuaq, western Greenland |
title_fullStr |
Chemical weathering in a moraine at the ice sheet margin at Kangerlussuaq, western Greenland |
title_full_unstemmed |
Chemical weathering in a moraine at the ice sheet margin at Kangerlussuaq, western Greenland |
title_sort |
chemical weathering in a moraine at the ice sheet margin at kangerlussuaq, western greenland |
publisher |
Taylor & Francis Group |
publishDate |
2019 |
url |
https://doi.org/10.1080/15230430.2019.1660125 https://doaj.org/article/928fcc854a664bd5b380b25fb4642c2f |
long_lat |
ENVELOPE(-55.633,-55.633,72.633,72.633) |
geographic |
Greenland Kangerlussuaq |
geographic_facet |
Greenland Kangerlussuaq |
genre |
Antarctic and Alpine Research Arctic Carbonic acid Greenland Ice Sheet Kangerlussuaq |
genre_facet |
Antarctic and Alpine Research Arctic Carbonic acid Greenland Ice Sheet Kangerlussuaq |
op_source |
Arctic, Antarctic, and Alpine Research, Vol 51, Iss 1, Pp 440-459 (2019) |
op_relation |
1523-0430 1938-4246 doi:10.1080/15230430.2019.1660125 https://doaj.org/article/928fcc854a664bd5b380b25fb4642c2f |
op_rights |
undefined |
op_doi |
https://doi.org/10.1080/15230430.2019.1660125 |
container_title |
Arctic, Antarctic, and Alpine Research |
container_volume |
51 |
container_issue |
1 |
container_start_page |
440 |
op_container_end_page |
459 |
_version_ |
1766286879980781568 |