FORWARD MODELING CODES

I. Traveltime Modeling Codes

1. Ray Tracing for 2-D and 3-D Media

Author: Yonghe Sun (1991)

Tracing transmission rays in 2-D and 3-D slowness media.

"README" = readme file;

"ray3.f" = ray tracing code; "rays.f" = subroutine code;

"params.inc" = include file; "ray3m.inf" = document file;

"demo.1d" = 1-D input & output demo; "demo.3d" = 3-D input & output demo.

2. Traveltime Calculation in a 2-D TI Medium by Huygens' Principle

Author: Fuhao Qin (1992)

Traveltime calculation for quasi-P, quasi-SV and SH waves in a (2-D) TI medium by Huygens' principle.

"README" = readme file;

"aneik.f" = traveltime computing code; "anmod.f" =model builder;

"aneik.in" ; "anmod.in" = input files.

3. Finite-Difference Solution to the 2-D Eikonal Equation

Author: Fuhao Qin (1992)

First arrival traveltime calculation for 2-D isotropic media.

"README" = readme file;

"eik.f" = traveltime computing code; "ineik" = input file;

"mod.f" = model builder; "inmod" = input to mod.f.

4. Finite-Difference Solution to the 3-D Eikonal Equation: Version 1.0

Authors: Wenying Cai and Fuhao Qin (1991)

Computing traveltimes in 3-D isotropic media by a finite-defference solution to the 3-D eikonal equation.

"README" = readme file;

"eik3d.f" = traveltime computing code; "eik3d.in" = input file;

"mod3d.f" = model builder;

5. Finite-Difference Solution to the 3-D Eikonal Equation: Version 1.1

Updated by Jianming Sheng, Min Zhou and Chaiwoot Boonyasiriwat (2006)

Computing traveltimes in 3-D isotropic media by a finite-defference solution to the 3-D eikonal equation.

"README" = readme file;

"main.f" = the main program;

"front3d.f" = 3D Eikonal solver subroutines;

"model_param.h" = Model parameter file;

"Makefile" = GNU Makefile for this package;

"viewtime.m" = Matlab script for viewing the traveltime file;

"time.png" =Image of the 3D traveltime produced by Matlab;

6. Shortest path Matlab codes

Author: Ruiqing He (2002)

Computing first arrival traveltime.

"Mray.m" = Matlab source code;

II. Wavefield Modeling Codes

1. Finite-Difference Solution to the 2-D Acoustic Wave Equation

Authors: Jerry Schuster (1989) and Jinlong Xu

Modeling of 2-D borehole acoustic synthetic seismograms by a 2-4 finite-difference solution to the 2-D acoustic wave equation. The accuracy is 2nd-order in time and 4th-order in space, and code can handle irregular free-surfaces.

"README" = readme file;

"pp4.f" = modeling code; "indat" = input file;

"mod.f" = model builder; "inmod" = input to mod.f;

"README.CONVERT" = readme file for convert code;

"doconvert" = execution file to call convert code;

"ftsu.f" = convert code which can be used to conver Fortran unformatted data to SU format data or reverse;

"segy.com" = include file for convert code;

"ftr.dat.in" = input file for convert code, contains trace number and sample interval;

"pre1" ;"prel2";"pre3" = output seismograms of PP4.F.

2. Finite-Difference Solution to the Axisymmetric Acoustic Wave Equation

Author: Jinlong Xu (1993)

Modeling of axisymmetric borehole acoustic synthetic seismograms by a 2-4 finite-difference solution to the axisymmetric acoustic wave equation. The accuracy is 2nd-order in time and 4th-order in space.

"README" = readme file;

"pp425.f" = modeling code; "indat" = input file;

"mod.f" = model builder; "inmod" = input to mod.f.

"pp425.par" = include file.

3. Finite-Difference Solution to the 3-D Acoustic Wave Equation

Author: Kim Bak Olsen (1992)

Modeling of 3-D acoustic synthetic seismograms by 2-4 finite-difference solution to the 3-D acoustic wave equation. The accuracy is 2nd-order in time and 4th-order in space.

"README" = readme file;

"fd3dac.f" = modeling code; "hom3d.f" = earth model builder;

"table" ; "in3dac" = input files;

"parstat" ; "bush" ; "field" ; "earth" = include files.

4. Finite-Difference Solution to the 2-D P-SV Wave Equation

Authors: Yi Luo, Jerry Schuster (1989) and Jinlong Xu

Modeling of 2-D P-SV synthetic seismograms by a 2-4 finite-difference solution to the 2-D elastic wave equation. The accuracy is 2nd-order in time and 4th-order in space.

"README" = readme file;

"psvr4.f" = modeling code; "indat" = input file;

"mod.f" = model builder; "inmod" = input to mod.f.

"psvr4.par" = include file.

5. Finite-Difference Solution to the 2-D SH wave Equation

Author: Jinlong Xu (1992)

Modeling of 2-D SH elastic synthetic seismograms by a 2-4 finite-difference solution to the 2-D SH elastic wave equation. The accuracy of the code is 2nd-order in time and 4th-order in space. This program can also model the SH response of free-surfaces with irregular geometry.

"README" = readme file;

"sh4.f" = modeling code; "indat" = input file;

"mod.f" = model builder; "inmod" = input to mod.f.

"sh4.par" = include file.

6. Finite-Difference Solution to the 2-D TI Elastic Wave Equation

Author: Fuhao Qin (1992)

Modeling of TI elastic synthetic seismograms by a 2-4 finite-difference solution to the 2-D TI elastic wave equation. The accuracy is 2nd-order in time and 4th-order in space.

"README" = readme file;

"an2dh.f" = modeling code(Z); "an2dv.f" = modeling code(X);

"indat" = input file; "anmod1n.f" = model builder;

"inmod" = input to mod.f.

7. Finite-Difference Solution to the 3-D Elastic Wave Equation (Cray)

Author: Kim Bak Olsen (1991)

Modeling of 3-D synthetic seismograms by a 2-4 finite-difference solution to the 3-D elastic wave equation, optimized for CRAY supercomputers with a Solid State Device (SSD). The accuracy is 2nd-order in time and 4th-order in space.

"README" = readme file;

"fd3d2.f" = modeling code; "hom3d.f" = model builder;

"table" ; "in3d" = input files;

"disstat" ; "iadstat" ; ; "parstat" = include files.

"crossdmx.f" ; "surfdmx.f" = demultiplexing code.

8. Finite-Difference Solution to the 3-D Elastic Wave Equation (IBM)

Author: Kim Bak Olsen (1991)

Modeling of 3-D synthetic seismograms by a 2-4 finite-difference solution to the 3-D elastic wave equation, optimized for multi processor IBM3090 supercomputers with Extended Memory and is set up for an MVS enviroment. The accuracy is 2nd-order in time and 4th-order in space.

"README" = readme file;

"table' ; "in3d" = input files;

Files for compilation, linking, and model creation "fort.tar"; "cntl.tar"; "clist.tar";

Include Files "copy.tar".

9. Separation of 2-D P-Waves and S-Waves

Author: Kim Bak Olsen (1991)

Separation of a 2-D elastic wavefield into P-energy and S-energy.

"README" = readme file;

"sep.f" =separation code.

10. Finite-Difference Solution to the 2-D P-SV Wave Equation Using An Adaptive Grid

Author: Xu Ji (1994)

Modeling of 2-D P-SV synthetic seismograms by a 2-4 finite-difference solution to the 2-D elastic wave equation using the adaptive grid method. The accuracy is 2nd-order in time and 4th-order in space.

"README" = readme file;

"vgpsvr4.f" = modeling code; "vindat" = input files;

"mod.f" = model builder; "model" = input to mod.f;

"vgpsvr4.inc" = include file.

11.Finite-Difference Solution to the 2-D Acoustic Wave Equation Using An Adaptive Grid

Author: Yue Wang (1996)

Modeling of 2-D acoustic pressure synthetic seismograms by a 2-4 adaptive staggered grid solving finite-difference solution to the 2-D acoustic wave equation. The accuracy is 2nd-order in time and 4th-order in space.

"README" = readme file;

"ap4.f" = modeling code; "indat" = input file;

"mod.f" = model builder; "ap4.inc" = include file.

12. Finite-Difference Solution to the Axisymmetric Viscoelastic Wave Equation

Author: Yue Wang (1995)

Modeling of axisymmetric viscoelastic synthetic seismograms by a 2-4 staggered grid finite-difference method. The accuracy is 2nd-order in time and 4th-order in space.

"README" = readme file;

"ve2d5.f" = modeling code; "indat" = input file;

"mod.f" = model builder; "ve2d5.inc" ; "segy.h" = include files.

13. Finite-Difference Solution to the 2-D P-SV Wave Equation Using An Adaptive Grid with Conservation Flux Condition

Author: Yue Wang (1996)

Modeling of 2-D P-SV synthetic seismograms by a 2-4 finite-difference solution to the 2-D elastic wave equation using the adaptive grid method with conservation flux condition. The accuracy is 2nd-order in time and 4th-order in space.

"README" = readme file;

"ae2d.f" = modeling code; "indat" =input file;

"mod.f" = model builder; "ae2d.inc" = include file.

III. Electromagnetic Finite-Difference Modeling

Finite-Difference Solution to the 2-D Maxwell's Equation

Author: Jerry Schuster and Wenying Cai (1990)

Modeling of 2-D synthetic electrograms by a 2-4 staggered finite-difference solution to the 2-D Maxwell's equation. The accuracy is 2nd-order in time and 4th-order in space.

"em2d.f" = modeling code; "mod.f" = model builder;

"indat" = input file; "inmod" = input to mod.f.