How can can generate 2-D model containning complex shape abnormal

if i want to generate some model just like this,how to do this?

I would recommend looking into gempy. They have examples easy to follow in there. If you can get through this one intro example you should be good to go.

I tried last weekend and the connection to simpeg is really straight forward. Just need a simple re-ordering of the indices, which I can provide to you once you get there.