Meteoritic ablation debris from the Transantarctic Mountains: Evidence for a Tunguska-like impact over Antarctica ca. 480 ka ago
Aggregates of microscopic spherules broadly similar in texture and composition to cosmic spherules or meteorite ablation spheres were discovered within the ∼1 Ma-old Transantarctic Mountain micrometeorite traps at Miller Butte, Victoria Land, Antarctica. Mineralogical and geochemical data obtained b...
Published in: | Earth and Planetary Science Letters |
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Online Access: | http://hdl.handle.net/11568/194828 https://doi.org/10.1016/j.epsl.2010.02.028 |
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ftunivpisairis:oai:arpi.unipi.it:11568/194828 2024-02-27T08:35:03+00:00 Meteoritic ablation debris from the Transantarctic Mountains: Evidence for a Tunguska-like impact over Antarctica ca. 480 ka ago Van Ginneken M. FOLCO, LUIGI PERCHIAZZI, NATALE Rochette P. Bland P. A. Van Ginneken, M. Folco, Luigi Perchiazzi, Natale Rochette, P. Bland, P. A. 2010 STAMPA http://hdl.handle.net/11568/194828 https://doi.org/10.1016/j.epsl.2010.02.028 eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000277217100010 volume:293 firstpage:104 lastpage:113 numberofpages:10 journal:EARTH AND PLANETARY SCIENCE LETTERS http://hdl.handle.net/11568/194828 doi:10.1016/j.epsl.2010.02.028 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-77950341377 info:eu-repo/semantics/article 2010 ftunivpisairis https://doi.org/10.1016/j.epsl.2010.02.028 2024-01-31T17:44:15Z Aggregates of microscopic spherules broadly similar in texture and composition to cosmic spherules or meteorite ablation spheres were discovered within the ∼1 Ma-old Transantarctic Mountain micrometeorite traps at Miller Butte, Victoria Land, Antarctica. Mineralogical and geochemical data obtained by means of field emission-scanning electron microscopy, electron microprobe analyses, synchrotron X-ray diffraction, and magnetization measurements show that they consist of a porous aggregate of quench-textured spherules, with individual spherules ranging from less than 1 to 65 μm in diameter. Spherule types include porphyritic olivine plus magnesioferrite spherules, dendritic magnesioferrite spherules, barred and feathered olivine spherules, and cryptocrystalline spherules. In contrast to the textural variations, the bulk composition of the individual spherules is fairly homogeneous and broadly chondritic. Likewise olivine has a nearly homogeneous composition Fa16.3±2.7. Olivine and magnesioferrite are characterized by high NiO contents (2.72±1.6 and 4.68±0.68 wt.%, respectively), as typically observed in ablation debris and meteorite fusion crusts. The bulk composition of the aggregates is similar to the fusion crust of ordinary and carbonaceous chondrites. We interpret the spherulitic aggregates as meteorite ablation debris formed during the atmospheric entry of a large meteorite of ordinary or carbonaceous chondritic composition. Comparison with the available literature data shows that the ablation debris found at Miller Butte is most likely paired with the extraterrestrial dust found in a ∼480 ka-old ice layer in the EPICA-Dome C and Dome Fuji ice cores (East Antarctic ice sheet), thereby documenting a continental-scale distribution of ablation debris associated with a major meteoritic impact event which occurred ∼480 ka ago. Based on estimates of the projectile mass (N108 kg) and numerical simulation of small-scale impacts from literature, we propose that the continentalscale distribution of the ablation debris ... Article in Journal/Newspaper Antarc* Antarctic Antarctica EPICA Ice Sheet Victoria Land ARPI - Archivio della Ricerca dell'Università di Pisa Antarctic Victoria Land East Antarctic Ice Sheet Transantarctic Mountains Dome Fuji ENVELOPE(39.700,39.700,-77.317,-77.317) Tunguska ENVELOPE(144.784,144.784,59.388,59.388) Miller Butte ENVELOPE(160.250,160.250,-72.700,-72.700) Earth and Planetary Science Letters 293 1-2 104 113 |
institution |
Open Polar |
collection |
ARPI - Archivio della Ricerca dell'Università di Pisa |
op_collection_id |
ftunivpisairis |
language |
English |
description |
Aggregates of microscopic spherules broadly similar in texture and composition to cosmic spherules or meteorite ablation spheres were discovered within the ∼1 Ma-old Transantarctic Mountain micrometeorite traps at Miller Butte, Victoria Land, Antarctica. Mineralogical and geochemical data obtained by means of field emission-scanning electron microscopy, electron microprobe analyses, synchrotron X-ray diffraction, and magnetization measurements show that they consist of a porous aggregate of quench-textured spherules, with individual spherules ranging from less than 1 to 65 μm in diameter. Spherule types include porphyritic olivine plus magnesioferrite spherules, dendritic magnesioferrite spherules, barred and feathered olivine spherules, and cryptocrystalline spherules. In contrast to the textural variations, the bulk composition of the individual spherules is fairly homogeneous and broadly chondritic. Likewise olivine has a nearly homogeneous composition Fa16.3±2.7. Olivine and magnesioferrite are characterized by high NiO contents (2.72±1.6 and 4.68±0.68 wt.%, respectively), as typically observed in ablation debris and meteorite fusion crusts. The bulk composition of the aggregates is similar to the fusion crust of ordinary and carbonaceous chondrites. We interpret the spherulitic aggregates as meteorite ablation debris formed during the atmospheric entry of a large meteorite of ordinary or carbonaceous chondritic composition. Comparison with the available literature data shows that the ablation debris found at Miller Butte is most likely paired with the extraterrestrial dust found in a ∼480 ka-old ice layer in the EPICA-Dome C and Dome Fuji ice cores (East Antarctic ice sheet), thereby documenting a continental-scale distribution of ablation debris associated with a major meteoritic impact event which occurred ∼480 ka ago. Based on estimates of the projectile mass (N108 kg) and numerical simulation of small-scale impacts from literature, we propose that the continentalscale distribution of the ablation debris ... |
author2 |
Van Ginneken, M. Folco, Luigi Perchiazzi, Natale Rochette, P. Bland, P. A. |
format |
Article in Journal/Newspaper |
author |
Van Ginneken M. FOLCO, LUIGI PERCHIAZZI, NATALE Rochette P. Bland P. A. |
spellingShingle |
Van Ginneken M. FOLCO, LUIGI PERCHIAZZI, NATALE Rochette P. Bland P. A. Meteoritic ablation debris from the Transantarctic Mountains: Evidence for a Tunguska-like impact over Antarctica ca. 480 ka ago |
author_facet |
Van Ginneken M. FOLCO, LUIGI PERCHIAZZI, NATALE Rochette P. Bland P. A. |
author_sort |
Van Ginneken M. |
title |
Meteoritic ablation debris from the Transantarctic Mountains: Evidence for a Tunguska-like impact over Antarctica ca. 480 ka ago |
title_short |
Meteoritic ablation debris from the Transantarctic Mountains: Evidence for a Tunguska-like impact over Antarctica ca. 480 ka ago |
title_full |
Meteoritic ablation debris from the Transantarctic Mountains: Evidence for a Tunguska-like impact over Antarctica ca. 480 ka ago |
title_fullStr |
Meteoritic ablation debris from the Transantarctic Mountains: Evidence for a Tunguska-like impact over Antarctica ca. 480 ka ago |
title_full_unstemmed |
Meteoritic ablation debris from the Transantarctic Mountains: Evidence for a Tunguska-like impact over Antarctica ca. 480 ka ago |
title_sort |
meteoritic ablation debris from the transantarctic mountains: evidence for a tunguska-like impact over antarctica ca. 480 ka ago |
publishDate |
2010 |
url |
http://hdl.handle.net/11568/194828 https://doi.org/10.1016/j.epsl.2010.02.028 |
long_lat |
ENVELOPE(39.700,39.700,-77.317,-77.317) ENVELOPE(144.784,144.784,59.388,59.388) ENVELOPE(160.250,160.250,-72.700,-72.700) |
geographic |
Antarctic Victoria Land East Antarctic Ice Sheet Transantarctic Mountains Dome Fuji Tunguska Miller Butte |
geographic_facet |
Antarctic Victoria Land East Antarctic Ice Sheet Transantarctic Mountains Dome Fuji Tunguska Miller Butte |
genre |
Antarc* Antarctic Antarctica EPICA Ice Sheet Victoria Land |
genre_facet |
Antarc* Antarctic Antarctica EPICA Ice Sheet Victoria Land |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000277217100010 volume:293 firstpage:104 lastpage:113 numberofpages:10 journal:EARTH AND PLANETARY SCIENCE LETTERS http://hdl.handle.net/11568/194828 doi:10.1016/j.epsl.2010.02.028 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-77950341377 |
op_doi |
https://doi.org/10.1016/j.epsl.2010.02.028 |
container_title |
Earth and Planetary Science Letters |
container_volume |
293 |
container_issue |
1-2 |
container_start_page |
104 |
op_container_end_page |
113 |
_version_ |
1792041480889565184 |