(Th+U)-Pb monazite ages from Al-Mg-rich metapelites, Rauer Group, east Antarctica
The age of high-temperature granulite-facies metamorphism (>~800–850 °C) in the Rauer Group, Prydz Bay, east Antarctica, is relevant for establishing the metamorphic and temporal architecture of the Prydz Bay mobile belt. Monazites within Al-Mg-rich granulite-facies metapelites give an overall ta...
Published in: | Contributions to Mineralogy and Petrology |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Springer
2003
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Subjects: | |
Online Access: | http://hdl.handle.net/2440/34307 https://doi.org/10.1007/s00410-003-0497-3 |
Summary: | The age of high-temperature granulite-facies metamorphism (>~800–850 °C) in the Rauer Group, Prydz Bay, east Antarctica, is relevant for establishing the metamorphic and temporal architecture of the Prydz Bay mobile belt. Monazites within Al-Mg-rich granulite-facies metapelites give an overall tanh-estimated Pan-African age of ~511±4 Ma (2) using in-situ electron microprobe-based (Th+U)-Pb chronology, consistent with existing U-Pb zircon geochronology from the Rauer Group and Prydz Bay. Monazite occurs primarily within cordierite-bearing coronae and symplectic mineral reaction textures, and also within biotite. Pan-African granulite-facies metamorphism is preferred as responsible for the development of the cordierite-bearing microstructures, and probably (peak) coarse-grained assemblages, constrained using an integrated geologic, geochronologic and metamorphic framework. Thus, Pan-African granulite-facies metamorphism affected the Rauer Group, within the Prydz Bay mobile belt. Moreover, integrated monazite geochronology may be used to decipher the temporal metamorphic histories of potentially complex high-temperature terrains. D. E. Kelsey, R. Powell, C. J. L. Wilson and D. A. Steele |
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