Ion microprobe (SHRIMP) dates complex granulite from Santa Catarina, southern Brazil
Fuente:
Redalyc
Enregistré dans:
| Auteur principal: | |
|---|---|
| Format: | Artículo científico |
| Langue: | en |
| Publié: |
Academia Brasileira de Ciências
2000
|
| Sujets: | |
| Accès en ligne: | |
| Tags: |
Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
|
| _version_ | 1876444198905839616 |
|---|---|
| author | Léo A. Hartmann |
| author_facet | Léo A. Hartmann |
| contents | Ion microprobe (SHRIMP) dates complex granulite from Santa Catarina, southern Brazil Léo A. Hartmann Neal J. McNaughton João O. S. Santos Marcos A. Z. Vasconcellos Luiz C. Dasilva Multidisciplinaria (Ciencias Naturales y Exactas) SHRIMP Brazil zircon granulites symplectites Complex polymetamorphic granulites have been dated in the Santa Catarina granulite complex of southernBrazil through SHRIMP study of zircon. This complex is dominated by intermediate-acid plutonic rocksand contains small volumes of mafic and ultramafic rocks, and minor quartzite and banded iron formation.Porphyroblasts of orthopyroxene, clinopyroxene and plagioclase in mafic and acid rocks are interpreted asmagmatic remnants in a volumetrically dominant granoblastic aggregate (M1) of the same minerals andhornblende. Hornblende formed during a laterM2 metamorphic event constitutes rims around pyroxene, butthe hornblende is also rimmed by granoblastic simplectites of orthopyroxene, clinopyroxene, hornblende andplagioclase in a second granulite facies event (M3). Chlorite and epidote occur in shear zones (M4). Thisgranulite terrain is part of a Neoproterozoic craton, because it was little affected by the Brasiliano Cycle. Thetwo granulite-facies events (M1 andM3) are dated by U/Pb zircon SHRIMP at about 2.68 and 2.17 Ga, whilethe magmatic protoliths formed at about 2.72 Ga. The amphibolite facies event (M2) probably occurred closeto the 2.17 Ga granulitic metamorphism. 2000 artículo científico 0001-3765 https://www.redalyc.org/articulo.oa?id=32772407 en http://www.redalyc.org/revista.oa?id=327 Anais da Academia Brasileira de Ciências application/pdf Academia Brasileira de Ciências Anais da Academia Brasileira de Ciências (Brasil) Num.4 Vol.72 |
| format | Artículo científico |
| id | redalyc_32772407 |
| institution | Redalyc |
| language | en |
| publishDate | 2000 |
| publisher | Academia Brasileira de Ciências |
| spellingShingle | Ion microprobe (SHRIMP) dates complex granulite from Santa Catarina, southern Brazil Léo A. Hartmann Multidisciplinaria (Ciencias Naturales y Exactas) SHRIMP Brazil zircon granulites symplectites Ion microprobe (SHRIMP) dates complex granulite from Santa Catarina, southern Brazil Léo A. Hartmann Neal J. McNaughton João O. S. Santos Marcos A. Z. Vasconcellos Luiz C. Dasilva Multidisciplinaria (Ciencias Naturales y Exactas) SHRIMP Brazil zircon granulites symplectites Complex polymetamorphic granulites have been dated in the Santa Catarina granulite complex of southernBrazil through SHRIMP study of zircon. This complex is dominated by intermediate-acid plutonic rocksand contains small volumes of mafic and ultramafic rocks, and minor quartzite and banded iron formation.Porphyroblasts of orthopyroxene, clinopyroxene and plagioclase in mafic and acid rocks are interpreted asmagmatic remnants in a volumetrically dominant granoblastic aggregate (M1) of the same minerals andhornblende. Hornblende formed during a laterM2 metamorphic event constitutes rims around pyroxene, butthe hornblende is also rimmed by granoblastic simplectites of orthopyroxene, clinopyroxene, hornblende andplagioclase in a second granulite facies event (M3). Chlorite and epidote occur in shear zones (M4). Thisgranulite terrain is part of a Neoproterozoic craton, because it was little affected by the Brasiliano Cycle. Thetwo granulite-facies events (M1 andM3) are dated by U/Pb zircon SHRIMP at about 2.68 and 2.17 Ga, whilethe magmatic protoliths formed at about 2.72 Ga. The amphibolite facies event (M2) probably occurred closeto the 2.17 Ga granulitic metamorphism. 2000 artículo científico 0001-3765 https://www.redalyc.org/articulo.oa?id=32772407 en http://www.redalyc.org/revista.oa?id=327 Anais da Academia Brasileira de Ciências application/pdf Academia Brasileira de Ciências Anais da Academia Brasileira de Ciências (Brasil) Num.4 Vol.72 |
| title | Ion microprobe (SHRIMP) dates complex granulite from Santa Catarina, southern Brazil |
| topic | Multidisciplinaria (Ciencias Naturales y Exactas) SHRIMP Brazil zircon granulites symplectites |
| url | https://www.redalyc.org/articulo.oa?id=32772407 |