Strain Localization at Constant Strain Rate and Changing Stress Conditions: Implications for Plate Boundary Processes in the Upper Mantle
We present results from a natural deformed shear zone in the Turon de Técouère massif of the French Pyrenees that directly addresses the processes involved in strain localization, a topic that has been investigated for the last 40 years by structural geologists. Paleopiezometry indicates that differ...
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MDPI AG
2021-11-01
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| Series: | Minerals |
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| Online Access: | https://www.mdpi.com/2075-163X/11/12/1351 |
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| author | Julie Newman Vasileios Chatzaras Basil Tikoff Jan R. Wijbrans William M. Lamb Martyn R. Drury |
| author_facet | Julie Newman Vasileios Chatzaras Basil Tikoff Jan R. Wijbrans William M. Lamb Martyn R. Drury |
| author_sort | Julie Newman |
| collection | DOAJ |
| description | We present results from a natural deformed shear zone in the Turon de Técouère massif of the French Pyrenees that directly addresses the processes involved in strain localization, a topic that has been investigated for the last 40 years by structural geologists. Paleopiezometry indicates that differential stresses are variable both spatially across the zone, and temporally during exhumation. We have, however, also calculated strain rate, which remains constant despite changes in stress. This result appears to be at odds with recent experimental deformation on monophase (olivine) rocks, which indicate that strain localization occurs dominantly as a result of constant stress. We hypothesize that in the Turon de Técouère massif—and many natural shear zones—strain localization occurs as a result of reactions, which decrease the grain size and promote the activation of grain size sensitive deformation mechanisms. From a tectonics perspective, this study indicates that the deformation rate in a particular plate boundary is relatively uniform. Stress, however, varies to accommodate this deformation. This viewpoint is consistent with deformation at a plate boundary, but it is not the typical way in which we interpret strain localization. |
| first_indexed | 2024-03-10T03:31:02Z |
| format | Article |
| id | doaj.art-1d46881ca5d74ed9ba0f5f5e93f27a01 |
| institution | Directory Open Access Journal |
| issn | 2075-163X |
| language | English |
| last_indexed | 2024-03-10T03:31:02Z |
| publishDate | 2021-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Minerals |
| spelling | doaj.art-1d46881ca5d74ed9ba0f5f5e93f27a012023-11-23T09:41:34ZengMDPI AGMinerals2075-163X2021-11-011112135110.3390/min11121351Strain Localization at Constant Strain Rate and Changing Stress Conditions: Implications for Plate Boundary Processes in the Upper MantleJulie Newman0Vasileios Chatzaras1Basil Tikoff2Jan R. Wijbrans3William M. Lamb4Martyn R. Drury5Department of Geology and Geophysics, Texas A&M University, College Station, TX 77843, USASchool of Geosciences, The University of Sydney, Sydney, NSW 2006, AustraliaDepartment of Geoscience, University of Wisconsin-Madison, Madison, WI 53706, USADepartment of Earth Sciences, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The NetherlandsDepartment of Geology and Geophysics, Texas A&M University, College Station, TX 77843, USADepartment of Earth Sciences, Utrecht University, 3508 TC Utrecht, The NetherlandsWe present results from a natural deformed shear zone in the Turon de Técouère massif of the French Pyrenees that directly addresses the processes involved in strain localization, a topic that has been investigated for the last 40 years by structural geologists. Paleopiezometry indicates that differential stresses are variable both spatially across the zone, and temporally during exhumation. We have, however, also calculated strain rate, which remains constant despite changes in stress. This result appears to be at odds with recent experimental deformation on monophase (olivine) rocks, which indicate that strain localization occurs dominantly as a result of constant stress. We hypothesize that in the Turon de Técouère massif—and many natural shear zones—strain localization occurs as a result of reactions, which decrease the grain size and promote the activation of grain size sensitive deformation mechanisms. From a tectonics perspective, this study indicates that the deformation rate in a particular plate boundary is relatively uniform. Stress, however, varies to accommodate this deformation. This viewpoint is consistent with deformation at a plate boundary, but it is not the typical way in which we interpret strain localization.https://www.mdpi.com/2075-163X/11/12/1351strain localizationperidotitemylonitestressstrain ratePyrenees |
| spellingShingle | Julie Newman Vasileios Chatzaras Basil Tikoff Jan R. Wijbrans William M. Lamb Martyn R. Drury Strain Localization at Constant Strain Rate and Changing Stress Conditions: Implications for Plate Boundary Processes in the Upper Mantle Minerals strain localization peridotite mylonite stress strain rate Pyrenees |
| title | Strain Localization at Constant Strain Rate and Changing Stress Conditions: Implications for Plate Boundary Processes in the Upper Mantle |
| title_full | Strain Localization at Constant Strain Rate and Changing Stress Conditions: Implications for Plate Boundary Processes in the Upper Mantle |
| title_fullStr | Strain Localization at Constant Strain Rate and Changing Stress Conditions: Implications for Plate Boundary Processes in the Upper Mantle |
| title_full_unstemmed | Strain Localization at Constant Strain Rate and Changing Stress Conditions: Implications for Plate Boundary Processes in the Upper Mantle |
| title_short | Strain Localization at Constant Strain Rate and Changing Stress Conditions: Implications for Plate Boundary Processes in the Upper Mantle |
| title_sort | strain localization at constant strain rate and changing stress conditions implications for plate boundary processes in the upper mantle |
| topic | strain localization peridotite mylonite stress strain rate Pyrenees |
| url | https://www.mdpi.com/2075-163X/11/12/1351 |
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