Creating a mesh parameters in GravMag inversion

[alexeytsv]

In Gravity and Magnetic 3D Inversion application (v0.9.0-rc.3) there are no parameters for creating a mesh (Mesh option in Inversion Parameters)

[github-actions]

JIRA issue [GEOPY-687] was created.

[domfournier]

Hi @alexeytsv ,
That is correct, we have removed the mesh creation within the inversion applications themselves. You will need to run the octree mesh creation application as pre-processing step.

It was voted out by our users. The reason being that it made the ui more complicated and was prone of launching long inversions with a bad mesh. It forces the users to think about an optimal discretization ahead of running the inversion.

Sorry about that.

[alexeytsv]

Thank you for the information.
However, there are a few questions about OctreeMesh Creation:

1. Why the application does not recognize 2D grid types in geoh5 (I've imported topo grid in GA)?
2. Why the mesh saved in new geoh5 (I need to write script to copy the mesh into original file)?

[domfournier]

1- Hmm good point about the 2d grid. We just need to add it to the list of accepted objects. That being said, data from a 2d grids don't really have a z position (just flat constant) you might have to also create yourself a points from cell centers with drape Z?

2- No you should just be able to ctrl-c the mesh in GA, then ctrl-v in your other project. Or second option you just drag and drop the geoh5 that has the mesh to your viewport. GA is pretty cool that way.

[alexeytsv]

1. Creation points from 2d grid cells available only in Pro license.

[domfournier]

Fair enough. Here's a workaround that should work (untested)

• Use the export app to create a csv from your 2d grid. This csv will load as Points by default in GA.

• Use the data transfer app to interpolate your elevation from dem or topo surface.

• Use the calculator app to assign elevation to your points.

From there you will have points and topo to create your octree. Should work...

Dom

[domfournier]

Would probably be a good idea to make an app for that - 2d grid to draped points. We could then simplify the inversion app even more and let you do the conversion prior as well.

[domfournier]

Will add the option in the jupyter-app Octree mesh creation only to help out free users on GEOPY-687 for v0.9.1