The Occurrence/Occurring Distinction

It has been contended that an event as a whole does not occur but, rather, is only occurring when any one of its temporal parts occurs1 I shall consider here the mereological implications of drawing a distinction between the time of an event’s occurrence- its duration- and the times of its occurring- the duration of any one of its proper temporal parts. In particular, I intend to see whether it allows one to avoid having co-located events in one’s ontology.