Granulite-facies beryllium pegmatites in the Napier Complex in Khmara and Amundsen Bays, western Enderby Land, East Antarctica
Four granulite-facies beryllium pegmatites of Late Archean age intrude ultrahigh-temperature Napier Complex metapelites in Khmara Bay at "Christmas Point" and "Zircon Point" and in Amundsen Bay on Mt. Pardoe. The pegmatites evolved in three major stages. During the first stage, m...
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ftnipr:oai:nipr.repo.nii.ac.jp:00003064 2023-05-15T13:22:48+02:00 Granulite-facies beryllium pegmatites in the Napier Complex in Khmara and Amundsen Bays, western Enderby Land, East Antarctica Edward S. Grew Martin G. Yates Jacques Barbier Charles K. Shearer John W. Sheraton Kazuyuki Shiraishi Yoichi Motoyoshi 2000-10 https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=3064 http://id.nii.ac.jp/1291/00003064/ https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=3064&item_no=1&attribute_id=18&file_no=1 en eng Department of Geological Sciences, University of Maine/Department of Geological Sciences, University of Maine/Department of Chemistry, McMaster University/Institute of Meteoritics, University of New Mexico/Department of Geology, Australian National University/National Institute of Polar Research/National Institute of Polar Research National Institute of Polar Research https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=3064 http://id.nii.ac.jp/1291/00003064/ AA1130866X Polar geoscience, 13, 1-40(2000-10) https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=3064&item_no=1&attribute_id=18&file_no=1 pegmatite beryllium Antarctica Archean/Archaean Departmental Bulletin Paper P(論文) 2000 ftnipr 2022-11-26T19:42:23Z Four granulite-facies beryllium pegmatites of Late Archean age intrude ultrahigh-temperature Napier Complex metapelites in Khmara Bay at "Christmas Point" and "Zircon Point" and in Amundsen Bay on Mt. Pardoe. The pegmatites evolved in three major stages. During the first stage, melt from anatexis of sapphirine-bearing metapelites soon after temperatures peaked during ultrahigh-temperature metamorphism crystallized as pegmatites in inter-boudin spaces during the waning stages of associated deformation. The primary carrier of beryllium in the pegmatites at the time of their intrusion was a sapphirine-group mineral. The second stage is high-temperature metamorphism at moderate pressure, which resulted in reaction of sapphirine with quartz to form corona assemblages of sillimanite+orthopyroxene (or garnet) in the host rocks and sillimanite+garnet+ surinamite in the beryllium pegmatites. Previous investigators have attributed the corona assemblages to isobaric cooling following ultrahigh-temperature metamorphism, but the relatively large size of the coronas and their deformation in the pegmatites suggests that the coronas formed in both the host rocks and the pegmatites during a separate tectonothermal event. The third stage includes two metamorphic events at lower temperatures and moderate to low pressures when surimanite broke down to beryllian cordierite±Al-poor orthopyroxene. The presence of late-formed kyanite and andalusite in the pegmatites is consistent with decompression inferred by other investigators for these two events. Beryllium in the Late Archean pegmatites could have originated from the host granulites, which at "Christmas Point" and Mt. Pardoe have average Be contents of 3.8±2.4ppm and 3.5±1.4ppm, respectively. Beryllium content of host-rock sapphirine is 61 to 616 times whole-rock Be content, implying an important role for this mineral in supplying Be to the anatectic melt. Report Amundsen Bay Antarc* Antarctica East Antarctica Enderby Land Polar geoscience National Institute of Polar Research Repository, Japan East Antarctica Napier ENVELOPE(-58.440,-58.440,-62.167,-62.167) Amundsen Bay ENVELOPE(50.000,50.000,-66.917,-66.917) Pardoe ENVELOPE(50.167,50.167,-67.133,-67.133) Khmara Bay ENVELOPE(48.917,48.917,-67.350,-67.350) Christmas Point ENVELOPE(48.967,48.967,-67.383,-67.383) Zircon Point ENVELOPE(49.100,49.100,-67.383,-67.383) |
institution |
Open Polar |
collection |
National Institute of Polar Research Repository, Japan |
op_collection_id |
ftnipr |
language |
English |
topic |
pegmatite beryllium Antarctica Archean/Archaean |
spellingShingle |
pegmatite beryllium Antarctica Archean/Archaean Edward S. Grew Martin G. Yates Jacques Barbier Charles K. Shearer John W. Sheraton Kazuyuki Shiraishi Yoichi Motoyoshi Granulite-facies beryllium pegmatites in the Napier Complex in Khmara and Amundsen Bays, western Enderby Land, East Antarctica |
topic_facet |
pegmatite beryllium Antarctica Archean/Archaean |
description |
Four granulite-facies beryllium pegmatites of Late Archean age intrude ultrahigh-temperature Napier Complex metapelites in Khmara Bay at "Christmas Point" and "Zircon Point" and in Amundsen Bay on Mt. Pardoe. The pegmatites evolved in three major stages. During the first stage, melt from anatexis of sapphirine-bearing metapelites soon after temperatures peaked during ultrahigh-temperature metamorphism crystallized as pegmatites in inter-boudin spaces during the waning stages of associated deformation. The primary carrier of beryllium in the pegmatites at the time of their intrusion was a sapphirine-group mineral. The second stage is high-temperature metamorphism at moderate pressure, which resulted in reaction of sapphirine with quartz to form corona assemblages of sillimanite+orthopyroxene (or garnet) in the host rocks and sillimanite+garnet+ surinamite in the beryllium pegmatites. Previous investigators have attributed the corona assemblages to isobaric cooling following ultrahigh-temperature metamorphism, but the relatively large size of the coronas and their deformation in the pegmatites suggests that the coronas formed in both the host rocks and the pegmatites during a separate tectonothermal event. The third stage includes two metamorphic events at lower temperatures and moderate to low pressures when surimanite broke down to beryllian cordierite±Al-poor orthopyroxene. The presence of late-formed kyanite and andalusite in the pegmatites is consistent with decompression inferred by other investigators for these two events. Beryllium in the Late Archean pegmatites could have originated from the host granulites, which at "Christmas Point" and Mt. Pardoe have average Be contents of 3.8±2.4ppm and 3.5±1.4ppm, respectively. Beryllium content of host-rock sapphirine is 61 to 616 times whole-rock Be content, implying an important role for this mineral in supplying Be to the anatectic melt. |
format |
Report |
author |
Edward S. Grew Martin G. Yates Jacques Barbier Charles K. Shearer John W. Sheraton Kazuyuki Shiraishi Yoichi Motoyoshi |
author_facet |
Edward S. Grew Martin G. Yates Jacques Barbier Charles K. Shearer John W. Sheraton Kazuyuki Shiraishi Yoichi Motoyoshi |
author_sort |
Edward S. Grew |
title |
Granulite-facies beryllium pegmatites in the Napier Complex in Khmara and Amundsen Bays, western Enderby Land, East Antarctica |
title_short |
Granulite-facies beryllium pegmatites in the Napier Complex in Khmara and Amundsen Bays, western Enderby Land, East Antarctica |
title_full |
Granulite-facies beryllium pegmatites in the Napier Complex in Khmara and Amundsen Bays, western Enderby Land, East Antarctica |
title_fullStr |
Granulite-facies beryllium pegmatites in the Napier Complex in Khmara and Amundsen Bays, western Enderby Land, East Antarctica |
title_full_unstemmed |
Granulite-facies beryllium pegmatites in the Napier Complex in Khmara and Amundsen Bays, western Enderby Land, East Antarctica |
title_sort |
granulite-facies beryllium pegmatites in the napier complex in khmara and amundsen bays, western enderby land, east antarctica |
publisher |
Department of Geological Sciences, University of Maine/Department of Geological Sciences, University of Maine/Department of Chemistry, McMaster University/Institute of Meteoritics, University of New Mexico/Department of Geology, Australian National University/National Institute of Polar Research/National Institute of Polar Research |
publishDate |
2000 |
url |
https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=3064 http://id.nii.ac.jp/1291/00003064/ https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=3064&item_no=1&attribute_id=18&file_no=1 |
long_lat |
ENVELOPE(-58.440,-58.440,-62.167,-62.167) ENVELOPE(50.000,50.000,-66.917,-66.917) ENVELOPE(50.167,50.167,-67.133,-67.133) ENVELOPE(48.917,48.917,-67.350,-67.350) ENVELOPE(48.967,48.967,-67.383,-67.383) ENVELOPE(49.100,49.100,-67.383,-67.383) |
geographic |
East Antarctica Napier Amundsen Bay Pardoe Khmara Bay Christmas Point Zircon Point |
geographic_facet |
East Antarctica Napier Amundsen Bay Pardoe Khmara Bay Christmas Point Zircon Point |
genre |
Amundsen Bay Antarc* Antarctica East Antarctica Enderby Land Polar geoscience |
genre_facet |
Amundsen Bay Antarc* Antarctica East Antarctica Enderby Land Polar geoscience |
op_relation |
https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=3064 http://id.nii.ac.jp/1291/00003064/ AA1130866X Polar geoscience, 13, 1-40(2000-10) https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=3064&item_no=1&attribute_id=18&file_no=1 |
_version_ |
1766367003759607808 |