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g-Platform provides several radon modules:

•Radon multiple attenuation: vista views: input, output, difference gathers, user-defined time curves on gather;

•Radon - TauP - High resolution: vista views: input, output, difference gathers, Tau-P domain, interactive curve on gather;

•Radon - TauP: vista views:  input, output, difference gathers, Tau-P domain, interactive curve on gather;

•Radon multiple attenuation by velocity: vista views: input, output, difference, NMO-corrected gathers, interactive velocity spectrum for constrain-polygon picking;

•Radon - by picking: vista views: input, output, difference gathers, interactive Tau-P domain for constrain-polygon picking.

 

If you are not happy with one result, try another module or mix them and create a complex workflow.

 

                     Radon multiple attenuation                    

This module transforms seismic traces into Tau/P (intercept time and slowness dt/dx = p) domain where we can easily separate multiples and primaries. Such separation allows to attenuate energy of multiple waves before reverse transformation into time domain (T-X). Basic idea is separation primaries and multiples by their velocity (moveout). Input traces are decomposed so hyperbolic events map to elliptical curves in Tau-P domain.

Input seismic gather must be sorted by Common Middle Point (CMP) - Offsets and the primaries should be flattened by applying Normal Move Out (stack velocity) correction before Radon transform. In this case the primary energy will be near P=0, which produces difference in moveout makes it possible to flatten the primary reflections while leaving the multiples under-corrected with a moveout approximately parabolic.

                                                                  Slowness = 1 / Velocity

                 

       

Model of CMP gather: 1) Time domain (T-X): Primaries+Multiples;

                                       2) Tap-P domain: Primaries+Multiples:

                                       3) Time domain (T-X): Primaries.

 

The module performs a model of primary and multiple events. This computation is based on data decomposition into user-defined parabolas and calculated by high-resolution algorithm, de-aliased least-squares method in the frequency space domain for every frequency of the pass-band which is defined by frequency min (Hz) and frequency max (Hz) parameters. Events corresponding to parabolas with a bigger curvature are considered as multiples. Events corresponding to parabolas smaller than this constrain are primary events. The area limits between primaries and multiples is user defined parametrization.

Parameters:

P min

Minimum p-value for transform data from t-x into tau-p domain.

P max

Maximum p-value for transform data from t-x into tau-p domain.

(Choose this parameter with care because run time for this process increases with the square of the  number of P-values).

Delta P

Amount of modeling waves.

Should be approximately equal signal response time interval.

 

 

Execute the module and open all vista windows: