High-Resolution Study of Layering Within the Percolation and Soaked Facies of the Greenland Ice Sheet
Within the percolation and soaked facies of the Greenland ice sheet, the relationship between radar-derived internal reflection horizons and the layered structure of the firn column is unclear. We conducted two small-scale ground-penetrating radar (GPR) surveys in conjunction with 10 m firn cores th...
Published in: | Annals of Glaciology |
---|---|
Main Authors: | , , , , |
Format: | Text |
Language: | unknown |
Published: |
ScholarWorks
2011
|
Subjects: | |
Online Access: | https://scholarworks.boisestate.edu/cgiss_facpubs/157 https://doi.org/10.3189/172756411799096286 |
id |
ftboisestateu:oai:scholarworks.boisestate.edu:cgiss_facpubs-1156 |
---|---|
record_format |
openpolar |
spelling |
ftboisestateu:oai:scholarworks.boisestate.edu:cgiss_facpubs-1156 2023-10-29T02:36:42+01:00 High-Resolution Study of Layering Within the Percolation and Soaked Facies of the Greenland Ice Sheet Brown, Joel Harper, Joel Pfeffer, W. Tad Humphrey, Neil Bradford, John 2011-12-01T08:00:00Z https://scholarworks.boisestate.edu/cgiss_facpubs/157 https://doi.org/10.3189/172756411799096286 unknown ScholarWorks https://scholarworks.boisestate.edu/cgiss_facpubs/157 http://dx.doi.org/10.3189/172756411799096286 CGISS Publications and Presentations Geosciences Earth Sciences Geophysics and Seismology text 2011 ftboisestateu https://doi.org/10.3189/172756411799096286 2023-09-29T15:08:46Z Within the percolation and soaked facies of the Greenland ice sheet, the relationship between radar-derived internal reflection horizons and the layered structure of the firn column is unclear. We conducted two small-scale ground-penetrating radar (GPR) surveys in conjunction with 10 m firn cores that we collected within the percolation and soaked facies of the Greenland ice sheet. The two surveys were separated by a distance of ∼50 km and ∼340 m of elevation leading to ∼40 days of difference in the duration of average annual melt. At the higher site (∼1997 m a.s.l.), which receives less melt, we found that internal reflection horizons identified in GPR data were largely laterally continuous over the grid; however, stratigraphic layers identified in cores could not be traced between cores over any distance from 1.5 to 14.0 m. Thus, we found no correlation between firn core stratigraphy observed directly and radar-derived internal reflection horizons. At the lower site (∼1660 m a.s.l.), which receives more melt, we found massive ice layers >0.5 m thick and stratigraphic boundaries that span >15 m horizontally. Some ice layers and stratigraphic boundaries correlate well with internal reflection horizons that are laterally continuous over the area of the radar grid. Internal reflection horizons identified at ∼1997 m a.s.l. are likely annual isochrones, but the reflection horizons identified at ∼1660 m a.s.l. are likely multi-annual features. We find that mapping accumulation rates over long distances by tying core stratigraphy to radar horizons may lead to ambiguous results because: (1) there is no stratigraphic correlation between firn cores at the 1997 m location; and (2) the reflection horizons at the 1660 m location are multi-annual features. Text Greenland Ice Sheet Boise State University: Scholar Works Annals of Glaciology 52 59 35 42 |
institution |
Open Polar |
collection |
Boise State University: Scholar Works |
op_collection_id |
ftboisestateu |
language |
unknown |
topic |
Geosciences Earth Sciences Geophysics and Seismology |
spellingShingle |
Geosciences Earth Sciences Geophysics and Seismology Brown, Joel Harper, Joel Pfeffer, W. Tad Humphrey, Neil Bradford, John High-Resolution Study of Layering Within the Percolation and Soaked Facies of the Greenland Ice Sheet |
topic_facet |
Geosciences Earth Sciences Geophysics and Seismology |
description |
Within the percolation and soaked facies of the Greenland ice sheet, the relationship between radar-derived internal reflection horizons and the layered structure of the firn column is unclear. We conducted two small-scale ground-penetrating radar (GPR) surveys in conjunction with 10 m firn cores that we collected within the percolation and soaked facies of the Greenland ice sheet. The two surveys were separated by a distance of ∼50 km and ∼340 m of elevation leading to ∼40 days of difference in the duration of average annual melt. At the higher site (∼1997 m a.s.l.), which receives less melt, we found that internal reflection horizons identified in GPR data were largely laterally continuous over the grid; however, stratigraphic layers identified in cores could not be traced between cores over any distance from 1.5 to 14.0 m. Thus, we found no correlation between firn core stratigraphy observed directly and radar-derived internal reflection horizons. At the lower site (∼1660 m a.s.l.), which receives more melt, we found massive ice layers >0.5 m thick and stratigraphic boundaries that span >15 m horizontally. Some ice layers and stratigraphic boundaries correlate well with internal reflection horizons that are laterally continuous over the area of the radar grid. Internal reflection horizons identified at ∼1997 m a.s.l. are likely annual isochrones, but the reflection horizons identified at ∼1660 m a.s.l. are likely multi-annual features. We find that mapping accumulation rates over long distances by tying core stratigraphy to radar horizons may lead to ambiguous results because: (1) there is no stratigraphic correlation between firn cores at the 1997 m location; and (2) the reflection horizons at the 1660 m location are multi-annual features. |
format |
Text |
author |
Brown, Joel Harper, Joel Pfeffer, W. Tad Humphrey, Neil Bradford, John |
author_facet |
Brown, Joel Harper, Joel Pfeffer, W. Tad Humphrey, Neil Bradford, John |
author_sort |
Brown, Joel |
title |
High-Resolution Study of Layering Within the Percolation and Soaked Facies of the Greenland Ice Sheet |
title_short |
High-Resolution Study of Layering Within the Percolation and Soaked Facies of the Greenland Ice Sheet |
title_full |
High-Resolution Study of Layering Within the Percolation and Soaked Facies of the Greenland Ice Sheet |
title_fullStr |
High-Resolution Study of Layering Within the Percolation and Soaked Facies of the Greenland Ice Sheet |
title_full_unstemmed |
High-Resolution Study of Layering Within the Percolation and Soaked Facies of the Greenland Ice Sheet |
title_sort |
high-resolution study of layering within the percolation and soaked facies of the greenland ice sheet |
publisher |
ScholarWorks |
publishDate |
2011 |
url |
https://scholarworks.boisestate.edu/cgiss_facpubs/157 https://doi.org/10.3189/172756411799096286 |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_source |
CGISS Publications and Presentations |
op_relation |
https://scholarworks.boisestate.edu/cgiss_facpubs/157 http://dx.doi.org/10.3189/172756411799096286 |
op_doi |
https://doi.org/10.3189/172756411799096286 |
container_title |
Annals of Glaciology |
container_volume |
52 |
container_issue |
59 |
container_start_page |
35 |
op_container_end_page |
42 |
_version_ |
1781060778160291840 |