This is a discussion of the use of the program hudson96 which was created from pieces of hrftn96, hspec96p, and time96 in March, 2008.

The program on the direct teleseismic P or S arrival through the use of a stationary phase approximation for the ray parameter connecting the direct arrival from the source to the receiver. The interesting feature of this approach is the use of propagator matrices for the source and receiver crusts, so that the depth phases are automatically included as well as the details of the source and receiver crustal models.  The program is self contained in that the travel time, T* and geometrical spreading are computed within the program.  A tutorial on the use of the program is on the tutorial page.

Hudson, J. A. (1969). A quantitative evaluation of seismic signals at teleseismic distances - II. Body waves and surface waves from an extended source, Geophys. J. Roy. astr. Soc. 18, 353-370.


The syntax of the program is given by the command hudson96 -h :

 USAGE: hudson96 [-TEL modeltel] [-SRC modelsrc] [-REC modlrec]  [ -HS hs ] [ -O offset ] [-P] [-S]  [-GCARC gcarc] [-DT dt] [-NPTS npts]  [-NOSRC] [-NOREC] [-NOTEL] [-?] [-h]
 -TEL modeltel (default none) Earth velocity model
 -SRC modelsrc (default modeltel) Velocity model for source
 -REC modelrec (default modeltel) Velocity model for receiver
 -HS hs        (default 10 km) Source depth
 -GCARC gcarc  (default 30 degrees) Arc distance
 -NPTS npts    (default 1024) Number of points in time series
 -DT dt        (default 0.05 sec) Sampling interval
 -O  offset    (default 10.0 sec) Time offset before signal
                    wrap-around, but output only npts
 -P            (default true)  make P synthetic
 -S            (default false)  make S synthetic
 -NOSRC        (default false) Turn off source input
 -NOREC        (default false) Turn off receiver part
 -NOTEL        (default false) Turn off teleseism  geometrical
                      spreading and attenuation
 -?            Display this usage message
 -h            Display this usage message
 The program creates the file hspec96.grn for hpulse96.
 The program creates the files hudsonsrc.mod and hudsonrec.mod,
 which are the complete models (model96 format) used for the src and rec regions from the surface to interior.
 these can be plotted using shwmod96.

This program creates a file hspec96.grn which is used by hpulse96 to create a file96 time series file.

Test Runs

The tar-ball containing the scripts for the test runs is  hudson.tgz