Abstract
Stacking velocities is input when creating a velocity cube. It is thus of great importance that the quality is good so the use of the velocity cube in depth conversion can be reliable.
One source of error can be misties in stacking velocities; i.e. crossing lines of stacking velocities show different values in the crossing points.
This documentation tells how you can correct misties in stacking velocities so the crossing stacking velocity lines will match.
Example of misties in stacking velocities
The misties can be corrected if the stacking velocities are regular.
On this page:
Regular stacking velocities
The concept regular stacking velocities means a set of survey lines where all lines hold the same number of vertical values in regular depth or time positions. If not regular, use the command object Make regular stacking velocity to transform the stacking velocity dataset.
In many cases the stacking velocities are already in a regular form. But some typical cases where it is not are when two set of stacking velocities from different surveys shall be merged and there are obvious misties. In those cases it it necessary to make all the stacking velocity data regular with the same number of vertical registrations.
Menu for transforming stacking velocities to a regular form
Adjusting misties in stacking velocities
Activate the command object Adjust stacking velocity lines found under the entry Regular Stacking Velocities.
It is also possible to have a weight factor when doing correction. It should be applied if the adjustment has to be performed on both crossing sections, f.inst. 0.7 on one and then no adjustment using the other as input.
Command objects for adjusting misties in stacking velocities
Result of mistie corrections
The correction was done with the menu Adjust stacking velocity lines. Be sure to have the parameters correctly set and click Execute.
The corrected stacking velocities are now better suited to be gridded into a velocity cube.
Stacking velocity after correcting for misties
Options in mistie corrections
There are other features and options within the mistie correction concept. Especially if one wants to regulate the stacking velocities for a section within a vertical area described with a digitized boundary. In that case read the article Working with regular stacking velocities.