Evidence of Metasomatism in the Lowest Petrographic Types Inferred from A Na(-), K, Rich Rim Around A LEW 86018 (L3.1) Chondrule
Ordinary chondrites (OCs) represent the most abundant extraterrestrial materials and also record the widest range of alteration of primary, pristine minerals of early Solar system material available for study. Relatively few investigations, however, address: (1) the role of fluid alteration, and (2)...
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ftnasantrs:oai:casi.ntrs.nasa.gov:20150006011 2023-05-15T13:33:56+02:00 Evidence of Metasomatism in the Lowest Petrographic Types Inferred from A Na(-), K, Rich Rim Around A LEW 86018 (L3.1) Chondrule Ross, Daniel Kent Mishra, Ritesh Kumar Marhas, Kuljeet Kaur Simon, Justin I. Unclassified, Unlimited, Publicly available May 3, 2015 application/pdf http://hdl.handle.net/2060/20150006011 unknown Document ID: 20150006011 http://hdl.handle.net/2060/20150006011 Copyright, Distribution as joint owner in the copyright CASI Lunar and Planetary Science and Exploration Geosciences (General) JSC-CN-33026 2015 AGU/GAC/MAC/CGU Joint Assembly; 3-7 May 2015; Montreal; Canada 2015 ftnasantrs 2019-07-21T00:14:57Z Ordinary chondrites (OCs) represent the most abundant extraterrestrial materials and also record the widest range of alteration of primary, pristine minerals of early Solar system material available for study. Relatively few investigations, however, address: (1) the role of fluid alteration, and (2) the relationship between thermal metamorphism and metasomatism in OCs, issues that have been extensively studied in many other meteorite groups e.g., CV, CO, CR, and enstatite chondrites. Detailed elemental abundances profiles across individual chondrules, and mineralogical studies of Lewis Hills (LEW) 86018 (L3.1), an unequilibrated ordinary chondrite (UOC) of low petrographic type of 3.1 returned from Antarctica, provide evidence of extensive alteration of primary minerals. Some chondrules have Na(-), K(-), rich rims surrounded by nepheline, albite, and sodalite-like Na(-), Cl(-), Al-rich secondary minerals in the near vicinity within the matrices. Although, limited evidences of low temperature (approximately 250 C) fluid-assisted alteration of primary minerals to phyllosilicates, ferroanolivine, magnetite, and scapolite have been reported in the lowest grades (less than 3.2) Semarkona (LL3.00) and Bishunpur (LL3.10), alkali-rich secondary mineralization has previously only been seen in higher grade greater than 3.4 UOCs. This preliminary result suggests highly localized metamorphism in UOCs and widens the range of alteration in UOCs and complicates classification of petrographic type and extent of thermal metamorphism or metasomatism. The work in progress will document the micro-textures, geochemistry (Ba, Ca, REE), and isotopic composition (oxygen, Al(-)- 26 Mg-26) of mineral phases in chondrules and adjoining objects to help us understand the formation scenario and delineate possible modes of metamorphism in UOCs. Other/Unknown Material Antarc* Antarctica NASA Technical Reports Server (NTRS) |
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NASA Technical Reports Server (NTRS) |
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topic |
Lunar and Planetary Science and Exploration Geosciences (General) |
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Lunar and Planetary Science and Exploration Geosciences (General) Ross, Daniel Kent Mishra, Ritesh Kumar Marhas, Kuljeet Kaur Simon, Justin I. Evidence of Metasomatism in the Lowest Petrographic Types Inferred from A Na(-), K, Rich Rim Around A LEW 86018 (L3.1) Chondrule |
topic_facet |
Lunar and Planetary Science and Exploration Geosciences (General) |
description |
Ordinary chondrites (OCs) represent the most abundant extraterrestrial materials and also record the widest range of alteration of primary, pristine minerals of early Solar system material available for study. Relatively few investigations, however, address: (1) the role of fluid alteration, and (2) the relationship between thermal metamorphism and metasomatism in OCs, issues that have been extensively studied in many other meteorite groups e.g., CV, CO, CR, and enstatite chondrites. Detailed elemental abundances profiles across individual chondrules, and mineralogical studies of Lewis Hills (LEW) 86018 (L3.1), an unequilibrated ordinary chondrite (UOC) of low petrographic type of 3.1 returned from Antarctica, provide evidence of extensive alteration of primary minerals. Some chondrules have Na(-), K(-), rich rims surrounded by nepheline, albite, and sodalite-like Na(-), Cl(-), Al-rich secondary minerals in the near vicinity within the matrices. Although, limited evidences of low temperature (approximately 250 C) fluid-assisted alteration of primary minerals to phyllosilicates, ferroanolivine, magnetite, and scapolite have been reported in the lowest grades (less than 3.2) Semarkona (LL3.00) and Bishunpur (LL3.10), alkali-rich secondary mineralization has previously only been seen in higher grade greater than 3.4 UOCs. This preliminary result suggests highly localized metamorphism in UOCs and widens the range of alteration in UOCs and complicates classification of petrographic type and extent of thermal metamorphism or metasomatism. The work in progress will document the micro-textures, geochemistry (Ba, Ca, REE), and isotopic composition (oxygen, Al(-)- 26 Mg-26) of mineral phases in chondrules and adjoining objects to help us understand the formation scenario and delineate possible modes of metamorphism in UOCs. |
format |
Other/Unknown Material |
author |
Ross, Daniel Kent Mishra, Ritesh Kumar Marhas, Kuljeet Kaur Simon, Justin I. |
author_facet |
Ross, Daniel Kent Mishra, Ritesh Kumar Marhas, Kuljeet Kaur Simon, Justin I. |
author_sort |
Ross, Daniel Kent |
title |
Evidence of Metasomatism in the Lowest Petrographic Types Inferred from A Na(-), K, Rich Rim Around A LEW 86018 (L3.1) Chondrule |
title_short |
Evidence of Metasomatism in the Lowest Petrographic Types Inferred from A Na(-), K, Rich Rim Around A LEW 86018 (L3.1) Chondrule |
title_full |
Evidence of Metasomatism in the Lowest Petrographic Types Inferred from A Na(-), K, Rich Rim Around A LEW 86018 (L3.1) Chondrule |
title_fullStr |
Evidence of Metasomatism in the Lowest Petrographic Types Inferred from A Na(-), K, Rich Rim Around A LEW 86018 (L3.1) Chondrule |
title_full_unstemmed |
Evidence of Metasomatism in the Lowest Petrographic Types Inferred from A Na(-), K, Rich Rim Around A LEW 86018 (L3.1) Chondrule |
title_sort |
evidence of metasomatism in the lowest petrographic types inferred from a na(-), k, rich rim around a lew 86018 (l3.1) chondrule |
publishDate |
2015 |
url |
http://hdl.handle.net/2060/20150006011 |
op_coverage |
Unclassified, Unlimited, Publicly available |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_source |
CASI |
op_relation |
Document ID: 20150006011 http://hdl.handle.net/2060/20150006011 |
op_rights |
Copyright, Distribution as joint owner in the copyright |
_version_ |
1766047171453386752 |