Acoustic Media 1- two welded halfspaces

Introduction

The purpose of this problem is to make some wholespace synthetic seismograms

1. Read the manual that is located on crust.eas.slu.edu at /home/rbh/PROGRAMS.330/DOC/OVERVIEW.pdf/cps330.pdf, e.g.,

acroread /home/rbh/PROGRAMS.330/DOC/OVERVIEW.pdf/cps330.pdf

2. Using the program mkmod96 to create the following velocity model (NOTE give this the name 2half.mod):

    H Vp Vs Density Qp Qs Etap Etas FrefP FrefS
    -4 1 0 1.0 0 0 0 0 1 1
    2 2 0 1.5 0 0 0 0 1 1

3. Plot the model using shwmod96

4. Create a distance file, which you will name dfile, with entries "Distance DT NPTS T0 VRED" for the distances used for figure 3.2.2 in the text, e.g., you will require entries such as
    1.2 0.05 256 0.0 0.0
    1.6 0.05 256 0.0 0.0
   ......
   6.8 0.05 256 0.0 0.0

5. Use the program hprep96 to generate the ray paths between the source and receiver:
     hprep96 -M 2half.mod -HS -1.0 -HR -1.5 -ALL -TH -BH -d dfile

6. Then run the program hwhole96

     hwhole96

      and convolve with the source time function

     hpulse96 -V -p -l 4 > file96

     and them plot the figure using fprof96

     fprof96 -S 2.0 < file96

     You can view the plot with the following commands:

     plotxvig < FPROF96.PLT

     or you can get a PostScript file that you can plot using the command

     plotnps -F7 -W10 -K < FPROF96.PLT > my.ps

Of course you can also look at the traces using gsac by creating the SAC waveform files using the command f96tosac -B < file96

7. The plots that will be created will be the vertical and radial component of the particle velocity, and since this is a fluid problem, you will also see the pressure field in the fluid.

Questions

What is the difference between the shape of the velocity and pressure synthetic time histories?
How dows amplitude change with distance>