tramp.doc

实现地震射线追踪和反演的frotran程序

*** max  number  of rays  reaching  surface  exceeded ***  -  the 
    maximum allowable number  of rays reaching  the surface (not  
    including those traced in the search mode) has been reached.

*** problem with  cubic spline  *** - the  cublic spline  routine 
    was unable to  fit a  spline to  the values of  range versus  
    take-off angle, used in  determining the in-plane spreading,  
    for a particular set  of.rays. The amplitudes  of these rays  
    will be set to zero.

***  error  in  specification  of  seismogram  parameters  ***  -  
    either (1) xmins is greater than or equal to xmaxs, (2) xincs 
    is less than or  equal to zero,  or (3) the  total number of  
    seismograms is less than one or greater than pseis.

*** rec.in  is  empty  ***  -  the  file  rec.in  containing  the  
    seismogram locations is empty and isect=2.

*** too many  arrivals for seismogram  at _ km  *** - the  number 
    of arrivals  for  the seismogram  specified  exceeds parriv.  
    Only the first parriv  arrivals will be  written to the file  
    sect.out.

                          Other Programs

PLTSYN: a program  to plot synthetic  seismic sections given  the 
        source and trace locations  and the time,  amplitude and 
        phase of each arrival as output by the program TRAMP

                       Program Description
   
   Given the time, amplitude  and phase of  each arrival, PLTSYN  
plots the corresponding synthetic  seismic sections. The time  and 
distance window, reduction velocity and sample rate are specified 
by the user. The source wavelet may also be input by the user  or 
there  are  two  default  wavelets.  The  trace  spacing  may  be  
completely general. There  are three  types of amplitude  scaling 
allowed: (1)  trace normalized,  (2) distance  corrected with  an 
overall scale  factor  supplied  by  the user,  or  (3)  distance  
corrected with an  overall scale factor  determined by PLTSYN.  A 
time-saving feature  is available  whereby the  zero portions  of 
traces, common in ray synthetics, are plotted as 2-point straight 
line segments. The  time axis may  increase upwards or  downwards 
and trace shading (aka "variable area") is  also possible.  A 
constant velocity NMO correction may be applied.

                              Files

Input file: s.in contains program input parameters in  the PLTPAR 
   namelist

Input file: sect.out  is the  output file  sect.out generated  by 
   TRAMP in the following format:
(1) the  x-coordinate  (km)  of  the shot, -1 (format: F10.3, I10)
(2) the distance  (km) and  number of arrivals  for a  particular 
   trace (format: F10.3, I10)
(3) the  travel time  (s),  ampltude and  phase (radians)  of  an 
   arrival (format: 3E12.5)
Line (3) is repeated for each arrival of a  particular seismogram 
   and lines (2) and (3) are repeated for each trace of the section,
   and lines (1), (2) and (3) are repeated for each shot

Output  file:  syn.out   contains  the  constructed   seismograms  
   (format: 36(100A4))

Input file:  w.in contains  the source  wavelet.  The points  are 
   listed in  order,  each point  on  a  separate line  (format:  
   F10.3)

Output file: p.out  contains all plot  commands for the  run used  
    for input by the program RAYPLOT.

                         Input Parameters

1) Plotting parameters (PLTPAR namelist):

a) Switches  (usually 0 = off, 1 = on):

iplot - generate the plot  during the run (1), or  write all plot 
   commands to the file p.out (0), or do both (2); if iplot=-1,
   no plot is generated and no commands written to the file p.out
   (this option my be useful if iamp=1 and no plot is required)
    (default: 1)

iconv - convolve  impulse response with  source wavelet (default:  
   1)

iwavlt - source  wavlet is  a 29-point low-passed  Ricker wavelet  
   if iwavlt=0,  a single-cycle  sine  wave consisting  of nptsw  
   points if iwavlt=1, or obtained from the file w.in if iwavlt=2 
   (default: 0)

ipol -  reverses the  polarity  of the  source  wavelet (default:  
   0)

iscale -  scale  all  traces to  a  common  maximum amplitude  if  
   iscale=0, apply  a user-specifed  global  scale factor  and a  
   distant correction factor if iscale=1, or apply a global scale 
   factor determined by PLTSYN and a distance corrector factor if 
   iscale=2 (default: 0)

ishade -  equals 1 for trace shading (default: 0)

ifill -  shade  the  positive  (ifill=1)  or negative  (ifill=-1)  
   portion of the traces if ishade=1 (default: 1)

inmo -  apply a  constant RMS  velocity NMO  correction (default:  
   0)

iamp - calculate the amplitude of the seimograms at the times
   specified in the file tx.out and output to amp.out; the 
   x-coordinates of the traveltimes in tx.out must be equal to
   the x-coordinates of the seismograms (default: 0)

idump -  write the  constructed seismograms  to the  file syn.out  
   (default: 0)

b) Other plotting parameters:

vred - reducing velocity  (km/s); vred need  not be equal  to the 
   reducing velocity used  when running  TRAMP (a  zero value is  
   permitted for  no  reduction;  vred  must  be  less  than 10)  
   (default: 8)

sps - digitization rate in samples per second (default: 60)

nsmth - number of applications  of a 3-point smoothing filter  to 
    the impulse response (default: 0)

scalef -  global  scale factor  applied  to  all traces  if  iscale=1 
    (default: 100)

rcor - power of the distance correction factor if iscale=1  or 2; 
    traces will be multiplied  by their source-receiver distance  
    raised to the rcor power (default: 1)

xnorm - the  source-receiver distance  is divided  by xnorm  (km) 
    before raising to the rcor power  if iscale=1 or 2 (default:  
    100)

amp - maximum  amplitude of a  trace (km) if  iscale=0 or 2;  all 
    traces are scaled to a maximum amplitude of amp if iscale=0; 
    the scale factor scalef  is determined by  PLTSYN (and output to  
    the sreen)  so  that  the maximum  amplitude  of  the entire  
    section is amp if iscale=2; if amp  equals half of the trace 
    spacing, no overlap will occur (default: (xmax-xmin)/100)

clip - the amplitude (km) at which clipping is done  if iscale=1; 
    if clip=0, no clipping is done  (default: 0)

nptsw -  number  of  points  comprising  the  source  wavelet  if  
    iwavlt=1  (default: 19)

nskip - plot every nskip seismogram  (default: 1)

spmin - zero portions of traces that are less than spmin  (km) in 
    amplitude will be plotted as a single straight line segement 
    consisting of two points to decrease  the plot time; a value  
    of zero will  ensure that  all points  are plotted (default:  
    (xmax-xmin)/100000)

xomit - an array containing the  locations (km) of traces not  to 
    be plotted

dens -  points  per mm  for  trace shading  (default: 5)

vrms -  RMS  velocity (km/s)  used  in NMO  correction  (default: 
    2.5)

imeth - method of trace amplitude calculation if iamp=1 within a   
   window of length twin (s) following each traveltime in the file
   tx.out; if imeth=1, the average of the absoulte values of the 
   seismogram is calculated; if imeth=2, the average of the 
   maximum and minimum values of the seismogram is calculated 
   (default: 1)

twin - window length (s) following each arrival used if iamp=1
   (default: 0.25)

2) Axes parameters (AXEPAR namelist):

a) Switches  (usually 0 = off, 1 = on):

itrev - plot the  time axis with time  increasing downwards 
   (default: 0)

b) Other axes parameters:

albht - height of axes labels (mm) (default: 2.5)
 
xmin, xmax - minimum and maximum distance (km) of distance axis
xmm - length of distance axis (mm)
xtmin, xtmax - minimum and maximum values (km) of tick marks
ntickx - number of intervals separated by tick marks along distance axis
ndecix - number of digits after decimal in distance axis annotation;
   -1 for integer annotation (defaults: 0, 300, 250; values for
   xtmin, xtmax, ntickx and ndecix depend on values of xmin and xmax)

tmin, tmax - minimum and maximum time (s) of time axis
tmm - length of time axis (mm)
ttmin, ttmax - minimum and maximum values (s) of tick marks
ntickt - number of intervals separated by tick marks along time axis
ndecit - number of digits after decimal in time axis annotation;
   -1 for integer annotation (defaults: 0, 10, 125; values for
   ttmin, ttmax, ntickt and ndecit depend on values of tmin and tmax)

                         Additional Notes

User-specified source wavelet: contained in the file w.in will be 
   adjusted to have zero mean and a maximum amplitude of one.

 
External plot routines: PLTSYN is self-contained except  for the
   graphics calls inside the following CALCOMP or CALCOMP-like plot 
   routines: PLOTS, PLOT, NUMBER, SYMBOL, LINE, EMPTY, ERASE, PLOTND. 
   The file pltlib.f contains ALL these routines (and a few other 
   less important ones used by the graphics system where the 
   code was developed) and it will be necessary to replace the "call" 
   statements within each of these with their equivalents in the 
   local graphics package.

                           Array Sizes

The parameters specifying the size of all arrays within PLTSYN are 
contained in the  file pltsyn.par and  may be altered  to suit  a 
particular problem and memory requirements.

arrivals in a single seismogram - parriv

seismograms - pseis

points comprising a single trace - ppseis

points comprising the source wavelet - pwavlt

                    Warning and Error Messages

The following  is a  list and  explanation of  warning and  error 
messages generated by PLTSYN:

***  insufficient   data   in   sect.out  ***   -   a   premature  
   end-of-file has been reached  in the file  sect.out, probably 
   because the file is empty or there are  less lines containing 
   arrivals than  specified  for one  or  more  traces (see  the  
   description of the file sect.out).

*** w.in is  empty *** -  the file containing  the source  wavelt 
   is empty and iwavlt=2

*** source  wavelet is  zero  *** -  the  source wavelet  in  the 
   file w.in has zero maximum amplitude

*** max # of arrivals  exceeded on seismogram at  _ km *** -  the 
   number of arrivals on the seismogram specified exceeds parriv. 
   Edit the file sect.out to  reduce the number of  arrivals for 
   this seismogram.

*** interpolated trace for shading too long ***  - the number  of 
   points in the interpolated trace used for shading if ishade=1 
   is greater than ppseis. Decrease the value of dens.

COMBSEC: a program  to combine  two sect.out  files generated  by 
         TRAMP in two separate  runs into one  file of the  same 
         format for use by PLTSYN

                              Files

Input file: sect1.in  is the  output file  sect.out generated  by 
   TRAMP

Input file: sect2.in  is the  output file  sect.out generated  by 
   TRAMP

Output file: sect.out  contains the  combined information in  the 
   files sect1.in and  sect2.in in  the same  format for use  as 
   input to the program PLTSYN

Note: the files sect1.in and sect2.in must have been generated by 
    TRAMP using the same values of xmins, xmaxs and xincs (isect=1) 
    or the same rec.in file (isect=2).