Evaluating the Influence of Plate Boundary Friction and Mantle Viscosity on Plate Velocities
- Lithospheric plates move over the low-viscosity asthenosphere balancing several forces, which generate plate motions. We use a global 3-D lithosphere-asthenosphere model (SLIM3D) with visco-elasto-plastic rheology coupled to a spectral model of mantle flow at 300 km depth to quantify the influence of intra-plate friction and asthenospheric viscosity on plate velocities. We account for the brittle-ductile deformation at plate boundaries (yield stress) using a plate boundary friction coefficient to predict the present-day plate motion and net rotation of the lithospheric plates. Previous modeling studies have suggested that small friction coefficients (mu < 0.1, yield stress similar to 100 MPa) can lead to plate tectonics in models of mantle convection. Here we show that in order to match the observed present-day plate motion and net rotation, the frictional parameter must be less than 0.05. We obtain a good fit with the magnitude and orientation of the observed plate velocities (NUVEL-1A) in a no-net-rotation (NNR) reference frame withLithospheric plates move over the low-viscosity asthenosphere balancing several forces, which generate plate motions. We use a global 3-D lithosphere-asthenosphere model (SLIM3D) with visco-elasto-plastic rheology coupled to a spectral model of mantle flow at 300 km depth to quantify the influence of intra-plate friction and asthenospheric viscosity on plate velocities. We account for the brittle-ductile deformation at plate boundaries (yield stress) using a plate boundary friction coefficient to predict the present-day plate motion and net rotation of the lithospheric plates. Previous modeling studies have suggested that small friction coefficients (mu < 0.1, yield stress similar to 100 MPa) can lead to plate tectonics in models of mantle convection. Here we show that in order to match the observed present-day plate motion and net rotation, the frictional parameter must be less than 0.05. We obtain a good fit with the magnitude and orientation of the observed plate velocities (NUVEL-1A) in a no-net-rotation (NNR) reference frame with mu < 0.05 and a minimum asthenosphere viscosity of similar to 5 . 10(19) Pas to 10(20) Pas. Our estimates of net rotation (NR) of the lith-osphere suggest that amplitudes similar to 0.1-0.2 (degrees/Ma), similar to most observation-based estimates, can be obtained with asthenosphere viscosity cutoff values of similar to 10(19) Pas to 5 . 10(19) Pas and friction coefficients mu < 0.05.…
Author details: | Anthony Osei TutuORCiD, Stephan SobolevORCiDGND, Bernhard SteinbergerORCiDGND, A. A. Popov, Irina RogozhinaORCiD |
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DOI: | https://doi.org/10.1002/2017GC007112 |
ISSN: | 1525-2027 |
Title of parent work (English): | Geochemistry, geophysics, geosystems |
Publisher: | American Geophysical Union |
Place of publishing: | Washington |
Publication type: | Article |
Language: | English |
Date of first publication: | 2018/02/01 |
Publication year: | 2018 |
Release date: | 2022/01/12 |
Volume: | 19 |
Issue: | 3 |
Number of pages: | 25 |
First page: | 642 |
Last Page: | 666 |
Funding institution: | Helmholtz graduate school GeoSim; Helmholtz Centre Potsdam-GFZ German Research Centre for Geosciences; BMBF German Climate Modeling Initiative PalMod |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Geowissenschaften |
DDC classification: | 5 Naturwissenschaften und Mathematik / 55 Geowissenschaften, Geologie / 550 Geowissenschaften |
Peer review: | Referiert |
Publishing method: | Open Access / Green Open-Access |