A stratigraphy-based method for reconstructing ice core orientation
Ever since the first deep ice cores were drilled, it has been a challenge to determine their original, in-situ orientation. In general, the orientation of an ice core is lost as the drill is free to rotate during transport to the surface. For shallow ice cores, it is usually possible to match the ad...
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Cambridge University Press
2021-09-01
|
| Series: | Annals of Glaciology |
| Subjects: | |
| Online Access: | https://www.cambridge.org/core/product/identifier/S0260305520000762/type/journal_article |
| _version_ | 1811157278317871104 |
|---|---|
| author | Julien Westhoff Nicolas Stoll Steven Franke Ilka Weikusat Paul Bons Johanna Kerch Daniela Jansen Sepp Kipfstuhl Dorthe Dahl-Jensen |
| author_facet | Julien Westhoff Nicolas Stoll Steven Franke Ilka Weikusat Paul Bons Johanna Kerch Daniela Jansen Sepp Kipfstuhl Dorthe Dahl-Jensen |
| author_sort | Julien Westhoff |
| collection | DOAJ |
| description | Ever since the first deep ice cores were drilled, it has been a challenge to determine their original, in-situ orientation. In general, the orientation of an ice core is lost as the drill is free to rotate during transport to the surface. For shallow ice cores, it is usually possible to match the adjacent core breaks, which preserves the orientation of the ice column. However, this method fails for deep ice cores, such as the EastGRIP ice core in Northeast Greenland. We provide a method to reconstruct ice core orientation using visual stratigraphy and borehole geometry. As the EastGRIP ice core is drilled through the Northeast Greenland Ice Stream, we use information about the directional structures to perform a full geographical re-orientation. We compared the core orientation with logging data from core break matching and the pattern of the stereographic projections of the crystals’ c-axis orientations. Both comparisons agree very well with the proposed orientation method. The method works well for 441 out of 451 samples from a depth of 1375–2120 m in the EastGRIP ice core. It can also be applied to other ice cores, providing a better foundation for interpreting physical properties and understanding the flow of ice. |
| first_indexed | 2024-04-10T05:03:26Z |
| format | Article |
| id | doaj.art-395687d7ac1444a387037b3bc574cedc |
| institution | Directory Open Access Journal |
| issn | 0260-3055 1727-5644 |
| language | English |
| last_indexed | 2024-04-10T05:03:26Z |
| publishDate | 2021-09-01 |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Annals of Glaciology |
| spelling | doaj.art-395687d7ac1444a387037b3bc574cedc2023-03-09T12:27:43ZengCambridge University PressAnnals of Glaciology0260-30551727-56442021-09-016219120210.1017/aog.2020.76A stratigraphy-based method for reconstructing ice core orientationJulien Westhoff0https://orcid.org/0000-0001-7818-1786Nicolas Stoll1https://orcid.org/0000-0002-3219-8395Steven Franke2https://orcid.org/0000-0001-8462-4379Ilka Weikusat3https://orcid.org/0000-0002-3023-6036Paul Bons4https://orcid.org/0000-0002-6469-3526Johanna Kerch5https://orcid.org/0000-0002-7200-6837Daniela Jansen6https://orcid.org/0000-0002-4412-5820Sepp Kipfstuhl7https://orcid.org/0000-0003-1495-5273Dorthe Dahl-Jensen8https://orcid.org/0000-0002-1474-1948Physics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, DenmarkAlfred Wegener, Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyAlfred Wegener, Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyAlfred Wegener, Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany Department of Geosciences, Eberhard Karls University Tübingen, Tübingen, GermanyDepartment of Geosciences, Eberhard Karls University Tübingen, Tübingen, GermanyAlfred Wegener, Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyAlfred Wegener, Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyPhysics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark Alfred Wegener, Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyPhysics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark Centre for Earth Observation Science, University of Manitoba, Winnipeg, CanadaEver since the first deep ice cores were drilled, it has been a challenge to determine their original, in-situ orientation. In general, the orientation of an ice core is lost as the drill is free to rotate during transport to the surface. For shallow ice cores, it is usually possible to match the adjacent core breaks, which preserves the orientation of the ice column. However, this method fails for deep ice cores, such as the EastGRIP ice core in Northeast Greenland. We provide a method to reconstruct ice core orientation using visual stratigraphy and borehole geometry. As the EastGRIP ice core is drilled through the Northeast Greenland Ice Stream, we use information about the directional structures to perform a full geographical re-orientation. We compared the core orientation with logging data from core break matching and the pattern of the stereographic projections of the crystals’ c-axis orientations. Both comparisons agree very well with the proposed orientation method. The method works well for 441 out of 451 samples from a depth of 1375–2120 m in the EastGRIP ice core. It can also be applied to other ice cores, providing a better foundation for interpreting physical properties and understanding the flow of ice.https://www.cambridge.org/core/product/identifier/S0260305520000762/type/journal_articleGlaciological instruments and methodsice corestructural glaciology |
| spellingShingle | Julien Westhoff Nicolas Stoll Steven Franke Ilka Weikusat Paul Bons Johanna Kerch Daniela Jansen Sepp Kipfstuhl Dorthe Dahl-Jensen A stratigraphy-based method for reconstructing ice core orientation Annals of Glaciology Glaciological instruments and methods ice core structural glaciology |
| title | A stratigraphy-based method for reconstructing ice core orientation |
| title_full | A stratigraphy-based method for reconstructing ice core orientation |
| title_fullStr | A stratigraphy-based method for reconstructing ice core orientation |
| title_full_unstemmed | A stratigraphy-based method for reconstructing ice core orientation |
| title_short | A stratigraphy-based method for reconstructing ice core orientation |
| title_sort | stratigraphy based method for reconstructing ice core orientation |
| topic | Glaciological instruments and methods ice core structural glaciology |
| url | https://www.cambridge.org/core/product/identifier/S0260305520000762/type/journal_article |
| work_keys_str_mv | AT julienwesthoff astratigraphybasedmethodforreconstructingicecoreorientation AT nicolasstoll astratigraphybasedmethodforreconstructingicecoreorientation AT stevenfranke astratigraphybasedmethodforreconstructingicecoreorientation AT ilkaweikusat astratigraphybasedmethodforreconstructingicecoreorientation AT paulbons astratigraphybasedmethodforreconstructingicecoreorientation AT johannakerch astratigraphybasedmethodforreconstructingicecoreorientation AT danielajansen astratigraphybasedmethodforreconstructingicecoreorientation AT seppkipfstuhl astratigraphybasedmethodforreconstructingicecoreorientation AT dorthedahljensen astratigraphybasedmethodforreconstructingicecoreorientation AT julienwesthoff stratigraphybasedmethodforreconstructingicecoreorientation AT nicolasstoll stratigraphybasedmethodforreconstructingicecoreorientation AT stevenfranke stratigraphybasedmethodforreconstructingicecoreorientation AT ilkaweikusat stratigraphybasedmethodforreconstructingicecoreorientation AT paulbons stratigraphybasedmethodforreconstructingicecoreorientation AT johannakerch stratigraphybasedmethodforreconstructingicecoreorientation AT danielajansen stratigraphybasedmethodforreconstructingicecoreorientation AT seppkipfstuhl stratigraphybasedmethodforreconstructingicecoreorientation AT dorthedahljensen stratigraphybasedmethodforreconstructingicecoreorientation |