Semblance plot

[Mohamed]

Can somebody please explain to me what the semblance plot is (in a simple way, please ).

[eric2009]

It looks like a tough question, no one has answered it.

[Mohamed]

It looks like a tough question, no one has answered it.

When I received the E-mail notification about your reply, I was like "Uhh, finally some one has answered my question".

[Simon]

I heard this term long time ago in a lecture, got a feeling that it sort of works like the migration in the GPR/seismic data -- make the picture clearer to identify features.

[Mohamed]

“The semblance plot is a hyperbolic Radon transform, in which the amplitudes are smoothed, scaled, and contoured to produce a visual display. This transformed display has axis of time and velocity that are used to identify the velocities for normal move-out (NMO) correction of the CMP gathers. The hyperbolic move-out energy from primary reflections, multiples, and mode converted energy is focused to a small local area on the semblance plot, with its peak defining the move-out velocity.” (Bancroft & Cao, 2004).

An example of a Semblance plot is shown below:

Tags: what, is, Semblance, plot.

[Tyler]

To make it simple: in order to do proper stacking of CMP gather of seismic reflection data, the 1D velocity model needs to be defined. The semblance plot is generated from the seismic data to visually help to generate the velocity model.