Petrology and phase equilibrium modeling of spinel-sapphirine-bearing mafic granulite from Akarui Point, Lützow-Holm Complex, East Antarctica: Implications for the P-T path
We report new petrological and P-T data for spinel-sapphirine-bearing mafic granulite from Akarui Point in the upper amphibolite- to granulite-facies transitional zone of the Lützow-Holm Complex (LHC), East Antarctica, and provide unequivocal evidence for extreme crustal metamorphism possibly associ...
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| Format: | Journal Article |
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Sasaki Printing & Publishing Co. Ltd
2013
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| Online Access: | http://hdl.handle.net/20.500.11937/42726 |
| _version_ | 1848756498806603776 |
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| author | Iwamura, S. Tsunogae, T. Kato, M. Koizumi, T. Dunkley, Daniel |
| author_facet | Iwamura, S. Tsunogae, T. Kato, M. Koizumi, T. Dunkley, Daniel |
| author_sort | Iwamura, S. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | We report new petrological and P-T data for spinel-sapphirine-bearing mafic granulite from Akarui Point in the upper amphibolite- to granulite-facies transitional zone of the Lützow-Holm Complex (LHC), East Antarctica, and provide unequivocal evidence for extreme crustal metamorphism possibly associated with the collisional orogeny during the Neoproterozoic. The reaction microstructures in the rock suggest the stability of the prograde pargasite + garnet + orthopyroxene + plagioclase + hematite assemblage followed by the formation of plagioclase + orthopyroxene + spinel + sapphirine symplectite after garnet. The application of mineral equilibrium modeling on the mafic granulite in the system NCFMASHTO yields a prograde condition of 11-12 kbar and ~ 900 °C, followed by decompression to the peak stage (Pgs + Pl + Opx + Spl ± H2O) of 5-6 kbar and 900-920 °C, and subsequent cooling to less than 890 °C, possibly along a clockwise P-T path. The high-temperature and possibly ultrahigh-temperature condition observed at Akarui Point might reflect an effect of a local thermal event or the presence of an exotic crustal block within the LHC, which are essentially associated with the complex collisional evolution of this region during the assembly of Gondwana. |
| first_indexed | 2025-11-14T09:13:10Z |
| format | Journal Article |
| id | curtin-20.500.11937-42726 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T09:13:10Z |
| publishDate | 2013 |
| publisher | Sasaki Printing & Publishing Co. Ltd |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-427262017-09-13T14:24:47Z Petrology and phase equilibrium modeling of spinel-sapphirine-bearing mafic granulite from Akarui Point, Lützow-Holm Complex, East Antarctica: Implications for the P-T path Iwamura, S. Tsunogae, T. Kato, M. Koizumi, T. Dunkley, Daniel Neoproterozoic-Cambrian Pseudosection NCFMASHTO system East Antarctica Granulite We report new petrological and P-T data for spinel-sapphirine-bearing mafic granulite from Akarui Point in the upper amphibolite- to granulite-facies transitional zone of the Lützow-Holm Complex (LHC), East Antarctica, and provide unequivocal evidence for extreme crustal metamorphism possibly associated with the collisional orogeny during the Neoproterozoic. The reaction microstructures in the rock suggest the stability of the prograde pargasite + garnet + orthopyroxene + plagioclase + hematite assemblage followed by the formation of plagioclase + orthopyroxene + spinel + sapphirine symplectite after garnet. The application of mineral equilibrium modeling on the mafic granulite in the system NCFMASHTO yields a prograde condition of 11-12 kbar and ~ 900 °C, followed by decompression to the peak stage (Pgs + Pl + Opx + Spl ± H2O) of 5-6 kbar and 900-920 °C, and subsequent cooling to less than 890 °C, possibly along a clockwise P-T path. The high-temperature and possibly ultrahigh-temperature condition observed at Akarui Point might reflect an effect of a local thermal event or the presence of an exotic crustal block within the LHC, which are essentially associated with the complex collisional evolution of this region during the assembly of Gondwana. 2013 Journal Article http://hdl.handle.net/20.500.11937/42726 10.2465/jmps.130621a Sasaki Printing & Publishing Co. Ltd restricted |
| spellingShingle | Neoproterozoic-Cambrian Pseudosection NCFMASHTO system East Antarctica Granulite Iwamura, S. Tsunogae, T. Kato, M. Koizumi, T. Dunkley, Daniel Petrology and phase equilibrium modeling of spinel-sapphirine-bearing mafic granulite from Akarui Point, Lützow-Holm Complex, East Antarctica: Implications for the P-T path |
| title | Petrology and phase equilibrium modeling of spinel-sapphirine-bearing mafic granulite from Akarui Point, Lützow-Holm Complex, East Antarctica: Implications for the P-T path |
| title_full | Petrology and phase equilibrium modeling of spinel-sapphirine-bearing mafic granulite from Akarui Point, Lützow-Holm Complex, East Antarctica: Implications for the P-T path |
| title_fullStr | Petrology and phase equilibrium modeling of spinel-sapphirine-bearing mafic granulite from Akarui Point, Lützow-Holm Complex, East Antarctica: Implications for the P-T path |
| title_full_unstemmed | Petrology and phase equilibrium modeling of spinel-sapphirine-bearing mafic granulite from Akarui Point, Lützow-Holm Complex, East Antarctica: Implications for the P-T path |
| title_short | Petrology and phase equilibrium modeling of spinel-sapphirine-bearing mafic granulite from Akarui Point, Lützow-Holm Complex, East Antarctica: Implications for the P-T path |
| title_sort | petrology and phase equilibrium modeling of spinel-sapphirine-bearing mafic granulite from akarui point, lützow-holm complex, east antarctica: implications for the p-t path |
| topic | Neoproterozoic-Cambrian Pseudosection NCFMASHTO system East Antarctica Granulite |
| url | http://hdl.handle.net/20.500.11937/42726 |