Top

Pick represents the top of a formation (Geologic Unit).

Base

Pick represents the base or bottom of a formation (Geologic Unit).

Marker

A recognizable marker (marker bed) used for subsurface correlation.

Unconformity

Informal feature where some stratigraphic section is absent due to an unconformity. An informal name is assigned (except for the Mississippian-Pennsylvanian unconformity which is treated like a Strat Pick). For instance, Unconformity “A,” Unconformity “B.” Such designations do not imply regional correlation. This value has not been assigned to wells in the PDMS.

Fault

Informal feature indicating where a fault intersects a well bore. An informal name must be assigned. For instance, Fault “A,” and Fault “B.” Such designation does not imply regional correlation.

Total Depth [Pick Type]

The measured total depth, Total Depth may be listed as a Strat Pick, but only for deviated holes (horizontal or directional wells).

Position

The pick formation is vague or absent and a "phantom pick" position has been assigned for interpretive purposes.