interspersal vs interspersion

interspersal and interspersion both are nouns.

Word	Noun	Adjective	Verb	Adverb
interspersal	Yes	No	No	No
interspersion	Yes	No	No	No

As nouns, interspersal and interspersion are synonyms defined as:

interspersal and interspersion: the act of combining one thing at intervals among other things

interspersal (noun)	interspersion (noun)
the act of combining one thing at intervals among other things	the act of combining one thing at intervals among other things