Missing thickness values

Missing values in the thickness column on the Refine Selection form, are marked by the cannot calculate icon , can have multiple reasons:

Apparent thickness You selected to honor the fault model (option on the Assign Data form) and the projection identified that a fault is present at the marker pick location. Fault offset can result in stratigraphic doubling or reduction.
No intersection One of the selected events is a surface (i.e. a tri-mesh or 2D grid), but the wellbore has no intersection with that surface. Possible reasons can be that the surface is not defined at the well location (it is laterally less extensive), or the well is not deep enough.
Negative thickness The depth of the base event is above the depth of the top event, resulting in a negative thickness.

Handling of missing values

You can react on these situations differently. All cases are treated by default in such a way that the wellbore is excluded from the thickness map creation. You can decide to use the location by manually entering an anticipated value. After clicking Apply or OK, the changes are saved and reflected in the Thickness/Trend Map.

In case of a missing surface, you can choose to ignore the well location by leaving the row unchecked. Alternatively you can enter a value which you believe corresponds to the overall thickness. This can be handy if you want to steer the thickness map in an undefined section.