Surface Consistent Processing
Surface Consistent Deconvolution
Modern processing workflows for onshore seismic acquisitions
include surface consistent (SC) deconvolution techniques. SC deconvolution
is used to counter the filtering effects of the source itself,
the receiver station (the summation of the individual geophone
responses, coupling, etc.) and the unique wave propagation effects
of the weathering layer(s).
Single-trace deconvolution creates operators which attempt to
remove the effects of the wavelet and flatten the spectrum. These
operators are sensitive to the noise on individual traces, and
errors in the output phase spectrum commonly occur.
Geotrace’s robust SC deconvolution techniques mitigate
these noise effects and stabilize the solution. Source, receiver
and offset terms are commonly employed for the surface consistent
solution. This implementation may also be constrained to design
operators on the band-limited signal component of the data only.
Surface Consistent Scaling
Relative amplitude processing is imperative for projects
proceeding through AVO/AVA analysis.
Surface consistent (SC) amplitude analysis and scaling is performed
to recover from the spherical divergence effects of the source
wavefield and the attenuation effects of the weathering layer(s)
at each unique source and receiver location.
Noise rejection is often required to attenuate as much noise
as possible prior to amplitude analysis. The measured amplitudes
from individual traces are reconciled to yield surface consistent
components for subsequent application to the data. The surface
consistent solution may be decomposed into 5 terms, i.e. source,
receiver, offset, CMP, and channel components.
As a surface consistent process, SC scaling is often performed
at multiple stages in the processing workflow. It is usually applied
pre-deconvolution, with subsequent analysis and refinement after
deconvolution, and after selected noise-rejection stages. In this
manner, a robust relative amplitude recovery result may be achieved
to satisfy the relative amplitude requirements of reservoir attribute
processing.
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