Then, make the file "project" (you can save this file in any name you want.) executable by unix shell command: chmod +x project
Now, you can run project in your home directory with "./project"(use
"./" in case that there is any executable file
with the same name in other directoryies within your search paths.) A project
working directory "/gg522/proj1" will be generated
at your home directory, and the GUI interface will be loaded.
A. Load Data
B. Display Data
C. Preprocess Data
D. Pick data
E. QC Data
F. Invert Data
G. Forward Modeling
H. Documentation
I . Quit GUI
In this lab, you only need to use "Invert Data " button, click on it and click on the choice "Units in meters" or "Units in feet" according to your data. The interface for inversion will be loaded.
Clicking on the "Quit GUI " button will close all the interfaces.
2. Inversion Interface
This interface includes several menu choices, let's go
through them one by one:
(1) Dynamic Schedule:
Interactive module for dynamic
smoothing schedule for the inversion. (From large scale smoothing to small
size smoothing based on idea of resolving large scale structure first,
then dealing with fine structure.). You can set up to 8 smoothing
schedules.
Parameters for each page
of the schedule setting ( You can click on "help"
button for the information)
Iteration | Number of iteration for each smooth schedule. |
Grid spacing | Grid size for forward problem. |
Vtop | Velocity for the top of initial model in inversion. |
Vbottom | Velocity for the bottom of the initial model. |
Vmin | Estimated minimum value of velocity allowed in inversion. |
Vmax | Estimated maximum value of velocity allowed in inversion. |
Nite | Number of shots used to calculate the step length. |
Ndown | =1, downward extrapolation of gradient;
=2, downward extrapolation of slowness. |
Irsx | Number of grid involving in smoothing in x (horizontal) direction. |
Irsz | Number of grid involving in smoothing in x (horizontal) direction. |
(3) Show input data:
Plot travel time curve
(t-x) and shot-receiver geometry in CSG/CRG.
(4) Starting model:
Show initial model
will be used in the inversion code:
model 1 (Gradient model if Vtop);
model 2 (homogeneous with v=Vtop);
model 3 (homogeneous with v=Vbottom).
where Vtop,
and Vbottom are from the smoothing schedule.
(5) Start inversion:
Run inversion Fortran
code "refra-2d-pq.f".
submenu:
From beginning:
Run inversion from scratch;
Continue...:
Continuing the calculation from the results got before.
Note: If you changed "coord.temp" during the inversion, you have to run inversion from beginning to honor the new geometry in the "coord.temp".
(6) Show Results:
Showing the inversion results
such as velocity model, residual, and histogram of the residual distributions.
submenu:
Velocity Field | Final result: Final result of velocity with raypaths.
Dynamic result: Velocity field for every smooth schedule. |
Histogram | Final result: Histogram of final residuals of traveltime.
Dynamic result: Histograms of residuals for every smooth schedule. |
Total Traveltime Residual | Behavior of residuals of traveltimes with respect to the number of iterations. |
(7) Forward velocity model:
Show forward model set in
'Forward Modeling'. We do not use this here.
(8) Save Figure
Save figures using Matlab
"print" function.
(9) Close Figure
Close current figure.
(10) Zoom, Zoom off, Zoom out
Zoom the figures, same as
Matlab commands.
(11) Quit: Quit Inversion Interface