spring up vs well up

spring up and well up both are verbs.

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

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

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

spring up (verb)	well up (verb)
come into existence; take on form or shape	come up (as of feelings and thoughts, or other ephemeral things)