WEATHERING, RADIOGENIC ISOTOPES, AND MARINE RECORDS OF GLACIAL DYNAMICS
Glacial advance and retreat is related to numerous climate system feedbacks; yet, this dynamic glacial activity tends to erase its own terrestrial record. As a result, deep-sea sediments may be the best archives for studying past glacial processes. Interpretations of these archives depend on underst...
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ftuninebromaha:oai:digitalcommons.unomaha.edu:geoggeolfacproc-1005 2024-02-11T10:04:27+01:00 WEATHERING, RADIOGENIC ISOTOPES, AND MARINE RECORDS OF GLACIAL DYNAMICS Martin, Ellen Deuerling, Kelly M. Flynn, Shauna Everhart, Cheyenne Martin, Jonathan Pain, Andrea An, Emily 2021-10-11T07:00:00Z https://digitalcommons.unomaha.edu/geoggeolfacproc/11 https://gsa.confex.com/gsa/2021AM/videogateway.cgi/id/4268?recordingid=4268 https://digitalcommons.unomaha.edu/context/geoggeolfacproc/article/1005/filename/0/type/additional/viewcontent/WEATHERING__RADIOGENIC_ISOTOPES__AND_MARINE_RECORDS_OF_GLACIAL_DYNAMICS__GSA_Connects_2021_in_Portland__Oregon_.pdf unknown DigitalCommons@UNO https://digitalcommons.unomaha.edu/geoggeolfacproc/11 https://gsa.confex.com/gsa/2021AM/videogateway.cgi/id/4268?recordingid=4268 https://digitalcommons.unomaha.edu/context/geoggeolfacproc/article/1005/filename/0/type/additional/viewcontent/WEATHERING__RADIOGENIC_ISOTOPES__AND_MARINE_RECORDS_OF_GLACIAL_DYNAMICS__GSA_Connects_2021_in_Portland__Oregon_.pdf Geography and Geology Faculty Proceedings & Presentations text 2021 ftuninebromaha 2024-01-14T17:40:48Z Glacial advance and retreat is related to numerous climate system feedbacks; yet, this dynamic glacial activity tends to erase its own terrestrial record. As a result, deep-sea sediments may be the best archives for studying past glacial processes. Interpretations of these archives depend on understanding terrestrial sources to the marine sediments. Systematic spatial variations in dissolved riverine and soil leachate Sr, Nd and Pb isotopes across an ~175 km transect from the Greenland Ice Sheet to the coast present an analog for temporal changes during glacial retreat. Specifically, the offset between dissolved (riverine or soil leachates) and bulk sediment (bedload or leached soil) isotopes is highest in young glacial sediments close to the ice sheet and approaches zero in 10 ky old glacial sediments at the coast. This difference is attributed to a transition from preferential chemical weathering of trace minerals and/or radiation damaged sites in freshly comminuted, ice-proximal sediments to predominant weathering of less radiogenic (Sr and Pb) and more radiogenic (Nd) isotopes from bulk major minerals in more extensively weathered coastal material. These isotopes are transported to the ocean where the residence time of Sr is too long to be an effective tracer of local or regional glacial processes; however, the short residence time of Pb makes it an excellent tracer of local chemical weathering processes and the intermediate residence time of Nd allows application to region studies. Data from IODP Sites 1302/3 (3550 m water depth) in the NW Atlantic illustrate that seawater Pb and Nd isotopes preserved in authigenic FeMn-oxide coatings respond dramatically to retreat of the Laurentide Ice Sheet during the penultimate glacial termination (T2; 135-129 ka) and to rapid variations during Dansgaard-Oeschger cycles. These data suggest deep-sea radiogenic isotopes preserve a more detailed record of the long term history of ice sheet dynamics than terrestrial proxies. The systematic variation in chemical weathering ... Text Greenland Ice Sheet University of Nebraska Omaha: DigitalCommons@UNO Greenland |
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Open Polar |
collection |
University of Nebraska Omaha: DigitalCommons@UNO |
op_collection_id |
ftuninebromaha |
language |
unknown |
description |
Glacial advance and retreat is related to numerous climate system feedbacks; yet, this dynamic glacial activity tends to erase its own terrestrial record. As a result, deep-sea sediments may be the best archives for studying past glacial processes. Interpretations of these archives depend on understanding terrestrial sources to the marine sediments. Systematic spatial variations in dissolved riverine and soil leachate Sr, Nd and Pb isotopes across an ~175 km transect from the Greenland Ice Sheet to the coast present an analog for temporal changes during glacial retreat. Specifically, the offset between dissolved (riverine or soil leachates) and bulk sediment (bedload or leached soil) isotopes is highest in young glacial sediments close to the ice sheet and approaches zero in 10 ky old glacial sediments at the coast. This difference is attributed to a transition from preferential chemical weathering of trace minerals and/or radiation damaged sites in freshly comminuted, ice-proximal sediments to predominant weathering of less radiogenic (Sr and Pb) and more radiogenic (Nd) isotopes from bulk major minerals in more extensively weathered coastal material. These isotopes are transported to the ocean where the residence time of Sr is too long to be an effective tracer of local or regional glacial processes; however, the short residence time of Pb makes it an excellent tracer of local chemical weathering processes and the intermediate residence time of Nd allows application to region studies. Data from IODP Sites 1302/3 (3550 m water depth) in the NW Atlantic illustrate that seawater Pb and Nd isotopes preserved in authigenic FeMn-oxide coatings respond dramatically to retreat of the Laurentide Ice Sheet during the penultimate glacial termination (T2; 135-129 ka) and to rapid variations during Dansgaard-Oeschger cycles. These data suggest deep-sea radiogenic isotopes preserve a more detailed record of the long term history of ice sheet dynamics than terrestrial proxies. The systematic variation in chemical weathering ... |
format |
Text |
author |
Martin, Ellen Deuerling, Kelly M. Flynn, Shauna Everhart, Cheyenne Martin, Jonathan Pain, Andrea An, Emily |
spellingShingle |
Martin, Ellen Deuerling, Kelly M. Flynn, Shauna Everhart, Cheyenne Martin, Jonathan Pain, Andrea An, Emily WEATHERING, RADIOGENIC ISOTOPES, AND MARINE RECORDS OF GLACIAL DYNAMICS |
author_facet |
Martin, Ellen Deuerling, Kelly M. Flynn, Shauna Everhart, Cheyenne Martin, Jonathan Pain, Andrea An, Emily |
author_sort |
Martin, Ellen |
title |
WEATHERING, RADIOGENIC ISOTOPES, AND MARINE RECORDS OF GLACIAL DYNAMICS |
title_short |
WEATHERING, RADIOGENIC ISOTOPES, AND MARINE RECORDS OF GLACIAL DYNAMICS |
title_full |
WEATHERING, RADIOGENIC ISOTOPES, AND MARINE RECORDS OF GLACIAL DYNAMICS |
title_fullStr |
WEATHERING, RADIOGENIC ISOTOPES, AND MARINE RECORDS OF GLACIAL DYNAMICS |
title_full_unstemmed |
WEATHERING, RADIOGENIC ISOTOPES, AND MARINE RECORDS OF GLACIAL DYNAMICS |
title_sort |
weathering, radiogenic isotopes, and marine records of glacial dynamics |
publisher |
DigitalCommons@UNO |
publishDate |
2021 |
url |
https://digitalcommons.unomaha.edu/geoggeolfacproc/11 https://gsa.confex.com/gsa/2021AM/videogateway.cgi/id/4268?recordingid=4268 https://digitalcommons.unomaha.edu/context/geoggeolfacproc/article/1005/filename/0/type/additional/viewcontent/WEATHERING__RADIOGENIC_ISOTOPES__AND_MARINE_RECORDS_OF_GLACIAL_DYNAMICS__GSA_Connects_2021_in_Portland__Oregon_.pdf |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_source |
Geography and Geology Faculty Proceedings & Presentations |
op_relation |
https://digitalcommons.unomaha.edu/geoggeolfacproc/11 https://gsa.confex.com/gsa/2021AM/videogateway.cgi/id/4268?recordingid=4268 https://digitalcommons.unomaha.edu/context/geoggeolfacproc/article/1005/filename/0/type/additional/viewcontent/WEATHERING__RADIOGENIC_ISOTOPES__AND_MARINE_RECORDS_OF_GLACIAL_DYNAMICS__GSA_Connects_2021_in_Portland__Oregon_.pdf |
_version_ |
1790601055163121664 |