EGU2020-9861
https://doi.org/10.5194/egusphere-egu2020-9861
EGU General Assembly 2020
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Structural controls on stresses and deformations in a large-scale lithospheric shell

Sergei Medvedev and Alexander Minakov
Sergei Medvedev and Alexander Minakov
  • University of Oslo, Earth Sciences, CEED, Oslo, Norway (sergeim@geo.uio.no)

It is well-accepted that stresses and deformation are controlled by active forces, such as tractions applied along lateral boundaries and base of the lithosphere and body forces raised from density heterogeneities within or below the lithosphere. Here we analyze how structure, geometry and strength distribution, of the Earth crust and upper mantle can affect the pattern of stresses and deformation. As an application example, we use the North Atlantic realm which characterized by strong topography and rheological variations and subjected to active forces from, e.g., the Iceland hot spot. We conduct a series of numerical experiments modelling the lithosphere as an elastic shell of altering geometries influenced by various mechanisms. The first set of experiments demonstrates that lithosphere, as a part of the spherical Earth, is structurally stronger than the flat lithosphere if boundary moments applied. An application of more realistic, topography derived, geometry of the lithospheric shell in the second set of experiments demonstrates the importance of strong topography changes, for example along continent-ocean transition, as a concentrator of bending stresses and deformations. In the third set, we show how viscous properties of the sub-lithospheric asthenosphere may control the lateral extent of the membrane stresses in the lithosphere.

How to cite: Medvedev, S. and Minakov, A.: Structural controls on stresses and deformations in a large-scale lithospheric shell, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9861, https://doi.org/10.5194/egusphere-egu2020-9861, 2020

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