SYNOPSIS

PERL PROGRAM NAME:

AUTHOR

DATE:

DESCRIPTION:

Version:

USE

NOTES

Examples

SYNOPSIS

SEISMIC UNIX NOTES GBBEAM - Gaussian beam synthetic seismograms for a sloth model

gbbeam <rayends >syntraces xg= zg= [optional parameters]		



Required Parameters:							

xg=              x coordinates of receiver surface			

zg=              z coordinates of receiver surface			



Optional Parameters:							

ng=101           number of receivers (uniform distributed along surface)

krecord=1        integer index of receiver surface (see notes below)	

ang=0.0          array of angles corresponding to amplitudes in amp	

amp=1.0          array of amplitudes corresponding to angles in ang	

bw=0             beamwidth at peak frequency				

nt=251           number of time samples				

dt=0.004         time sampling interval				

ft=0.0           first time sample					

reftrans=0       =1 complex refl/transm. coefficients considered	

prim             =1, only single-reflected rays are considered	",     

                 =0, only direct hits are considered			

atten=0          =1 add noncausal attenuation				

                 =2 add causal attenuation				

lscale=          if defined restricts range of extrapolation		

aperture=        maximum angle of receiver aperture			

fpeak=0.1/dt     peak frequency of ricker wavelet			

infofile         ASCII-file to store useful information		

NOTES:								

Only rays that terminate with index krecord will contribute to the	

synthetic seismograms at the receiver (xg,zg) locations.  The		

receiver locations are determined by cubic spline interpolation	

of the specified (xg,zg) coordinates.					

AUTHOR: Juan Lorenzo (Perl module only)

 MODIFIED:  Andreas Rueger, Colorado School of Mines, 08/18/93

	Modifications include: 2.5-D amplitudes, computation of reflection/

			transmission losses, attenuation,

			timewindow, lscale, aperture, beam width, etc.

User's notes (Juan Lorenzo) untested

CHANGES and their DATES

Import packages

instantiation of packages

Encapsulated hash of private variables

sub Step

collects switches and assembles bash instructions by adding the program name

sub note

collects switches and assembles bash instructions by adding the program name

sub clear

sub amp

sub ang

sub aperture

sub atten

sub bw

sub dt

sub fpeak

sub ft

sub krecord

sub lscale

sub ng

sub nt

sub prim

sub reftrans

sub xg

sub zg

sub get_max_index

max index = number of input variables -1