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Indirect dating of tectonic events by Rb—Sr analysis of syntectonic garnets: an example from schists of the Seve Nappe, central Scandinavian Caledomdes

Published online by Cambridge University Press:  01 May 2009

A. P. S. Reymer
Affiliation:
Institute of Earth Sciences, Department of Geology, The Hebrew University, Jerusalem, Israel

Summary

Rb-Sr analyses of syntectonic single-crystal garnets from the Svartsobacken and Dikanas schist units of the Seve Nappe, Scandinavian Caledonides, show systematic differences. One group yields a Precambrian age spectrum consistent with that given by whole-rock analyses; the other group gives Caledonian ages similar to those given by mica analyses. It follows that the tectonic events reflected in the garnet inclusion patterns are also of different ages and, subject to certain limitations, the method can be used to provide a clearer interpretation of the deformational and metamorphic history of the rock.

Type
Articles
Copyright
Copyright © Cambridge University Press 1982

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