switch_topoest and dens_infill

[mberry28]

Hi Daniel,

I wanted to get some clarity on how switch_topoest works. I have looked at the code and it's not perfectly clear what is happening, and when would it be implemented. It seems that the weight of the sediment infill material should be added to the deflection of the model. Does this happen when we, for example, form a basin and fill it with fluvial sediments?

Thanks

[danigeos]

Good question, since this is somewhat confusing.
switch_topoest is a parameter in the PRM file (and also available as topoest 1 in the UNIT files) that allows to calculate subsidence as a result of a known (fixed) topography.

In the figure attached, the model in the left uses switch_topoest = 1, with the *1.UNIT defining only the triangle in the center (rho_c). In this mode, the load stays fixed on top of the previous topography, and the deflection (subsidence) of the plate is filled with "rho_relleno" (called dens_infill in TISC).

On the right side, a model using switch_topoest = 0, where a (larger) load subsides with the plate. In this case, the flexural basins are gradually infilled with a sedimentation model.

If you don't want to model the gradual infill of the basin with an erosion model, and you are just interested in the final (present?) stage, then you may want to use this.