The velocity models is crucial in seismic imaging as it controls the quality of the migrated image and it is also crucial for time to depth conversion. Surface seismic in principal measures mainly the horizontal velocity component and sonic logs measures the vertical velocity component of the earth. The ratio of these velocities creates anisotropy. The term ‘provelocity’ will be used in the present work specifically to denote the parameter derived seismic processing as ‘velocity’ because this is a modelling parameter that can be quite different from the true propagation velocity in the ground (Al-Chalabi, 1994), (Ghazali, 2006). Much of the information about the velocity distribution in the ground is derived from NMO stacking (maximum coherency stack) provelocity, Vmcs. These stacking provelocities are used as basis for estimating the root mean square ‘RMS’ provelocities and are often treated as being synonymous to each other. The difference between the root mean square and average velocity depends on the parameter known as the heterogeneity factor. The heterogeneity factor is a positive quantity being near to zero only when all of the layers have the same velocity as it is close to homogeneous. Its value is independent of the order of layering. Therefore the rms velocity equals the average velocity when the ground is homogeneous (Robein, 2003).


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error