PROCESS

QC/QA PRODUCTS

1) Reformat

2) Geometry

1)Farr Display

2) Display of offset limited (0-1000 meters) shot and receiver gathers with predicted first break time overlay

3) Shot and receiver quadrant stacks

3) Refraction Statics

1) Shot, Receiver and CMP stacks with and without refraction statics

2) Farr plot with refraction statics

3) Shot and receiver Quadrant stacks

4) Display shot and receiver statics

5) Display layer velocities and depths

4)True Amplitude Recovery

1) RMS amplitude curve before and after correction

2) Display a few test records before and after correction

5) Surface Consistent Scalars

1) Surface consistent amplitude display before and after surface consistent scaling

2) Shot, Receiver and CMP stacks

3) Display of Scalars

4) May have to apply surface consistent scaling after decon also

6) Noise Reduction

1) Display input, output and difference in test gathers and CMP stack in relative amplitude mode

2) May have to apply several noise suppression processes to handle different types of noise

3) May have to apply residual noise reduction after decon

4) Display amplitude and FK spectra before and after each noise reduction

5) Display S/N amplitude spectra

7) Surface Consistent Decon

1) Display spectral analysis

2) Display autocorrelations

3) Do not use spectral balancing for AVO

4) May have to apply CMP/CRP ensemble decon before or after PSTM

8) Surface Consistent Statics

1) Display shot, receiver and CMP stacks

2) Display surface consistent statics

9) Multiple Suppression

1) Display input, output and difference in test gathers and CMP stack in relative amplitude mode

2) Display amplitude and FK spectra before and after multiple suppression.

10) Velocity Analysis

1) Display inline, crossline and timeslice profiles of the velocity field.

2) Display NMO corrected CMP gathers or supergathers

11) DMO

1) Display offset bin fold or offset panel (for 2D) or time slices (for 3D) to determine size of holes in coverage

12) Prestack Time Migration

1) Display offset bin fold or offset panel (for 2D) or time slices (for 3D) to detrmine holes in coverage

2)PSTM to gathers at velocity locations for preliminary velan

3) PSTM to stack over velocity lines at 90-110% of above velocity at 2% increment in inline and Crossline directions

4) PSTM to stack over veloity lines at 95-105% of velocity from #3 above at 1% increments in inline and crossline directions

13) Merging datasets

1) Structure match QC with cross-correlations or trim stat

2) Character match (amplitude and phase)

3) Gain match (amplitude level)

Notes:

Conversion to minimum phase equivalent for Vibroseis data. Retain datatype flag for surveys with dynamite and vibroseis data.