Geochemical evolution of the Ivigtut granite, South Greenland: a fluorine-rich "A-type" intrusion
The Ivigtut alkali granite stock lies within the Proterozoic Gardar alkaline igneous province of South Greenland. This small (300 m across) granite body once contained the world's largest body of cryolite, now mined out. The granite surrounding the cryolite body has been extensively metasomatis...
Published in: | Lithos |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
Elsevier BV
2000
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Subjects: | |
Online Access: | https://eprints.gla.ac.uk/874/ https://doi.org/10.1016/S0024-4937(99)00064-X |
Summary: | The Ivigtut alkali granite stock lies within the Proterozoic Gardar alkaline igneous province of South Greenland. This small (300 m across) granite body once contained the world's largest body of cryolite, now mined out. The granite surrounding the cryolite body has been extensively metasomatised by F- and CO2- rich fluids, leading to zonal enrichment in HFSE and REE. Variations in the Rb-Sr and Sm-Nd systematics of the granite can be correlated with the degree of metasomatism. Unaltered granites have highly variable initial Sr-87/Sr-86, and initial epsilon(Nd) ratios of around -3, suggesting formation through crustal contamination of a mantle-derived magma. Metasomatised granites show higher initial epsilon(Nd) ratios, which can be interpreted to suggest that the metasomatic fluid was derived from a mantle source. |
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