It is common in some projects to have a few horizons that have dense data in depth and other horizons that have very little data. In these cases, the sparse data may be measured as thickness from the better defined horizons and the user is faced with how to use this in EarthVision. The illustration below shows just such an example, where an intermediate horizon has been created using a thickness grid between two existing horizons. The use of thickness data can also occur when geologists prefer to create new horizons using independent thickness grids to stack up or down from a reference horizon. First, it is important to review the use of reference and intermediate horizons in the WorkFlow Manager and the Geologic Structure Builder.
Positive values represent a vertical distance from the reference horizon.
The larger the value, the farther from the reference horizon. Zero or negative values indicate an intersection of the intermediate and the reference horizon. The option of using a 2-D grid as a percentage grid is also currently supported in this program. It should also be noted that the operations involving thickness constants and grids are isochore operations in that thickness is added in the vertical direction. While the general process of using thickness data in the WorkFlow Manager and Geologic Structure Builder is very straightforward, there are some special caveats and techniques to handle special situations.