Meshing#
Overview#
AxiSEM3D makes use of the stand-alone mesher SalvusMeshLite. See the Mesher Installation Instructions on information how to install.
Usage#
To create a self-explanatory input.yaml YAML file, run:
$ python -m salvus_mesh_lite.interface AxiSEM --save_yaml=input.yaml
Edit it to your satisfaction and run:
$ python -m salvus_mesh_lite.interface --input_file=input.yaml
This creates and Exodus mesh file (*.e) required by the solver, AxiSEM3D.
Remember that all AxiSEM3D meshes are two-dimensional (i.e. flat) and use a one-dimensional seismic profile (i.e. there is no lateral variation in seismic parameters across the mesh) - 3D features are added in separately from the mesh.
You can visualise the meshes you create in python, but it is easier to use Paraview - which you can download for free. More on this later.
The mesher is extremely efficient, and you should be able to produce fine meshes, even on a global scale, using a laptop or desktop computer. There is therefore no need to install the mesher on your HPC architecture; rather you can just copy across the finished mesh which will be saved as an Exodus (.e) file.
The two different types of AxiSEM3D meshes#
Typing the line above should show you two available commands within the mesher which are relevant to AxiSEM3D: AxiSEM and AxiSEMCartesian. These are the two types of meshes that are compatible with AxiSEM3D: a global mesh (i.e. one that uses a curved geometry) and a cartesian one (which can have curvature on the surface, but is not designed for global-scale use). You can read the AxiSEM3D papers for more details on the differences between these meshes, but here we will focus on how to use them.