Forward_image seismic wave is not good

Hi everyone,
What’s wrong with it.The source can not propagate and the frequency dispersion is serious.


So what can I do?I try to reduce the DT size,but an error occur as follow.
Program received signal SIGFPE: Floating-point exception - erroneous arithmetic operation.

Backtrace for this error:

#0 0x7f8f886fdc2d in ???

#1 0x7f8f886fce45 in ???

#2 0x7f8f883cef5f in ???

#3 0x55785ceb0c2a in compute_forces_viscoelastic_

at src/specfem2D/compute_forces_viscoelastic.F90:570

#4 0x55785ceb2fe8 in compute_forces_viscoelastic_main_

at src/specfem2D/compute_forces_viscoelastic_calling_routine.F90:63

#5 0x55785cefa6f1 in iterate_time_

at src/specfem2D/iterate_time.F90:165

#6 0x55785ce667d6 in specfem2d

at src/specfem2D/specfem2D.F90:381

#7 0x55785ce667d6 in main

at src/specfem2D/specfem2D.F90:349

===================================================================================

= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES

= PID 10985 RUNNING AT doughnut

= EXIT CODE: 8

= CLEANING UP REMAINING PROCESSES

= YOU CAN IGNORE THE BELOW CLEANUP MESSAGES

===================================================================================

YOUR APPLICATION TERMINATED WITH THE EXIT STRING: Floating point exception (signal 8)

This typically refers to a problem with your application.

Please see the FAQ page for debugging suggestion.

Please help me who are familiar with it.Thanks.

Hi brioglade,

I ran into the same error as you got. I think the issue is with DT. It needs to be equal or smaller to the recommended DT from running the solver (xspecfem2D).

First I ran the meshing tool (xmeshfem2D). After that I ran xspecfem2D until the time stepping begins. If you look at the output, it gives us the recommended DT. Try using that DT in the Par_file.

I am not sure whether this is the right thing to do. But at least it is working for me. I am not an expert in this so, I might be wrong.

Good luck.

Cheers,
Pasan

Dear Pasan,
Thank you for your reply.

  1. The same elastic force source and some other same type in gmsh or cubit mesh simulation are different from what I simulate in the building_in mesh.

  2. No matter what I modify the file,can not see the time delay of S wave (behind P wave) still.

Best Regards,

Tang

Pasan Herath via Computational Infrastructure for Geodynamics geodynamics@discoursemail.com 于2019年10月18日周五 下午5:06写道:

Hello Tang,

Are you using a source that could generate shear waves?

Cheers,
Pasan

Hi Pasansherath,
Yes,I think that the right simulation should generate shear waves naturally.
Now,I found that .jpg format image can not show the shear waves and the .ps format image can show it.Why?
Which parameter should I modify that I can not see solver_output.txt file?
I could not find the difference of the par_files that the solver_output.txt file does exist in other simulation.
Thank you.
Cheers,
Tang