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这是一个TOMO TO GMT的源码

 SHAREWARE TOMO2GMT:    Preparation (interactively) of main output from
                        SIMULPS (versions 13Q and 14) and FATOMO for sub-
                        sequent plotting with GMT. At the end of this 
                        README you will find a brief outline explaining 
                        how to create tomographic images using TOMO2GMT
                        and GMT.
 			
 
 
    src_code	       : source code and Makefile of tomo2gmt code
    GMT		       : GMT shellscripts to plot output of tomo2gmt
    example_tomores    : example for plotting tomography results (FATOMO)
    example_raydens    : example for plotting ray density tensor
    ray_dens.eps       : principle of ray density tensor display (ps-file)
    
 	
 Compile the source code using the Makefile in the 'src_code' directory. 
 Create a GMT directory and copy the executable of TOMO2GMT and the main
 print output file of SIMULPS or FATOMO (must be called "output") to the
 GMT directory. Create a GMT/VP  subdirectory.
 
 The main purpose of TOMO2GMT is to analyze the output by SIMULPS/FATOMO 
 and to prepare it in a fashion so that the results can be easily plotted 
 by GMT. To avoid any additional interpolation by GMT, the results are 
 already regridded by TOMO2GMT on an equally spaced grid using a user 
 defined gridspacing (in x,y,z). Either a nearest-neighbor or a linear 
 interpolation can be chosen. 
 
 (CAUTION: If your model has been rotated in SIMULPS, the output of 
 TOMO2GMT is no longer equally spaced. In such a case, use a gridding 
 routine by GMT (f.e. nearest-neigbor interpolation) to create an equally 
 spaced grid.)
 
 TOMO2GMT reads the main output file (must be named 'output') by SIMULPS 
 (versions 13Q and 14) or FATOMO and extracts the results for
 		
 		- horizontal depth slices,
 		- vertical depth sections along profiles of constant lati-
 		  tude or longitude,
 		- and vertical depth sections along user defined profiles.
 		
 The extracted values regard resolution estimates (HIT, DWS, RDE, spread), 
 lateral variations of velocity (in % and as absolute velocity), and final 
 velocity model parameters. For each section, TOMO2GMT creates an output
 file in the subdirectory 'VP' for further use with GMT. Velocities (VP & 
 Vp/Vs) and velocity differences are interpolated from the grid they are 
 defined in the tomographic application (called seismic grid) onto a user
 defined finer grid. Interpolation can be done either by trilinear inter-
 polation or by nearest neighbour interpolation. Resolution estimates, how-
 ever, are not interpolated. 
 Horizontal depth sections can be computed for each original layer of the 
 tomographic inversion or at newly user defined depths. In the latter case,
 the values are being interpolated! Vertical depth sections along profiles 
 of constant latitude or longitude are grouped around the origin of short 
 distance conversion, which requires an odd number of such depth sections 
 (the middle one corresponds to that profile running through the origin). 
 Spacing of the sections (in degrees) will be defined by the user. Vertical 
 depth sections along user defined profiles may start at any point within 
 the model. The grid spacing along the profile is given by the user. There-
 fore, the end point of the profile might be adjusted by TOMO2GMT to fit 
 the desired grid spacing.
 
 GMT shell scripts:
 Included in the TOMO2GMT package are GMT shellscripts to plot resolution 
 estimates in horizontal depth sections and vertical depth sections (either
 along constant latitude/longitude or along user defined profiles), per-
 centage velcity changes in horizontal depth sections, and absolute velo-
 cites along user defined profiles. See examples in the directory 
 'example_tomores'. (GMT shell scripts to plot the ray density tensors in 
 horizontal planes or in latitude depth sections are included in the 
 directory 'example_raydens'.) Note that some variables in these shell
 scripts must be changed to your requirements!
 Postscript files obtained by the GMT shellscripts can be found in the 
 example directories. NOTE: all GMT scripts have been set up for GMT3.3.1 
 and measure unit in INCHes! The .gmtdefaults file used can be found in 
 the GMT directory.
 

 Special option:  Creating a file "fixnodes.dat" for usage as input "MOD" 
  (TOMO2GMT)      file for future runs by SIMULPS or FATOMO
                  
                  
                  The file 'fixnodes.dat' which contains all the grid 
                  nodes which have a DWS less than the specified threshold 
                  (in the CNTL file). The grid nodes are printed in the 
                  file 'fixnodes.dat' in a format which may directly be 
                  used in the "MOD" file to fix grid nodes a priori. So, 
                  to get around with the annoying typing of a priori fixed 
                  grid nodes in the MOD file, choose a DWS cut off value, 
                  perform one single iteration of the inversion, run TOMO-
                  2GMT, and use the file 'fixnodes.dat' to a priori fix 
                  your grid nodes in the MOD file.    
 
  
 Special option:  Display of Ray Density Tensors (RDT) 
  (TOMO2GMT)     
                  
                  TOMO2GMT has been set up to display the ray density 
                  tensor (E. Kissling, Geotomography with Local Earthquake 
                  Data, Rev. Geophys., 26, 659-698,1988) as computed by 
                  TOMEK (E. Kissling; [e-mail]). This 
                  option  requires two output files 'raydens.out' and 
                  'resol_main.out' of TOMEK. Based on the ray illumina-
                  tion resembled by the ray density tensor and the total 
                  weighted ray length within an inversion cell, 4 quality 
                  classes are constructed. Furthermore, the projection of 
                  the main ray directions onto the corresponding plane 
                  (xy,xz,yz) are computed and later displayed (S. Husen, 
                  E.Kissling, E. Flueh; Shalheveth Freier International 
                  Workshop on Advanced Methods in Seismic Analysis: High 
                  Precision Hypocenter Location and Seismic Tomography, 
                  Dead Sea, Israel, 1998; also see attached ps-file).
 
 
 Comments to interactive session with TOMO2GMT:
 
 Once you started TOMO2GMT, you are bothered with some questions. In some 
 cases default answers are given in brackets; hit return to choose them:
 
 1) which output is read in SIMULPS or FATOMO (s/f) or none (n)?
     The latter option has been included to plot only ray density tensors, 
     which does not require output by SIMULPS or FATOMO.
     
 2) what kind of interpolation for velocities?
     Linear interpolation should be used with SIMULPS13Q since the grid 
     consists of grid nodes with linear interpolation. Absolute velocities 
     computed by FATOMO should be also plotted with linear interpolation, 
     whereas pertubations (% and abs.) should be plotted with nearest 
     neighbour since they are computed for inversion cells.
     
 3,4) enter desired grid spacing ....
       Desired grid spacing in x,y and depth (for vertical depth sections)
       used for regridding. For SIMULPS13Q grid spacing must be in 
       bld-units (either 1 km or 0.1 km; see your CNTL input file for 
       details), for FATOMO in km.
       
 5,6,7,8) Do you want to create...
 	self explaining
 	
 9) Changes (abs. and %) of model parameters can be calculated relative to ..
     In general model changes should be computed relative to the initial 
     reference velocity model (i.e. minimum 1D model). However, under some
     circumstances you might want to calculate model changes relative to 
     the 2D/3D initial model (f.e changes between subsequent 3D inversions),
     to a 1D model of average (final) layer velocities, or an external 1D 
     model. The latter options requires an additional input ascii-file 
     listing the velocities for each layer on a separate line.
     
 10) Do you want to calculate SPREAD VALUES [n]?
      Spread values may be computed based on the formula by Michelini & 
      McEvilly (BSSA, 81, 524-552, 1991). This option requires the full 
      resolution matrix printed in the file 'resol.out'. In the case of 
      SIMULPS13Q the file 'nodes.out' is also required.
      
 11) 1D-model of absolute velocities ..... [n] ?
       A local 1D model of velocities at a given lat/lon position may be 
       useful when comparing tomographic results with those of other seismic 
       studies.
       
 12) Do you want a normalisation of KHIT/DWS ... [n] ?
       self explaining
       
 13) Do you want to plot ray density tensors [n] ?  Default: No
       This option requires prior run of TOMEK (see remarks on ray density
       tensor at the beginning of this README).
       
 some more questions appear later:
 
 14) only for SIMULPS output
      do you want to include (fixed) boundary nodes [n] ?
        SIMULPS requires planes of nodes around all sides of the model 
        placed several hundred km away. These nodes are fixed during the 
        inversion. When you have stations and earthquakes which are between
        these boundary nodes and the next nodes of your model, you might 
        want to include the boundary nodes when displaying the results.
 
 15,16) only for SIMULPS output
      (SIMULPS does not output layers with no hits...)
      if your output does not start with the first layer....
      	Layers which are not hit by any ray are not printed in the output 
      	file. Therefore, you need to specify the highest and probably the
      	lowest layer number in your output.
	
 17) only for horizontal depth sections
      Do you want to plot horizontal depth sections at the predefined
      seismic grid [y]?
        In general, results are displayed for those layers defined in the 
        model. Sometimes, if you want to compare results obtained on diffe-
        rent grids at depth, you need to define new layers so that results 
        can be compared at the same depth. Be aware, that in this case 
        values are interpolated.
       
 18) Do you want to plot just a part of the model ...[n]?
 	With this option you can zoom into your model and just print out 
 	values of a part of the model. For example, in a depth section you 
 	want to skip the upper layers, since they are not well resolved. 
	
	
--------------------------------------------------------------------------

  BRIEF OUTLINE HOW TO GET COLORED IMAGES USING TOMO2GMT & GMT(3.3.1)
	
 general remarks on displaying tomographic results:
   Normally, one wants to plot the results the way they were calculated 
   during the inversion. This means, that absolute velocities should be 
   plotted with linear interpolation, since they are defined on grid nodes 
   with linear interpolation for SIMULPS and FATOMO. Resolution estimates 
   (such as KHIT, DWS, RDE) should be plotted with nearest neighbor inter-
   polation, which is done by default in TOMO2GMT. Velocity model changes 
   in percentage usually are only displayed in horizontal cross sections,
   while in vertical cross sections absolute velocities are preferable.   
	
1) create directory GMT (preferable under your home directory) and copy 
   content of the GMT-directory of the TOMO2GMT-package into this directory; 
   be sure to copy also the .gmtdefaults file! otherwise create a new 
   .gmtdefaults using the gmtdefaults command of GMT change "measure unit" 
   to inch.
    
2) change to the directory which contains your output files of SIMULPS/
   FATOMO and create subdirectory VP
   
3) run TOMO2GMT in the same directory which contains your output files 
   of SIMULPS or FATOMO 
    
4) now you should find some output files (f.e. planeXXXX.X.xyz) of 
   Tomo2GMT in the VP directory
    
5) change to the GMT directory you created in 1)

6) convert gridspacing in xy you used in TOMO2GMT [in km] to degrees. 
   Since GMT is very sensitive to the grid spacing values, the best way to 
   do this is to use the minimum and maximum longitude/latitude values, 
   divide the difference by the corresponding distance in km and multiply 
   it by the grid spacing used in TOMO2GMT. Be sure to use at least 8 
   digits!!

7) modify the GMT shellscript you wish to use (f.e. plane_percvp.gmt to 
   plot percentage velocity change in horizontal depth sections):
    - set Istring to the values computed under 6)
    - set wpath to the GMT directory created under 1)
    - set inpath to the directory containing the output files of tomo2mgt
    - set Rstring to your boundary values
    - set tomo to simul if you used SIMULPS or fatomo if FATOMO
    - set values between the parentheses in the foreach statement to the 
      planes you want to plot
    
8) run shellscript 
  
     
 
 please send any comments to
 
 	Stephan Husen				Florian Haslinger
 	  Institute of Geophysics	          UW Madison
 	  ETH-Hoenggerberg			  Dept. of Geology & Geophysics
 	  8093 Zurich				  1215 W Dayton St.
 	  Switzerland				  53706 Madison WI
 	  					  USA
 	  					  
     phone: [phone]			    [phone]
     fax:   [phone]			    [phone]
     email: [e-mail]	    [e-mail]