The Extraterrestrial Dust Flux: Size Distribution and Mass Contribution Estimates Inferred From the Transantarctic Mountains (TAM) Micrometeorite Collection
This study explores the long‐duration (0.8–2.3 Ma), time‐averaged micrometeorite flux (mass and size distribution) reaching Earth, as recorded by the Transantarctic Mountains (TAM) micrometeorite collection. We investigate a single sediment trap (TAM65), performing an exhaustive recovery and charact...
Published in: | Journal of Geophysical Research: Planets |
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Language: | English |
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Online Access: | http://hdl.handle.net/11568/1035482 https://doi.org/10.1029/2019JE006241 |
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ftunivpisairis:oai:arpi.unipi.it:11568/1035482 2024-02-27T08:33:39+00:00 The Extraterrestrial Dust Flux: Size Distribution and Mass Contribution Estimates Inferred From the Transantarctic Mountains (TAM) Micrometeorite Collection Suttle, M. D. Folco, L. Suttle, M. D. Folco, L. 2020 ELETTRONICO http://hdl.handle.net/11568/1035482 https://doi.org/10.1029/2019JE006241 eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000535272500011 volume:125 issue:2 journal:JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS http://hdl.handle.net/11568/1035482 doi:10.1029/2019JE006241 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85080030412 info:eu-repo/semantics/openAccess DEEP-SEA SPHERULES COSMIC SPHERULES INTERPLANETARY DUST INTERNAL STRUCTURE FRONTIER MOUNTAIN ACCRETION RATE ANTARCTIC ICE VICTORIA LAND EARTH INFLUX info:eu-repo/semantics/article 2020 ftunivpisairis https://doi.org/10.1029/2019JE006241 2024-01-31T17:55:11Z This study explores the long‐duration (0.8–2.3 Ma), time‐averaged micrometeorite flux (mass and size distribution) reaching Earth, as recorded by the Transantarctic Mountains (TAM) micrometeorite collection. We investigate a single sediment trap (TAM65), performing an exhaustive recovery and characterization effort and identifying 1,643 micrometeorites (between 100 and 2,000 μm). Approximately 7% of particles are unmelted or scoriaceous, of which 75% are fine‐grained. Among cosmic spherules, 95.6% are silicate‐dominated S‐types, and further subdivided into porphyritic (16.9%), barred olivine (19.9%), cryptocrystalline (51.6%), and vitreous (7.5%). Our (rank)‐size distribution is fit against a power law with a slope of −3.9 (R2 = 0.98) over the size range 200–700 μm. However, the distribution is also bimodal, with peaks centered at ~145 and ~250 μm. Remarkably similar peak positions are observed in the Larkman Nunatak data. These observations suggest that the micrometeorite flux is composed of multiple dust sources with distinct size distributions. In terms of mass, the TAM65 trap contains 1.77 g of extraterrestrial dust in 15 kg of sediment (<5 mm). Upscaling to a global annual estimate gives 1,555 (±753) t/year—consistent with previous micrometeorite abundance estimates and almost identical to the South Pole Water Well estimate (~1,600 t/year), potentially indicating minimal variation in the background cosmic dust flux over the Quaternary. The greatest uncertainty in our mass flux calculation is the accumulation window. A minimum age (0.8 Ma) is robustly inferred from the presence of Australasian microtektites, while the upper age (~2.3 Ma) is loosely constrained based on 10Be exposure dating of glacial surfaces at Roberts Butte (6 km from our sample site). Article in Journal/Newspaper Antarc* Antarctic South pole South pole Victoria Land ARPI - Archivio della Ricerca dell'Università di Pisa Antarctic Frontier Mountain ENVELOPE(160.333,160.333,-72.983,-72.983) Larkman Nunatak ENVELOPE(179.383,179.383,-85.767,-85.767) Roberts Butte ENVELOPE(160.133,160.133,-72.650,-72.650) South Pole Transantarctic Mountains Victoria Land Journal of Geophysical Research: Planets 125 2 |
institution |
Open Polar |
collection |
ARPI - Archivio della Ricerca dell'Università di Pisa |
op_collection_id |
ftunivpisairis |
language |
English |
topic |
DEEP-SEA SPHERULES COSMIC SPHERULES INTERPLANETARY DUST INTERNAL STRUCTURE FRONTIER MOUNTAIN ACCRETION RATE ANTARCTIC ICE VICTORIA LAND EARTH INFLUX |
spellingShingle |
DEEP-SEA SPHERULES COSMIC SPHERULES INTERPLANETARY DUST INTERNAL STRUCTURE FRONTIER MOUNTAIN ACCRETION RATE ANTARCTIC ICE VICTORIA LAND EARTH INFLUX Suttle, M. D. Folco, L. The Extraterrestrial Dust Flux: Size Distribution and Mass Contribution Estimates Inferred From the Transantarctic Mountains (TAM) Micrometeorite Collection |
topic_facet |
DEEP-SEA SPHERULES COSMIC SPHERULES INTERPLANETARY DUST INTERNAL STRUCTURE FRONTIER MOUNTAIN ACCRETION RATE ANTARCTIC ICE VICTORIA LAND EARTH INFLUX |
description |
This study explores the long‐duration (0.8–2.3 Ma), time‐averaged micrometeorite flux (mass and size distribution) reaching Earth, as recorded by the Transantarctic Mountains (TAM) micrometeorite collection. We investigate a single sediment trap (TAM65), performing an exhaustive recovery and characterization effort and identifying 1,643 micrometeorites (between 100 and 2,000 μm). Approximately 7% of particles are unmelted or scoriaceous, of which 75% are fine‐grained. Among cosmic spherules, 95.6% are silicate‐dominated S‐types, and further subdivided into porphyritic (16.9%), barred olivine (19.9%), cryptocrystalline (51.6%), and vitreous (7.5%). Our (rank)‐size distribution is fit against a power law with a slope of −3.9 (R2 = 0.98) over the size range 200–700 μm. However, the distribution is also bimodal, with peaks centered at ~145 and ~250 μm. Remarkably similar peak positions are observed in the Larkman Nunatak data. These observations suggest that the micrometeorite flux is composed of multiple dust sources with distinct size distributions. In terms of mass, the TAM65 trap contains 1.77 g of extraterrestrial dust in 15 kg of sediment (<5 mm). Upscaling to a global annual estimate gives 1,555 (±753) t/year—consistent with previous micrometeorite abundance estimates and almost identical to the South Pole Water Well estimate (~1,600 t/year), potentially indicating minimal variation in the background cosmic dust flux over the Quaternary. The greatest uncertainty in our mass flux calculation is the accumulation window. A minimum age (0.8 Ma) is robustly inferred from the presence of Australasian microtektites, while the upper age (~2.3 Ma) is loosely constrained based on 10Be exposure dating of glacial surfaces at Roberts Butte (6 km from our sample site). |
author2 |
Suttle, M. D. Folco, L. |
format |
Article in Journal/Newspaper |
author |
Suttle, M. D. Folco, L. |
author_facet |
Suttle, M. D. Folco, L. |
author_sort |
Suttle, M. D. |
title |
The Extraterrestrial Dust Flux: Size Distribution and Mass Contribution Estimates Inferred From the Transantarctic Mountains (TAM) Micrometeorite Collection |
title_short |
The Extraterrestrial Dust Flux: Size Distribution and Mass Contribution Estimates Inferred From the Transantarctic Mountains (TAM) Micrometeorite Collection |
title_full |
The Extraterrestrial Dust Flux: Size Distribution and Mass Contribution Estimates Inferred From the Transantarctic Mountains (TAM) Micrometeorite Collection |
title_fullStr |
The Extraterrestrial Dust Flux: Size Distribution and Mass Contribution Estimates Inferred From the Transantarctic Mountains (TAM) Micrometeorite Collection |
title_full_unstemmed |
The Extraterrestrial Dust Flux: Size Distribution and Mass Contribution Estimates Inferred From the Transantarctic Mountains (TAM) Micrometeorite Collection |
title_sort |
extraterrestrial dust flux: size distribution and mass contribution estimates inferred from the transantarctic mountains (tam) micrometeorite collection |
publishDate |
2020 |
url |
http://hdl.handle.net/11568/1035482 https://doi.org/10.1029/2019JE006241 |
long_lat |
ENVELOPE(160.333,160.333,-72.983,-72.983) ENVELOPE(179.383,179.383,-85.767,-85.767) ENVELOPE(160.133,160.133,-72.650,-72.650) |
geographic |
Antarctic Frontier Mountain Larkman Nunatak Roberts Butte South Pole Transantarctic Mountains Victoria Land |
geographic_facet |
Antarctic Frontier Mountain Larkman Nunatak Roberts Butte South Pole Transantarctic Mountains Victoria Land |
genre |
Antarc* Antarctic South pole South pole Victoria Land |
genre_facet |
Antarc* Antarctic South pole South pole Victoria Land |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000535272500011 volume:125 issue:2 journal:JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS http://hdl.handle.net/11568/1035482 doi:10.1029/2019JE006241 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85080030412 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1029/2019JE006241 |
container_title |
Journal of Geophysical Research: Planets |
container_volume |
125 |
container_issue |
2 |
_version_ |
1792046805525987328 |