# Anisotropic Model Conversion

 Description Convert between any combination of the interval quantities. Module(s) Image Gather Processing, Gather Attributes, Explorationist Requirements Gathers, Velocity Model Related Workflows Works with Gathers

Anisotropic Model Conversion allows for conversion between any combination of the interval quantities below:

• Vertical velocity V0
• NMO velocity Vnmo
• Delta δ
• Epsilon ε
• Eta η

The process automatically determines which outputs are possible and computation is performed via the formulae Vnmo = V0 sqrt(1 + 2δ), and η = (ε - δ) / (1 + 2δ). Inputs may be in-depth or time, but they must all be in the same domain. Outputs may also be in either depth or time. Note, however, that all operations are performed in the time domain. Therefore, if inputs are in-depth, V0 must be provided, and if inputs are in time but outputs are in-depth, then it must be possible to calculate V0. Input volumes are prioritised as output in the case where it is possible to compute them from a combination of other inputs.

When run in a workflow, the user must specify the input parameter and the desired primary output parameter. If the process is the last in a workflow then all outputs will be written to disk by default, but this behaviour can be modified through the Advanced section of Job Configuration and Creation in the main workflow panel.

## Create an Anisotropic Model Conversion 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 or type in Anisotropic Model Conversion.
4. Type a name for the process and click OK.

## Configure the Anisotropic Model Conversion process

1. Enter the input parameters:
• V0: Input the interval vertical velocity.
• Vnmo: Input the interval NMO velocity. Note that this is the interval NMO velocity, it can be derived from NMO used for moveout via the velocity conversion process (vrmst -> vintt).
• Delta (δ): Input the interval delta.
• Epsilon (ε): Input the interval epsilon.
• Eta (η): Input the intrinsic eta. This can be derived from, say, effective eta and NMO velocity via the Eta Conversion process.
2. Output can be optionally selected by clicking the preferred result checkbox.
3. Type in the Output Vertical Sequence.
4. Vertical interpolation: Input the vertical interpolation method to use for interval properties, and for the velocity used for time-depth conversion. The two options are:
• Interval Conversion (Blocky)
• Interval Conversion (Smooth)