convulsion vs upheaval

convulsion and upheaval both are nouns.

Word	Noun	Adjective	Verb	Adverb
convulsion	Yes	No	No	No
upheaval	Yes	No	No	No

As nouns, convulsion and upheaval are synonyms defined as:

Other synonyms of convulsion include turmoil.

convulsion (noun)	upheaval (noun)
a physical disturbance such as an earthquake or upheaval	disturbance usually in protest
violent uncontrollable contractions of muscles	(geology) a rise of land to a higher elevation (as in the process of mountain building)
a sudden uncontrollable attack	a state of violent disturbance and disorder (as in politics or social conditions generally)
a violent disturbance	a violent disturbance