Articles | Volume 35, issue 4
https://doi.org/10.5194/ejm-35-645-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/ejm-35-645-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Aug 2023
Research article |
| 15 Aug 2023
| 15 Aug 2023
Provenance, protolith and metamorphic ages of jadeite-bearing orthogneiss and host paragneiss at Tavagnasco, the Sesia Zone, Lower Aosta Valley, Italy
Department of Earth and Environmental Sciences, University of Iowa,
Iowa City, IA 52242, USA
William C. McClelland
Department of Earth and Environmental Sciences, University of Iowa,
Iowa City, IA 52242, USA
Simon Schorn
NAWI Graz Geocenter, University of Graz, 8010 Graz, Austria
Roberto Compagnoni
Department of Earth Sciences, University of Torino, 10125 Turin,
Italy
Matthew A. Coble
Department of Geological Sciences, Stanford-USGS Ion Microprobe
Laboratory, Stanford, CA 94305, USA
Department of Environmental Chemistry, GNS Science, Avalon, 5010, New Zealand
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Short summary
We show that metamorphosed sedimentary rocks in the Western Alps have a detrital zircon signature that connects them to the Adrian plate along the Gondwana margin. We used zircon to learn that a jadeite-bearing orthogneiss intruded into these strata in the Ordovician (at ~460 Ma) and was metamorphosed at high pressure during early Alpine subduction of Adria beneath Europe at ~78 Ma. Our results are consistent with the complex subduction of Adria before full-on collision with the European plate.
We show that metamorphosed sedimentary rocks in the Western Alps have a detrital zircon...
