Geoscience Ontology
A feature is ontologically dependent on at least two distinct things, a host and some essential part, and emerges from some relation holding between them. E.g. hole is hosted by some material entity and has spatial regions as parts (with regions changing as the host moves in space), and emerges from a spatial relation (adjacent containment) between them. A feature is made of parts of the same type, either endurants, perdurants, or possibly situations, so each feature is then itself also a perdurant, endurant or situation, e.g. a hole is also a spatial region.