The basic computation is for a Rayleigh wave in a half-space medium. The motion-stress vectors for this type of problem are easily computed with the BSU program halfsp. Man pages for this program can be viewed in an x-term with the command,
man halfsp
This program is very basic with only a man page for documentation. The output is a text file listing the half-space properties at the top followed by 4 columns of the motion stress vector values with depth. To read more on this topic, see Aki and Richards ((1), chapter 7). The program is run from an x-terminal with a single command:
halsfp
The user is then prompted for the half-space properties (density, P-velocity, S-velocity), and the depth sampling for the motion-stress vector computations. A typical dialog is as follows:
pm@penguin: halfsp
ENTER RHO,VP,VS
1600,800,100
ENTER FREQ,NZ,Z0,ZEND
40,50,0,20
PHASE VEL= 95.4331
This produces a file, halfsp.tmp, a portion of which is shown below:
HALFSP.F OUTPUT: RHO=0.1600E+04 MU=0.1600E+08 LAME=0.9920E+09 FREQ=0.4000E+02 P-WAVE VELOCITY=0.8000E+03 S-WAVE VELOCITY=0.1000E+03 RAYLEIGH WAVE PHASE VEL= 95.4331 R1=Horiz. Displacement R2=Vertical Displacement R3=Horiz. Stress R4=Vertical Stress DEPTH R1 R2 R3 R4 0.0 0.120E+01 -.219E+01 0.804E+02 0.000E+00 0.4 -.122E+00 -.259E+01 0.834E+08 0.458E+08 0.8 -.439E+00 -.224E+01 0.902E+08 0.495E+08 1.2 -.444E+00 -.175E+01 0.762E+08 0.418E+08 1.6 -.367E+00 -.132E+01 0.592E+08 0.325E+08 2.0 -.283E+00 -.981E+00 0.445E+08 0.244E+08 2.4 -.212E+00 -.722E+00 0.329E+08 0.181E+08 2.8 -.157E+00 -.529E+00 0.242E+08 0.133E+08 3.2 -.115E+00 -.387E+00 0.177E+08 0.972E+07 3.6 -.842E-01 -.282E+00 0.130E+08 0.711E+07 4.0 -.616E-01 -.206E+00 0.946E+07 0.519E+07 4.4 -.450E-01 -.151E+00 0.691E+07 0.379E+07 4.8 -.328E-01 -.110E+00 0.505E+07 0.277E+07 5.2 -.240E-01 -.803E-01 0.368E+07 0.202E+07 5.6 -.175E-01 -.586E-01 0.269E+07 0.148E+07 6.0 -.128E-01 -.428E-01 0.196E+07 0.108E+07 6.4 -.933E-02 -.312E-01 0.143E+07 0.786E+06 6.8 -.681E-02 -.228E-01 0.105E+07 0.574E+06 7.2 -.497E-02 -.166E-01 0.764E+06 0.419E+06 7.6 -.363E-02 -.121E-01 0.558E+06 0.306E+06 8.0 -.265E-02 -.887E-02 0.407E+06 0.223E+06 . . . 18.0 -.101E-05 -.340E-05 0.156E+03 0.855E+02 18.4 -.740E-06 -.248E-05 0.114E+03 0.624E+02 18.8 -.541E-06 -.181E-05 0.830E+02 0.456E+02 19.2 -.395E-06 -.132E-05 0.606E+02 0.333E+02 19.6 -.288E-06 -.964E-06 0.443E+02 0.243E+02 20.0 -.210E-06 -.704E-06 0.323E+02 0.177E+02
pm 2018-04-08