A simple forward computation

Before you begin

• Install Mudpy. If you've already done this then run git pull from your terminal to make sure you have the up to date latest version with the right example files.
• Configure MudPy for multiprocessor use, this can sometimes be painful and is NOT a necessary step, but try, it'll make your computations much much faster. Even your crappy laptop has at least 4 cores!

Do you have all the example files?

Look under $MUDPY/examples/forward_modeling/ you should see a listing of 6 files like so:

Ok, open the file nepal.fwd.py this is the main parameter file that you will use to command the program. This file can live anywhere in your system it doesn't really matter where.

Initialize a new project folder tree

In order to make things run smoothly and keep everything organized MudPy uses a very specific fodler structure. THis will be created for you. In the parameter file nepal.fwd.py edit the following lines:

home='/Users/dmelgar/Slip_inv/'
project_name='Nepal_forward_test'

home must already exist and is where all your MudPy projects will be stored. project_name is a name to give this particular project. This will be used to create the fodler structure. Note this is completely independent of where you are storing your .fwd.py parameter files.

Now set the action flags as follows:

init=1 
make_green=0 
make_synthetics=0 
solve=0

You are now ready to run the parameter file to create the folder structure. At your terminal run the python parameter file:

$> python $PATH_TO_FILE/nepal.fwd.py

$PATH_TO_FILE is the path where you are storing the parameter file. After s execution you should now see a new folder structure under home/project_name like so:

Prepare auxiliary files

For a forward run you will need 5 auxiliary files defining the Earth structure model, the fault geometry, the kinematic rupture, and the station locations and kinds of data you want to synthesize. Note that these files need to be in very specific locations where MudPy will look for them.

1. Earth structure: Copy the file avouac.mod from the examples folder to home/project_name/structure/ the file should look like so:

The first column is the layer thickness in km, the second column is vs in km/s, the third column is vp in km/s, the fourth column is density in g/cm^3, the fifth column is Qs and the last column is Qp.

2. Station locations file: Copy the file nepal.sta to home/project_name/data/station_info/. This file is simply the coordinates of the sites you are interested in synthesizing. For this example these are the locations of high rate GPS stations.

3. Station gflist file: Copy the file gps.gflist' to home/project_name/data/station_info/`. THis file controls what types of data re synthesized, displacement (GPS), velocity (strong motion), InSAR, etc. You need to modify the paths to point to your specific project folder, right now it looks like this and points to the project folder on my system: