Model with a lenticular inclusion (LEN)
- Transforming surfaces and velocity sections into VRML or GOCAD. Computing 3-D P-wave velocity cube (GOCAD Voxet). len-mod.h
- Generating colour PostScript files with the velocity sections across the model. len-grd.h
- Generating 3-D grids of values of velocity and of indices of complex blocks. len-grid.h
- Performing initial-value ray tracing of rays shot in a single vertical plane from the point source. len-crti.h
- Performing 3-D two-point ray tracing for a point source. Adding source, receivers and two-point rays into VRML or GOCAD representation of the model with surfaces. len-crt.h
- Transforming wavefronts and two-point rays into VRML. len-wf.h
- 3-D two-point ray tracing for the plane wave incident at the bottom of the model. lenb-crt.h
- 3-D two-point ray tracing for exploding reflector (zero-offset rays). lenz-crt.h
- Controlled initial-value ray tracing in the model followed by 3-D interpolation of travel times within ray cells. leni-mtt.h
- Initial-value ray tracing of the cone of rays in the model followed by calculation of the derivatives of the travel times with respect to the model B-spline coefficients. Adding source, receivers and rays into VRML or GOCAD representation of the model with surfaces. len-cone.h
- Performing shortest path calculation of the first arrival travel times and the corresponding rays on a rectangular grid in the model (network ray tracing). len-net.h
- Simple demonstration history file used to debug and test the inversion programs. The data to be inverted are created by discretization of model LEN. The same model is then obtained by the overdetermined least-square inversion. len-inv.h
Preliminary Reference Earth Model (PREM)
- Generating PostScript files with the sections across the model PREM displaying the velocities and indices of complex blocks. prem-grd.h
- Transforming surfaces and a velocity section into VRML or GOCAD. prem-mod.h
- Tracing pPKP+pPKiKP, pPKIKP, PKP+PKiKP and PKIKP rays in spherical coordinates. prem-crt.h
- Dziewonski, A.M. & Anderson, D.L. (1981): Preliminary reference Earth model. Phys. Earth planet. Inter., 25, 297.
Model with homogeneous layers (ELF1, MI)
- Transforming model with homogeneous layers separated by plane interfaces (ELF1) into VRML or GOCAD. elf1-mod.h
- Performing 3-D two-point ray tracing for moving source and receiver profile. elf1a.pl, elf1b.pl, elf1c.pl
Salt dome model (SD1)
and dislocated salt dome model (SD2)
- Transforming salt dome model (SD1) and dislocated salt dome model (SD2) into VRML or GOCAD. sd1-mod.h, sd2-mod.h
Model with interface slitted by a curved
vertical fault (SLIT)
Western Bohemia a priori model (WB2)
- Transforming the surface and velocity sections into VRML or GOCAD. wb2-mod.h
- Kinematic hypocentre determination (minimum ray-theory travel times). wb2-loc.h
Model of a real geological structure (L7)
- Transforming interfaces in model L7 into VRML or GOCAD. l7-mod.h
- Generating PostScript files with the sections across model L7 displaying the P-wave velocities.
- Two-point ray tracing in model L7, adding rays to the VRML or GOCAD files with interfaces.
Gridded 2-D Marmousi model and INRIA
bench-mark versions of the 2-D Marmousi model (MAR)
- INRIA bench-mark versions of the Marmousi model
- Generating PostScript files showing the P wave velocity sections in both INRIA bench-mark versions of the Marmousi model. mar-grd.h
- Calculating travel times in the INRIA Marmousi models
- Smoothing the Marmousi model for Gaussian-packet migrations.
- Optimization of the Shape of Gaussian Beams in the smoothed Marmousi model.
- Decomposition of the wave field into optimized Gaussian packets.
- Gaussian packet migration in the smoothed Marmousi model.
- Zero-offset ray tracing in the smoothed Marmousi model.
- Versteeg, R.J. & Grau, G. (1991): The Marmousi experience. Proc. EAGE workshop on Practical Aspects of Seismic Data Inversion (Copenhagen, 1990), Eur. Assoc. Explor. Geophysicists, Zeist.
Unconformity 2-D model (U2D)
- Generating PostScript file with the section across the model U2D displaying the P-wave velocity. u2d-grd.h
- Performing 2-D two-point ray tracing and generating synthetic seismograms with no attenuation, noncausal attenuation, and causal attenuation. u2d-ss.h
- Performing 2-D two-point ray tracing and plotting travel times. u2d-tt.h
- Comparing ray-theory and finite-difference synthetic seismograms. u2d-fd.h
- Generating system of equations for travel-time inversion. u2d-inv.h
- Cormier, V.F. & Mellen, M.H. (1984): Application of asymptotic ray theory to vertical seismic profiling. In: Toksoz, M.N. & Stewart, R.R. (eds.), Vertical Seismic Profiling: Advanced Concepts, pp. 28-44, Geophysical Press, London.
1-D model (RM)
- Comparing ray-matrix and 2-D finite differences seismograms in 1-D model RM. rm-fd.h
Weakly anisotropic models
(QI, QIH, QI2, QI4, QI8, SC1_I, SC1_II, KISS and ORT)
- Computing coupling ray theory and four kinds of quasi-isotropic ray theory synthetic seismograms. Calculating second-order perturbations of travel times. qi-ss.h
- Running history file 'qi-ss.h' for four different models, which differ in the degree of anisotropy. Calculating travel times by program ANRAY, and comparing the results of ANRAY and CRT. qi-ss4m.h
- Test of anisotropic common S wave ray tracing in different models. qi-acr.h
- Computing isotropic, anisotropic, coupling ray theory, and prevailing-frequency approximation of the coupling ray theory synthetic seismograms in the model with a very weak anisotropy. qih-ss.h
- Computing anisotropic, isotropic, coupling-ray theory, and prevailing-frequency approximation of the coupling ray theory S-wave synthetic seismograms in models QI, QI2 and QI4. Comparing the synthetic seismograms with package FORT and with Fourier pseudo-spectral method. qi1-ss.h, qi2-ss.h, qi4-ss.h
- Computing anisotropic ray theory S-wave synthetic seismograms in models SC1_I, SC1_II and ORT using package ANRAY. Comparing the synthetic seismograms with Fourier pseudo-spectral method. sc-ss-an.h
- Computing coupling-ray theory and prevailing-frequency approximation of the coupling ray theory S-wave synthetic seismograms in models SC1_I, SC1_II and ORT. Comparing the synthetic seismograms with package FORT and with Fourier pseudo-spectral method. sc-ss.h
- Computing coupling-ray theory and prevailing-frequency approximation of the coupling ray theory S-wave synthetic seismograms in model KISS. Comparing the synthetic seismograms with package FORT and with Fourier pseudo-spectral method. kis-ss.h
- Computing prevailing-frequency approximation of the coupling-ray theory S-wave Green tensors along common reference anisotropic S-wave rays in models QIH, QI1, QI2, QI4, KISS, SC1_I, SC1_II and ORT using the program CRTPFA. Calculating synthetic seismograms from the obtained Green tensors and comparing them with synthetic seismograms obtained by program GREEN. Interpolation of prevailing-frequency approximation of the coupling-ray theory within ray tubes. qih-pfa.h, qi1-pfa.h, qi2-pfa.h, qi4-pfa.h, kis-pfa.h, sc-pfa.h
- Calculating anisotropic rays in model SC1_II using the package CRT, displaying the calculated rays in VRML or GOCAD. sc2-ani.h
- Triangularizing the phase-slowness surface and the ray-velocity surface in model SC1_II using program ANISRF and displaying them in VRML or GOCAD. sc2-srf.h
- Determining the reference TI symmetry axis in model SC1_II. tidemo.h
Sample synthetic 3-D model (98)
- Sample computations in the model 98 (generating PostScript figures of velocity sections, transforming surfaces into VRML or GOCAD, calculating multi-valued travel times, generating synthetic seismograms)
1-D anisotropic "twisted crystal" model (TC)
- Analytically computing propagator matrices in model "simplified twisted crystal", and comparing the results with Green functions computed by CRT. Comparing the analytical solution with finite-difference solution in the frequency domain. Generating synthetic seismograms and plotting a figure of comparison of different ray-tracing methods. tc.h
- Analytically computing exact propagator matrix in model "oblique twisted crystal", and comparing the results with different quasi-isotropic approximations of the coupling ray theory computed by CRT. Generating synthetic seismograms and plotting a figure of the comparison. tco.h
Simple smooth 3-D model (N2)
- Calculating velocity isolines in 2-D sections. Computing rays and travel times by network ray tracing. n2-net.h
- Klimes, L. and Kvasnicka, M. (1994): 3-D network ray tracing. Geophys. J. int., 116, 726-738.
2-D representation of the Kummer random medium (RAN)
- Generating a 2-D representation of the Kummer random medium and calculating first arrival travel times. ran-net.h
2-D model with a salt body (HESS)
1-D constant velocity gradient model (VGR)
- Iterative network ray tracing within Fresnel volumes. fv-net.h
- Numerical calculation of geometrical spreading from gridded slowness vectors. vgr-q2.h
- Podvin, P. & Lecomte, I. (1991): Finite difference computation of traveltimes in very contrasted velocity models: a massively parallel approach and its associated tools. Geophys.J.int., 105, 271-284.
SEG/EAGE Salt Model (SAL)
- Aminzadeh, F., Brac, J., Kunz, T. (1997): 3-D Salt and Overthrust Models. SEG/EAGE 3-D Modeling Series No.1., Soc. Explor. Geophysicists, Tulsa.
2-D model Pluto 1.5 (PLU)
Computation of R/T coefficients
Models of the Cotton Valley site (CV)
Model with planar interfaces (EX)
- Transforming the model into VRML or GOCAD. ex-wrl.h
- Performing 3-D two-point ray tracing for given source and receiver profile. ex-crt.h
- Running history file 'ex-wrl.h', and then running history file 'ex-crt.h' for three different source and receiver profile positions. ex.h
Correlation functions of random media (CORFUN)
- Generating PostScript figures of random functions with different correlation functions using 2-D program 'grdran2d.for'. corfun.h
- Generating and plotting representations of random functions with different correlation functions. Calculates the same figures as 'corfun.h' but using 3-D programs 'grdran.for', 'grdfft.for', 'grdcor.for', 'grdcal.for' and 'grdstat.for'. corfft.h
- Calculating the von Karman medium correlation function by FFT (programs 'grdfft.for', 'grdcor.for', 'grdcal.for') and comparing the result with analytic solution calculated by 'grdckn.for'. cknfft.h
2-D model P1I with reflection surfaces (P1, P1I)
- Constructing the smooth model - model P1. p1-inv.h
- Constructing the model with interfaces - model P1I. p1i-inv.h
- Calculating the velocity differences in the models. p1-dv.h
- Calculating synthetic seismograms simulating a reflection measurement. p1i-ss.h
- Computing 3D seismograms using 2D ray-based Born approximation
in heterogenous model P1-8-10%. The background (unperturbed) model
is heterogenous smooth model P1 without interfaces.
Main history file to run history files 'p1-grid.h', 'p1-mtt.h',
'p1-iwf.h', 'p1-born.h', 'p1-ss2.h' and 'p1-ss.h'.
p1-borna.h
- Computing the elastic parameters at the gridpoints in both unperturbed and perturbed model and the perturbations of these elastic parameters. p1-grid.h
- Computing the Green functions from the source and from the receiver, slowness vectors, travel times and other quantities at the gridpoints. p1-mtt.h
- Computing the incident wavefield necessary for the Born approximation using the representation theorem. p1-iwf.h
- Computing the 2D Born approximation. p1-born.h
- Generating the ray-theory seismogram. p1-ss2.h
- Generating the Born seismogram from RF format file computed by history file 'p1-born.h' and visualizing it together with the ray-theory seismogram computed by history file 'p1-ss2.h'. p1-ss.h
Simple models to test the Born approximation
- Running history files 'm2d-mtt.h', 'm2d-iwf.h', 'm2d-born.h',
'm2d-ss2.h' and 'm2d-ss.h'.
m2d-main.h
- Computing the elastic perturbations, the Green functions from the source and from the receiver, slowness vectors, travel times and other quantities at the gridpoints. m2d-mtt.h
- Computing the incident wavefield necessary for the Born approximation using the representation theorem. m2d-iwf.h
- Computing the Born approximation. m2d-born.h
- Generating the ray-theory seismogram. m2d-ss2.h
- Generating the Born seismogram from RF format file computed by history file 'm2d-born.h' and visualizing it together with the ray-theory seismogram computed by history file 'm2d-ss2.h'. m2d-ss.h