Coupling model with poroelastic and viscoelastic

PyLith
1

Dear all,

I would like to use PyLith to simulate earthquake deformation with a coupled model consisting of a poroelastic crust and a viscoelastic mantle. I have already worked through the poroelastic example (2D Outer-Rise Hydration Using Poroelasticity) and the viscoelastic example (Subduction Zone (3D)) to learn the general workflow in PyLith.

Is it feasible to combine these two setups by assigning a poroelastic rheology to the crust and a viscoelastic rheology to the mantle within the same model? In other words, can I configure the model by following the structure of these two examples and simply defining different material models for different regions?

If this is possible, are there any additional considerations or common pitfalls that are not covered in the example problems (e.g., interface conditions, boundary conditions, time stepping, solver settings, or parameter choices) that I should pay attention to when coupling poroelastic and viscoelastic materials?

All the best.

Yawen she

2

It is not currently possible to combine poroelasticity and elasticity materials in the same simulation, because PyLith currently assumes the same governing equation is used for the entire domain. Grant Block has been working on adding viscoelastic bulk rheologies to the poroelasticity governing equation, but he is not yet finished. Once this is implemented, then it will be possible to model a poroelastic crust (with a linear elastic bulk rheology) and a poroelastic mantle (with a viscoelastic bulk rheology); the poroelastic parameters could be adjusted to minimize the poroelastic effects in the mantle.

3

Thanks for your explanations.