Depending on the type of geophysical data, the array increments may be time, distance, or velocity. Select the appropriate type or one that fits your processing goal. Doing so will refresh the topmost entry label, indicating the array size.

The list of options includes:

• None: Base property not assigned.
• Energies: Specify the value of the first element of the array and the array increment. The table in the lower part of the dialog will automatically update to show the association of indices with energy.
• Frequencies: Specify the frequencies for each array element. These frequencies are tabulated in the dynamic table in the lower part of the dialog.
• Time windows (contiguous): Specify the time gates as a set of consecutive widths. Repeated widths can be entered using the concise syntax n x m, where width m is repeated n times. If the number of provided time windows is less that the dimension of the array, the last width is assigned to the remaining array elements. The dynamic table in the lower part of the dialog, tabulates the time widths (Width) and the centre value of each time gate (Time). See illustration.
• Time windows (discrete): Specify the time windows as a set of start and end times. The end of one time gate may overlap with the beginning of the next. These times are tabulated in the dynamic table in the lower part of the dialog. See illustration.

Specifying the units is optional. The drop-down list will be populated based on the Base selection.

The label of this entry is contextually set and depends on the nature of the Base parameter. The first element of the array may not be at zero. Initial value, Delay time, and Base frequency define the gap to the first element of the array. This attribute is stored in the data array header.

The label is contextually set relative to the Base parameter. You can enter the property increments in a few different ways.

Time windows is a special case generally used in IP. In this instance, both the intervals and the cumulative time are displayed.

The Increment parameter allows you to define the increments of the selected base property.

The vertical axis of the Depths attribute increases downwards, while the vertical axis of the Elevations attribute increases upwards. Although you are not prevented from defining the Depths attribute with a negative increment, you are discouraged from doing so because this combination is equivalent to defining the Elevations attribute with a positive increment.

This button will appear only if there is at least one other array channel of an equal dimension that carries a base property.

If there is only one other such array, the name of the array will be shown on the button, otherwise clicking the button will pop up a list of arrays with on-board properties to choose from.