Meteoric smoke fallout revealed by superparamagnetism in Greenland ice
Meteoric material reaching Earth contains an appreciable percentage of iron, much of which can be oxidized into nanometric-size particles produced by ablation and subsequent condensation in the atmosphere. New measurements of isothermal remanent magnetization (IRM) show that magnetic particles of ex...
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ftcolumbiauniv:oai:academiccommons.columbia.edu:10.7916/D8HX1BDW 2023-05-15T16:26:13+02:00 Meteoric smoke fallout revealed by superparamagnetism in Greenland ice Lanci, L. Kent, Dennis V. 2006 https://doi.org/10.7916/D8HX1BDW English eng https://doi.org/10.7916/D8HX1BDW Geology Meteorology Articles 2006 ftcolumbiauniv https://doi.org/10.7916/D8HX1BDW 2019-04-04T08:12:09Z Meteoric material reaching Earth contains an appreciable percentage of iron, much of which can be oxidized into nanometric-size particles produced by ablation and subsequent condensation in the atmosphere. New measurements of isothermal remanent magnetization (IRM) show that magnetic particles of extraterrestrial origin can be distinguished from terrigenous particles based on their smaller superparamagnetic (SP) size as inferred from magnetic relaxation and by the poor correlation of the SP fraction with dust contents. The magnetic relaxation data suggest that extraterrestrial magnetic particles are in the size range of about 7 – 17 nm, which is compatible with the expected size of condensed particles. The concentration of extraterrestrial material in Greenland ice was estimated from the magnetic relaxation data. Assuming an iron content typical of average chondritic composition, the results correspond to a particles concentration of 0.78 ± 0.22 ppb for Greenland, good agreement with results based on iridium concentrations in NGRIP ice samples. Article in Journal/Newspaper Greenland NGRIP Columbia University: Academic Commons Greenland |
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Open Polar |
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Columbia University: Academic Commons |
op_collection_id |
ftcolumbiauniv |
language |
English |
topic |
Geology Meteorology |
spellingShingle |
Geology Meteorology Lanci, L. Kent, Dennis V. Meteoric smoke fallout revealed by superparamagnetism in Greenland ice |
topic_facet |
Geology Meteorology |
description |
Meteoric material reaching Earth contains an appreciable percentage of iron, much of which can be oxidized into nanometric-size particles produced by ablation and subsequent condensation in the atmosphere. New measurements of isothermal remanent magnetization (IRM) show that magnetic particles of extraterrestrial origin can be distinguished from terrigenous particles based on their smaller superparamagnetic (SP) size as inferred from magnetic relaxation and by the poor correlation of the SP fraction with dust contents. The magnetic relaxation data suggest that extraterrestrial magnetic particles are in the size range of about 7 – 17 nm, which is compatible with the expected size of condensed particles. The concentration of extraterrestrial material in Greenland ice was estimated from the magnetic relaxation data. Assuming an iron content typical of average chondritic composition, the results correspond to a particles concentration of 0.78 ± 0.22 ppb for Greenland, good agreement with results based on iridium concentrations in NGRIP ice samples. |
format |
Article in Journal/Newspaper |
author |
Lanci, L. Kent, Dennis V. |
author_facet |
Lanci, L. Kent, Dennis V. |
author_sort |
Lanci, L. |
title |
Meteoric smoke fallout revealed by superparamagnetism in Greenland ice |
title_short |
Meteoric smoke fallout revealed by superparamagnetism in Greenland ice |
title_full |
Meteoric smoke fallout revealed by superparamagnetism in Greenland ice |
title_fullStr |
Meteoric smoke fallout revealed by superparamagnetism in Greenland ice |
title_full_unstemmed |
Meteoric smoke fallout revealed by superparamagnetism in Greenland ice |
title_sort |
meteoric smoke fallout revealed by superparamagnetism in greenland ice |
publishDate |
2006 |
url |
https://doi.org/10.7916/D8HX1BDW |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland NGRIP |
genre_facet |
Greenland NGRIP |
op_relation |
https://doi.org/10.7916/D8HX1BDW |
op_doi |
https://doi.org/10.7916/D8HX1BDW |
_version_ |
1766015105982529536 |