The Angle Stacks process creates angle stacks from a gather volume using a velocity model. Different muting and stacking options are available.
- In the Control Panel, open the Process tab.
- Click the blue "+" icon and select New Process.
- Search and double-click Angle Stacks.
- Type a name for the process and click OK.
Select the Gather and Velocity Volume.
- If you provide offset gathers, a velocity model is required to calculate the paths of the angle mutes.
- At Velocity Type, select the type of velocity used in the process.
- Select the Velocity Units.
- At Velocity smoothing length (ms), additional smoothing can be applied to the velocities before use (for more information regarding this parameter, see Creating an Angle Mute).
- (Optional) specify a Inner Angle Protection and/or Outer Angle Protection to apply offset-domain mutes.
- Inner Angle Protection: Offsets above this value will not be muted by the inner angle mute
- Outer Angle Protection: Offsets below this value will not be muted by the outer angle mute
- Set the mute Ramp Distance to taper the mute.
Stacking options: choose a stacking mode and define the positive and negative offset ranges (see Stacking for more information).
- 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: As for Blackman mode, with a Hamming windowing function used in place of the Blackman windowing function.
- Median/mean: Returns the mean of the values within 'percent to keep' of the median where, for example, 70% will eliminate the lowest 15% and highest 15% percentiles from the mean calculation.
- For each angle stack to generate:
- Click the blue "+" button
- Name the stack: e.g. Near, Mid and Far.
- Enter the Inner stacking angle (between 0 and 90 degrees)
- Enter the Outer stacking angle (between 0 and 90 degrees)
- Click the red X to remove a stack
- One angle stack is created in the Volume tab for each row