Visual Sunt

 

 

Seismic reflection processing steps (Processing software Visal SUNT 22)

1 Reformat: Conversion from seismograph format (SEG2) to software format (Seismic Unix)


First of all, data structure has to be converted from seismograph format, usually SEG2, to processing software format: SU / SEG-Y

2 Visual data control

A quick overview of all data is strongly recommended

3 Geometry input

The first step is to enter the geometry and coordinates acquisition stations

4 Geometry control

Controlling the geometry is very important because an error has catastrophic repercussions on the subsequent treatment.

(Red=shot point Yellow=Receivers, 1 line = 1 shot)

5 Kill noisy traces

We must eliminate the traces noisy or dead

6 Frequency spectrum

A frequency spectrum used to select the filter settings to be applied.

7 Data frequency filtering

Applying a frequency filter

8 Gain recovery

Gain recovery using sliding windows (Calles AGC)

9 SORT, traces grouped by CDP

The traces are reorganized by CDP instead of a distribution by record

10 Velocity scan

Determining a velocity model by CDP and depth is a crucial step in the processing chain. Velocity Scan the method

is well suited for shallow high resolution seismic.

 

11 Normal Move Out: hyperbola correction

 

Knowing the velocity distribution, it is possible to recover the traces according to their distance, making it flatten

the reflection hyperbolas. This operation is called Normal Move Out

12 STACK: add traces with the same CDP

All traces are from the same CDP added. This operation called STACK improves the coherency of the signal and reduces random noise

13 Trace mix and gain

Stack section finally is improved with a frequency filter and a trace mix, average amplitudes of adjacent traces

14 Final interpreted time section

The time section is interpreted by geologist 15 Depth section and Time section

 

Finally a depth section is computed using the velocity model. A demo version of Visual Sunt can be downloaded

(Free use for 15 days with your own data set)

Visual Sunt-Demo