* '''If''' it is characterized by regional onlap above and truncation below '''then''' it is probably a sequence boundary
+
* '''If''' it is characterized by regional onlap above and truncation below '''then''' it is probably a [[Definitions_of_depositional_system_elements#Sequence_boundaries|sequence boundary]]
* '''If''' it is characterized by regional downlap '''then''' it is most likely a downlap surface
* '''If''' it is characterized by regional downlap '''then''' it is most likely a downlap surface