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The global age distribution of granitic pegmatites

Canadian Mineralogist

By:
and
DOI: 10.3749/canmin.52.2.183

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Abstract

An updated global compilation of 377 new and previously published ages indicates that granitic pegmatites range in age from Mesoarchean to Neogene and have a semi-periodic age distribution. Undivided granitic pegmatites show twelve age maxima: 2913, 2687, 2501, 1853, 1379, 1174, 988, 525, 483, 391, 319, and 72 Ma. These peaks correspond broadly with various proxy records of supercontinent assembly, including the age distributions of granites, detrital zircon grains, and passive margins. Lithium-cesium-tantalum (LCT) pegmatites have a similar age distribution to the undivided granitic pegmatites, with maxima at 2638, 1800, 962, 529, 485, 371, 309, and 274 Ma. Lithium and Ta resources in LCT pegmatites are concentrated in the Archean and Phanerozoic. While there are some Li resources from the Proterozoic, the dominantly bimodal distribution of resources is particularly evident for Ta. This distribution is similar to that of orogenic gold deposits, and has been interpreted to reflect the preservation potential of the orogenic belts where these deposits are formed. Niobium-yttrium-fluorine (NYF) pegmatites show similar age distributions to LCT pegmatites, but with a strong maximum at ca. 1000 Ma.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
The global age distribution of granitic pegmatites
Series title:
Canadian Mineralogist
DOI:
10.3749/canmin.52.2.183
Volume
52
Issue:
2
Year Published:
2014
Language:
English
Publisher:
Mineralogical Association of Canada
Contributing office(s):
Alaska Science Center
Description:
8 p.
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Canadian Mineralogist
First page:
183
Last page:
190