readme

seismic software,very useful

psgraph takes different data formats.  See README.graph.  11/20/90 

psmerge is the general tool hinted at in earlier READMEs;
pswig2p and pswig2b have consequently been wiped.
Not extensively tested.  11/11/90

psmovie and pscube were added by Zhiming Li just before leaving
for Western, so not thoroughly checked out.  10/03/90