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Velocity Scanning Workflow

The purpose of this plugin is to improve imaging of seismic data below salt and in other hard to image structures. The technique used is to refine the velocity model iteratively by applying a constant percentage change (95%, 105%, etc.) to the initial velocity model. The seismic data is then migrated for each of the percentage velocities and the various migrated panels are scanned and picked along a horizon of interest, to select which percentage velocity focuses the energy better. A new velocity model is then derived from this process.

Some of the main steps of this workflow include:

Migration of the seismic dataset with the 100% velocity model and some variations (95% and 105% for example). This step is done outside INTViewer. Loading of the migrated datasets and the 100% velocity model. A different color is assigned to each migrated dataset (corresponding to a specific percentage of the 100% velocity) Loading of a reference horizon (velocity has been perturbed only below this reference horizon) Picking along a horizon using the migrated panel where the event energy is better focused. Each pick will be displayed in the color assigned to the percentage velocity. As the user picks, a new velocity model is calculated on the fly, by first interpolating the picks along the horizon, and then by interpolating and scaling the velocity vertically. Different interpolation algorithms have been implemented, including bi-linear, bi-cubic and natural neighbor. The user can save the new velocity and repeat the process for a deeper horizon.