vmed

The primary motivation for vmed was to design a graphical, interactive velocity model editor that would be, for many operations, easier and faster then editing a v.in file with a text editor. This becomes even more important as the v.in file becomes large. Of course, for some simple operations it will likely be just as easy, or easier to edit the v.in file the old-fashioned way. But not as much fun.

Some of the things you can do with vmed:

(1) Analysis, visual inspection of the velocity model

• Colorize the model according to velocity, vertical or horizontal gradient, or by layer
• Create postscript plots of the model
• Get velocity, vertical 2-way traveltime, vertical gradient or horizontal gradient at any point
• Get detailed information about each model block
• Toggle plotting of boundary and velocity nodes, vertical model boundaries
• Check for negative velocity contrasts across boundaries, negative vertical velocity gradients, crossing boundaries, pinched out boundaries and more
• Plot velocity contrasts across model boundaries and dips of layers
• Grid the model and save the grid to either a binary file or an ascii file suitable for plotting using GMT
• Overlay velocity contours
• Plot model boundaries versus vertical 2-way traveltime
• Plot 1-D velocity profiles at any location
• Zoom in/out

(2) Interactively edit the velocity model

• Move and delete boundary and velocity nodes
• Add or delete layers
• Duplicate a layer (creates a new layer with the same boundary as a specified layer)
• Shift layer boundaries vertically
• Easily edit the X and Z coordinate and inversion switch setting of a boundary node, or the X coordinate, velocity and inversion switch setting of a velocity node
• Simultaneously change the depth of all boundary nodes in a layer by a specified amount, or assign a constant depth to all nodes
• Simultaneously change the velocity of all velocity nodes in layer (either upper or lower or both) by a specified amount, or assign a constant velocity to all nodes
• Simultaneously change the inversion switch setting of all boundary nodes or velocity nodes in a layer
• Create pinch outs (a part of a boundary can either be pinched up or down)
• Change the X-limits of the model (either extend the model at either or both sides, or "crop" the model), and/or change the Xmin value (i.e., X coordinate of the left side of the model)
• Save the model to a specified file name

Yes, if you are a rayinvr animal, (a) you have my condolences, and (b) this program is for you.

Download compressed UNIX tar file (88 Kb) - Most recent update: Feb 21, 2004

You can also obtain vmed via anonymous ftp. Computer = ftp.soest.hawaii.edu; directory = bzelt/VMED; file = vmed.tar.gz.

Online Documentation:

Documentation/examples for edit mode.

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