Dating of thaw depths in permafrost terrain by the palaeomagnetic method: experimental acquisition of a freezing remanent magnetization
The acquisition of a freezing remanent magnetization (FRM) has been studied in controlled magnetic and thermal environments by successive freezing and thawing (−18 to +20°C) of samples of natural sediments from a frost polygon near Ny Ålesund, Spitsbergen. Successive freeze-thaw cycles cause a signi...
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1996
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fthighwire:oai:open-archive.highwire.org:gji:125/3/850 2023-05-15T17:48:28+02:00 Dating of thaw depths in permafrost terrain by the palaeomagnetic method: experimental acquisition of a freezing remanent magnetization Løsvlie, Reidar Putkonen, Jaakko 1996-06-01 00:00:00.0 text/html http://gji.oxfordjournals.org/cgi/content/short/125/3/850 https://doi.org/10.1111/j.1365-246X.1996.tb06028.x en eng Oxford University Press http://gji.oxfordjournals.org/cgi/content/short/125/3/850 http://dx.doi.org/10.1111/j.1365-246X.1996.tb06028.x Copyright (C) 1996, Oxford University Press Articles TEXT 1996 fthighwire https://doi.org/10.1111/j.1365-246X.1996.tb06028.x 2012-11-23T22:11:40Z The acquisition of a freezing remanent magnetization (FRM) has been studied in controlled magnetic and thermal environments by successive freezing and thawing (−18 to +20°C) of samples of natural sediments from a frost polygon near Ny Ålesund, Spitsbergen. Successive freeze-thaw cycles cause a significant decrease in the intensity of the initially induced shock remanent magnetization (SRM), associated with directional trends towards the ambient magnetic field direction during the freezing phase. A slow increase in intensity commences after seven to 10 freeze-thaw cycles. The acquisition of a FRM in samples carrying an isothermal remanent magnetization shows a significantly smaller reduction in intensity and only minor directional variations. This result indicates that only a fraction of the magnetic grains in a natural sediment contributes to the natural remanent magnetization. Insignificant changes in lengths and directions of the principal susceptibility ellipsoid axes also indicate that magnetic fabric and remanent magnetization are carried by partly different populations of magnetic grains. The acquisition of a FRM in nature has yet to be explored. If such a process is confirmed, however, it has the potential for obtaining age estimates of ancient thaw depths and for providing insights into material transport processes in frost polygons. Text Ny Ålesund Ny-Ålesund permafrost Spitsbergen HighWire Press (Stanford University) Ny-Ålesund Geophysical Journal International 125 3 850 856 |
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HighWire Press (Stanford University) |
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English |
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Articles |
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Articles Løsvlie, Reidar Putkonen, Jaakko Dating of thaw depths in permafrost terrain by the palaeomagnetic method: experimental acquisition of a freezing remanent magnetization |
topic_facet |
Articles |
description |
The acquisition of a freezing remanent magnetization (FRM) has been studied in controlled magnetic and thermal environments by successive freezing and thawing (−18 to +20°C) of samples of natural sediments from a frost polygon near Ny Ålesund, Spitsbergen. Successive freeze-thaw cycles cause a significant decrease in the intensity of the initially induced shock remanent magnetization (SRM), associated with directional trends towards the ambient magnetic field direction during the freezing phase. A slow increase in intensity commences after seven to 10 freeze-thaw cycles. The acquisition of a FRM in samples carrying an isothermal remanent magnetization shows a significantly smaller reduction in intensity and only minor directional variations. This result indicates that only a fraction of the magnetic grains in a natural sediment contributes to the natural remanent magnetization. Insignificant changes in lengths and directions of the principal susceptibility ellipsoid axes also indicate that magnetic fabric and remanent magnetization are carried by partly different populations of magnetic grains. The acquisition of a FRM in nature has yet to be explored. If such a process is confirmed, however, it has the potential for obtaining age estimates of ancient thaw depths and for providing insights into material transport processes in frost polygons. |
format |
Text |
author |
Løsvlie, Reidar Putkonen, Jaakko |
author_facet |
Løsvlie, Reidar Putkonen, Jaakko |
author_sort |
Løsvlie, Reidar |
title |
Dating of thaw depths in permafrost terrain by the palaeomagnetic method: experimental acquisition of a freezing remanent magnetization |
title_short |
Dating of thaw depths in permafrost terrain by the palaeomagnetic method: experimental acquisition of a freezing remanent magnetization |
title_full |
Dating of thaw depths in permafrost terrain by the palaeomagnetic method: experimental acquisition of a freezing remanent magnetization |
title_fullStr |
Dating of thaw depths in permafrost terrain by the palaeomagnetic method: experimental acquisition of a freezing remanent magnetization |
title_full_unstemmed |
Dating of thaw depths in permafrost terrain by the palaeomagnetic method: experimental acquisition of a freezing remanent magnetization |
title_sort |
dating of thaw depths in permafrost terrain by the palaeomagnetic method: experimental acquisition of a freezing remanent magnetization |
publisher |
Oxford University Press |
publishDate |
1996 |
url |
http://gji.oxfordjournals.org/cgi/content/short/125/3/850 https://doi.org/10.1111/j.1365-246X.1996.tb06028.x |
geographic |
Ny-Ålesund |
geographic_facet |
Ny-Ålesund |
genre |
Ny Ålesund Ny-Ålesund permafrost Spitsbergen |
genre_facet |
Ny Ålesund Ny-Ålesund permafrost Spitsbergen |
op_relation |
http://gji.oxfordjournals.org/cgi/content/short/125/3/850 http://dx.doi.org/10.1111/j.1365-246X.1996.tb06028.x |
op_rights |
Copyright (C) 1996, Oxford University Press |
op_doi |
https://doi.org/10.1111/j.1365-246X.1996.tb06028.x |
container_title |
Geophysical Journal International |
container_volume |
125 |
container_issue |
3 |
container_start_page |
850 |
op_container_end_page |
856 |
_version_ |
1766154539756421120 |