[CIG-SHORT] Gravity on Large/Heterogeneous Meshes

[Scott Henderson]

Hello,

I've been modifying the step16.cfg tutorial for a larger mesh. If I increase the domain size from 6x6x4 to 200x200x100km, and change the initial_stress.spatialdb to correspond to the new lithostatic stress at the base of the mesh (-2451637500Pa). I'm finding that the elastic solution has ~2 cm of subsidence at the surface, but I expect zero displacement. This appears to be independent of element size.

Also, if I have non-uniform density in the mesh (for example an embedded weak layer or arbitrary shape), how might I set up the initial stresses to compensate for gravity? I'm guessing that the only way to go about this is run the solution without initial stresses, extract the stress values at a few points through each material, then set up separate spatial databases for each material for the next run?

Thanks,
Scott

step16_1 = same settings as step16, but larger mesh
step16_2 = just elastic solution

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