~990 Ma peak granulitic metamorphism and amalgamation of Oaxaquia, Mexico: U–Pb zircon geochronological and common Pb isotopic data

Fuente: Redalyc
Enregistré dans:
Détails bibliographiques
Auteur principal: J. Duncan Keppie
Format: Artículo científico
Langue:en
Publié: Universidad Nacional Autónoma de México 2004
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1876449900752797696
author J. Duncan Keppie
author_facet J. Duncan Keppie
contents ~990 Ma peak granulitic metamorphism and amalgamation of Oaxaquia, Mexico: U–Pb zircon geochronological and common Pb isotopic data J. Duncan Keppie Kenneth L. Cameron Robert Lopez Luigi A. Solari Fernando Ortega Gutiérrez Ciencias de la Tierra Oaxaquia Pb geochronology Grenvillian Orogeny granulite metamorphism The ~1 Ga Oaxacan Complex is the largest exposure of the Oaxaquia terrane of Mexico. Microprobeanalysis of co-existing ortho- and clino-pyroxene, garnet, ilmenite and plagioclase indicate metamorphicconditions of 735 ± 5° C and 7.7 ± 0.1 kbar in the granulite facies, which was dated between ~998 and~979 Ma using U–Pb isotopic analyses of zircon populations. Peak temperatures >800° C and isobariccooling are indicated by the sporadic presence of sapphirine in metasediment and garnet–cordierite–sillimanite–K-feldspar–rutile assemblages, and garnet coronas around pyroxene and titanomagnetite.Common Pb isotopes from acid-leached whole-rock samples define an errorchron that intersects theStacey/Kramers crustal growth curve at 1,187 ± 63 Ma indicating a major crust-forming event at thistime, and suggesting that the granulite facies metamorphism did not significantly reset the common Pbisotopic composition. These data are comparable with those from other ~1 Ga inliers in Mexico and isconsistent with a single Oaxaquia terrane by ~1 Ga. 2004 artículo científico 1026-8774 https://www.redalyc.org/articulo.oa?id=57221202 en http://www.redalyc.org/revista.oa?id=572 Revista Mexicana de Ciencias Geológicas application/pdf Universidad Nacional Autónoma de México Revista Mexicana de Ciencias Geológicas (México) Num.2 Vol.21
format Artículo científico
id redalyc_57221202
institution Redalyc
language en
publishDate 2004
publisher Universidad Nacional Autónoma de México
spellingShingle ~990 Ma peak granulitic metamorphism and amalgamation of Oaxaquia, Mexico: U–Pb zircon geochronological and common Pb isotopic data
J. Duncan Keppie
Ciencias de la Tierra
Oaxaquia
Pb geochronology
Grenvillian Orogeny
granulite metamorphism
~990 Ma peak granulitic metamorphism and amalgamation of Oaxaquia, Mexico: U–Pb zircon geochronological and common Pb isotopic data J. Duncan Keppie Kenneth L. Cameron Robert Lopez Luigi A. Solari Fernando Ortega Gutiérrez Ciencias de la Tierra Oaxaquia Pb geochronology Grenvillian Orogeny granulite metamorphism The ~1 Ga Oaxacan Complex is the largest exposure of the Oaxaquia terrane of Mexico. Microprobeanalysis of co-existing ortho- and clino-pyroxene, garnet, ilmenite and plagioclase indicate metamorphicconditions of 735 ± 5° C and 7.7 ± 0.1 kbar in the granulite facies, which was dated between ~998 and~979 Ma using U–Pb isotopic analyses of zircon populations. Peak temperatures >800° C and isobariccooling are indicated by the sporadic presence of sapphirine in metasediment and garnet–cordierite–sillimanite–K-feldspar–rutile assemblages, and garnet coronas around pyroxene and titanomagnetite.Common Pb isotopes from acid-leached whole-rock samples define an errorchron that intersects theStacey/Kramers crustal growth curve at 1,187 ± 63 Ma indicating a major crust-forming event at thistime, and suggesting that the granulite facies metamorphism did not significantly reset the common Pbisotopic composition. These data are comparable with those from other ~1 Ga inliers in Mexico and isconsistent with a single Oaxaquia terrane by ~1 Ga. 2004 artículo científico 1026-8774 https://www.redalyc.org/articulo.oa?id=57221202 en http://www.redalyc.org/revista.oa?id=572 Revista Mexicana de Ciencias Geológicas application/pdf Universidad Nacional Autónoma de México Revista Mexicana de Ciencias Geológicas (México) Num.2 Vol.21
title ~990 Ma peak granulitic metamorphism and amalgamation of Oaxaquia, Mexico: U–Pb zircon geochronological and common Pb isotopic data
topic Ciencias de la Tierra
Oaxaquia
Pb geochronology
Grenvillian Orogeny
granulite metamorphism
url https://www.redalyc.org/articulo.oa?id=57221202