Description
High resolution radon spectrum multiple wave attenuation
This module used for multiple wave attenuation in unstacked NMO (normal move out) corrected seismic gathers.
An unstacked seismic common-midpoint gather can be described in terms of slope d t/d x= pand intercept time τ, the arrival time obtained by projecting the slope back to x= 0, where xis source–geophone distance. The transform process is called the Radon transform. The Radon transform distinguishes between primaries and multiples based on the residual move out from near to far offset. NMO corrected gathers will align all of the primary energy near P=0, giving greatest weight to the primary reflections in the sparse transform. Multiple energy should be expected to Radon/Tau-P fall on a variety of P-values. The greater the move out differential produces the more effective the Radon filter.
The module computes multiple waves model and primary waves model. This procedure based on decomposition seismic data into user-defined parabolas and produced by anti aliasing least-square method with high resolution. Waves according to the big slope parabolas detected as multiple waves. Waves according to the small slope parabolas detected as primary waves. User defines border between multiple and primary waves.
Comment
Input seismic gathers must be NMO-corrected, CMP-Offset sorted, applied all static corrections.
Parameters
P min
Minimum p-value for transform data from t-x into tau-p domain.
P mid
Middle p-value for transform data from t-x into tau-p domain.
This parameter is start for modeling multiple waves.
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.
Taper P
Taper zone between P min/mid/max-values.
Taper Tau
Taper zone between start time - filtered - end time.
TimeOffset
Time varying reference offset for multiple modeling.
Time– time.
Reference offset– reference offset.
Frequency min
Minimum frequency for filtering
Frequency max
Maximum frequency for filtering
Pre-Whitening Factor
Pre-whitening factor for stabilizing tau-p to t-x transformation.
Use AGC
Apply automatic gain control pre radon filtering and remove after radon filtering.
AGC Window
Window for automatic gain control.
Use mask mute