Torvela, T orcid.org/0000-0003-1539-8755 and Kurhila, M (2022) Timing of syn-orogenic, high-grade transtensional shear zone formation in the West Uusimaa Complex, Finland. Bulletin of the Geological Society of Finland. ISSN 0367-5211
Abstract
We present zircon and titanite U-Pb ages from granulite-facies transtensional shear zones and a greenschist facies strike-slip shear zone in the Karkkila-Vihti area, West Uusimaa. The zircon rim and titanite ages of c. 1815−1820 Ma from the transtensional shear zones constrain the evolution of the orogenic deformation from compression-dominated to syn-compressional lateral-escape within this part of the Fennoscandian shield while the zircon rim and titanite ages of 1790−1800 Ma give the timing of the late- to post-orogenic low-grade reactivation of the large-scale Somero-Karkkila fault zone. The new age data further constrain the timing of the changes in the crustal deformation style during orogenesis from i) compression-dominated to combined transpression - lateral stretching and escape, to ii) the late- to post-orogenic transition into retrograde conditions.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | This article is protected by copyright. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0) (https://creativecommons.org/licenses/by-nc/4.0/) |
Keywords: | West Uusimaa Complex, transtension, shear zones, age determinations, migmatite |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Institute for Applied Geosciences (IAG) (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 30 Jun 2022 13:44 |
Last Modified: | 30 Jun 2022 13:44 |
Status: | Published |
Publisher: | The Geological Society of Finland |
Identification Number: | 10.17741/bgsf/94.1.001 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:188520 |