Stacking

Description Create 2D and 3D volumes from gathers by stacking traces.
Module(s) Explorationist, Image Gather Processing
Requirements Gathers, Mutes (optional)
Related Angle Stacks
Works with Gathers

This process creates stack volumes from gather data according to the specified stacking mode, optionally applying an inner and/or outer mute.

Apply positive and negative offset limits to define the included range of offsets. Traces with offsets outside these limits will be ignored.

Create a Stacking process

Create stacking process
  1. In the Control Panel, open the Process tab.
  2. At the tab header, click the Add icon and select New Process.
  3. Scroll down and double-click on Stacking.
  4. Type a name for the process and click OK.

Configure the Stacking process

Define stacking parameters
  1. In the Details Panel, select the gather Volume.
  2. If mutes are not specified, all traces in the gather are stacked.
  3. Select the Inner/Outer Mute to apply before stacking
  4. Enter the Ramp Distance (m).
  5. At Stacking options (muted zones and NaNs are ignored):
    • Standard — (Σ x) / n
    • Root N — (Σ x) / √ n
    • Square of sum of square roots — Σ (√ x)2 / n
    • Offset — (Σ (x * offset(x))
    • Blackman — Same as offset, with the input values being weighted by a Blackman window rather than the offset, such that the near and far offset values are damped relative to the mid-offsets.
    • Hamming — Same as Blackman mode, with a Hamming windowing function used in place of the Blackman windowing function.
    • Median/mean — Returns the mean of the values within "percentile" of the median
    • No fold compensation — Σ x      

Note: When the trace values are weighted (by either the offset or a Blackman/Hamming taper), these weights are normalised prior to stacking.  

  1. Optional positive and negative offset limits determine the range of offsets which will be considered
    • Traces with offsets outside these ranges will be ignored.
  2. Offset source:
    • Use the OFFSET header
    • Calculate offset from SX/SY/GX/GY: Calculating offset from the SX, SY, GX, GY headers (honouring the SCALCO header).    

 

If mutes are applied, weights from ramped or smoothed regions are included in the stacking normalisation.      

Output traces have their NHS header set to the number of live traces that contributed to any sample in the stacked trace.   

Tip: To quickly open the output volume, right-click the process item in the Process tab and click Open Child Volume. Vice versa, you can also open the process from the Volume tab directly. To do this, right-click the volume which was created from a process (indicated in italics) and click Open Parent Process.