What's in these Notes?

These notes are a brief guide to using the computer programs that are available for moment-tensor inversion. The programs use SAC file format, so much of the notes, particularly the preparation of the observations is easily done using SAC and SAC macros. Most of these codes were written by Chuck Ammon and George Randall. (As you browse through the codes, you will see routines and functions that have an even longer history).

Here's an outline of this little moment-tensor inversion web (computer program names are in red):

  • Data Preparation (SAC)
  • Green's Functions Preparation (e.g. SAC, marktime, etc.)
  • Moment-tensor inversion
    • Deviatoric Moment Tensor:
      • Least-squares: mtinv
      • L1-norm minimization: l1mtinv
    • Full moment-tensor
      • Least-squares: mijinv
    • Double-Couple Grid Search
      • srcgrd

The links at the bottom of this page (and subsequent pages) can be used to steer through this site. Send me a note if you find these pages useful or if you find errors. I can't invest much energy in this site, but will try to fix glaring mistakes or muddled explanations.

Where Do I Get The Computer Programs? HERE

Overview | Seismogram Prep | "Green's Functions" | Input File Format
Program Output | References | Back to Ammon's Home

Prepared by: Charles J. Ammon

Made on a Mac