England, PC, Houseman, GA orcid.org/0000-0003-2907-8840 and Nocquet, JM (2016) Constraints from GPS measurements on the dynamics of deformation in Anatolia and the Aegean. Journal of Geophysical Research: Solid Earth, 121 (12). pp. 8888-8916. ISSN 2169-9313
Abstract
We estimate the strength of the lithosphere in Anatolia and the Aegean, and the boundary forces acting upon it, using a dynamical model that treats the lithosphere as a thin fluid sheet deforming in response to variations in gravitational potential energy. This model has one free material parameter, the power law exponent, n, of the vertically averaged rheology of the lithosphere, and two parameters that specify the forces per unit length applied to its edges. Solutions to this model that best fit the velocities of 346 reliable GPS sites require an effective viscosity of the lithosphere of 1022 to 1021 Pa s at strain rates of 10 to 100 nanostrain per year. The best-fitting force at the Arabia-Anatolia boundary is consistent with the lithostatic pressure due to the high topography there, and the force at the Nubia-Aegean boundary is consistent with the contrast in lithostatic pressure across that boundary. No additional force, from “slab rollback” or basal tractions due to convection in the mantle, is required to explain the observations. These results are supported by scaling relations derived from approximate analytical solutions. The inverse relationship between the viscosity of the lithosphere and deviatoric stress produces strong slowly deforming regions in the Southern Aegean and Central Anatolia whose motions resemble those of microplates. The distribution of geodetic strain rates within the region, and the partitioning between normal and strike-slip faulting, are explained by the interplay between boundary conditions, internal variations in gravitational potential energy, and the power law rheology of the lithosphere.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2016 American Geophysical Union. All rights reserved. This is an author produced version of a paper published in Journal of Geophysical Research. Solid Earth. To view the published open abstract, go tohttps://doi.org/10.1002/2016JB013382 . Uploaded with permission from the publisher. |
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) > Inst of Geophysics and Tectonics (IGT) (Leeds) |
Funding Information: | Funder Grant number NERC No External Reference NERC NE/I028017/1 NERC NE/K010867/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 22 Nov 2016 11:12 |
Last Modified: | 29 Jul 2017 22:20 |
Published Version: | https://doi.org/10.1002/2016JB013382 |
Status: | Published |
Publisher: | American Geophysical Union |
Identification Number: | 10.1002/2016JB013382 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:108047 |