originate vs well up

originate and well up both are verbs.

Word	Noun	Adjective	Verb	Adverb
originate	No	No	Yes	No
well up	No	No	Yes	No

As verbs, well up is a hyponym of originate; that is, well up is a word with a more specific, narrower meaning than originate:

Other hyponyms of originate include resurge, come forth, emerge, come, follow, swell, head.

originate (verb)	well up (verb)
bring into being	come up (as of feelings and thoughts, or other ephemeral things)
come into existence; take on form or shape
begin a trip at a certain point, as of a plane, train, bus, etc.