Radiostratigraphy and age structure of the Greenland Ice Sheet
©2015. The Authors. Several decades of ice-penetrating radar surveys of the Greenland and Antarctic ice sheets have observed numerous widespread internal reflections. Analysis of this radiostratigraphy has produced valuable insights into ice sheet dynamics and motivates additional mapping of these r...
Published in: | Journal of Geophysical Research: Earth Surface |
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ftcdlib:qt4dj9r5n2 2023-05-15T13:50:54+02:00 Radiostratigraphy and age structure of the Greenland Ice Sheet Macgregor, JA Fahnestock, MA Catania, GA Paden, JD Prasad Gogineni, S Young, SK Rybarski, SC Mabrey, AN Wagman, BM Morlighem, M 2015-01-01 application/pdf http://www.escholarship.org/uc/item/4dj9r5n2 english eng eScholarship, University of California qt4dj9r5n2 http://www.escholarship.org/uc/item/4dj9r5n2 public Macgregor, JA; Fahnestock, MA; Catania, GA; Paden, JD; Prasad Gogineni, S; Young, SK; et al.(2015). Radiostratigraphy and age structure of the Greenland Ice Sheet. Journal of Geophysical Research F: Earth Surface. doi:10.1002/2014JF003215. UC Irvine: Retrieved from: http://www.escholarship.org/uc/item/4dj9r5n2 article 2015 ftcdlib https://doi.org/10.1002/2014JF003215 2018-07-13T22:54:53Z ©2015. The Authors. Several decades of ice-penetrating radar surveys of the Greenland and Antarctic ice sheets have observed numerous widespread internal reflections. Analysis of this radiostratigraphy has produced valuable insights into ice sheet dynamics and motivates additional mapping of these reflections. Here we present a comprehensive deep radiostratigraphy of the Greenland Ice Sheet from airborne deep ice-penetrating radar data collected over Greenland by The University of Kansas between 1993 and 2013. To map this radiostratigraphy efficiently, we developed new techniques for predicting reflection slope from the phase recorded by coherent radars. When integrated along track, these slope fields predict the radiostratigraphy and simplify semiautomatic reflection tracing. Core-intersecting reflections were dated using synchronized depth-age relationships for six deep ice cores. Additional reflections were dated by matching reflections between transects and by extending reflection-inferred depth-age relationships using the local effective vertical strain rate. The oldest reflections, dating to the Eemian period, are found mostly in the northern part of the ice sheet. Within the onset regions of several fast-flowing outlet glaciers and ice streams, reflections typically do not conform to the bed topography. Disrupted radiostratigraphy is also observed in a region north of the Northeast Greenland Ice Stream that is not presently flowing rapidly. Dated reflections are used to generate a gridded age volume for most of the ice sheet and also to determine the depths of key climate transitions that were not observed directly. This radiostratigraphy provides a new constraint on the dynamics and history of the Greenland Ice Sheet. Article in Journal/Newspaper Antarc* Antarctic Greenland Ice Sheet University of California: eScholarship Antarctic Greenland Journal of Geophysical Research: Earth Surface 120 2 212 241 |
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Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
English |
description |
©2015. The Authors. Several decades of ice-penetrating radar surveys of the Greenland and Antarctic ice sheets have observed numerous widespread internal reflections. Analysis of this radiostratigraphy has produced valuable insights into ice sheet dynamics and motivates additional mapping of these reflections. Here we present a comprehensive deep radiostratigraphy of the Greenland Ice Sheet from airborne deep ice-penetrating radar data collected over Greenland by The University of Kansas between 1993 and 2013. To map this radiostratigraphy efficiently, we developed new techniques for predicting reflection slope from the phase recorded by coherent radars. When integrated along track, these slope fields predict the radiostratigraphy and simplify semiautomatic reflection tracing. Core-intersecting reflections were dated using synchronized depth-age relationships for six deep ice cores. Additional reflections were dated by matching reflections between transects and by extending reflection-inferred depth-age relationships using the local effective vertical strain rate. The oldest reflections, dating to the Eemian period, are found mostly in the northern part of the ice sheet. Within the onset regions of several fast-flowing outlet glaciers and ice streams, reflections typically do not conform to the bed topography. Disrupted radiostratigraphy is also observed in a region north of the Northeast Greenland Ice Stream that is not presently flowing rapidly. Dated reflections are used to generate a gridded age volume for most of the ice sheet and also to determine the depths of key climate transitions that were not observed directly. This radiostratigraphy provides a new constraint on the dynamics and history of the Greenland Ice Sheet. |
format |
Article in Journal/Newspaper |
author |
Macgregor, JA Fahnestock, MA Catania, GA Paden, JD Prasad Gogineni, S Young, SK Rybarski, SC Mabrey, AN Wagman, BM Morlighem, M |
spellingShingle |
Macgregor, JA Fahnestock, MA Catania, GA Paden, JD Prasad Gogineni, S Young, SK Rybarski, SC Mabrey, AN Wagman, BM Morlighem, M Radiostratigraphy and age structure of the Greenland Ice Sheet |
author_facet |
Macgregor, JA Fahnestock, MA Catania, GA Paden, JD Prasad Gogineni, S Young, SK Rybarski, SC Mabrey, AN Wagman, BM Morlighem, M |
author_sort |
Macgregor, JA |
title |
Radiostratigraphy and age structure of the Greenland Ice Sheet |
title_short |
Radiostratigraphy and age structure of the Greenland Ice Sheet |
title_full |
Radiostratigraphy and age structure of the Greenland Ice Sheet |
title_fullStr |
Radiostratigraphy and age structure of the Greenland Ice Sheet |
title_full_unstemmed |
Radiostratigraphy and age structure of the Greenland Ice Sheet |
title_sort |
radiostratigraphy and age structure of the greenland ice sheet |
publisher |
eScholarship, University of California |
publishDate |
2015 |
url |
http://www.escholarship.org/uc/item/4dj9r5n2 |
geographic |
Antarctic Greenland |
geographic_facet |
Antarctic Greenland |
genre |
Antarc* Antarctic Greenland Ice Sheet |
genre_facet |
Antarc* Antarctic Greenland Ice Sheet |
op_source |
Macgregor, JA; Fahnestock, MA; Catania, GA; Paden, JD; Prasad Gogineni, S; Young, SK; et al.(2015). Radiostratigraphy and age structure of the Greenland Ice Sheet. Journal of Geophysical Research F: Earth Surface. doi:10.1002/2014JF003215. UC Irvine: Retrieved from: http://www.escholarship.org/uc/item/4dj9r5n2 |
op_relation |
qt4dj9r5n2 http://www.escholarship.org/uc/item/4dj9r5n2 |
op_rights |
public |
op_doi |
https://doi.org/10.1002/2014JF003215 |
container_title |
Journal of Geophysical Research: Earth Surface |
container_volume |
120 |
container_issue |
2 |
container_start_page |
212 |
op_container_end_page |
241 |
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1766254262085484544 |