4D Processing Technology

Optimal 4D processing is ensured by the combination of experience and expertise, careful processing, and optimal processing tools.

Processing Tool Box

Our comprehensive set of high fidelity algorithms allows us to quantify amplitude, time and phase of various data vintages by employing complex correlation analysis. PGS offers an extensive set of 4D-friendly algorithms.

4D Quality Control & Repeatability Analysis

Quality control in conjunction with 4D processingQC, including horizon and volume-based attributes, are performed after each major processing step:

• RMS calculations
  • Normalised RMS difference (NRMSD, “repeatability”)
  • RMS ratio
• Complex cross-correlation analysis
  • Maximum cross-correlation coefficient (“predictability”)
  • Phase rotation
  • Time shift 

The attributes are calculated either along horizons, fixed time windows or volume-based.  The review of these attributes is then integrated into holoSeis^TM. This approach allows the display of Base and Monitor 3D volumes, calculation of the difference volumes on the fly whilst overlaying the 4DQC attributes. Attribute maps and histograms are also used routinely.

Spatial cross-correlation analysis and spectral coherency are also pursued when appropriate.Well log information also can be incorporated into the 4D analysis where appropriate.

       

4D QC process flow and holoSeis 4D attribute QC display.