common fault vs gravity fault

common fault and gravity fault both are nouns.

Word	Noun	Adjective	Verb	Adverb
common fault	Yes	No	No	No
gravity fault	Yes	No	No	No

As nouns, common fault and gravity fault are synonyms defined as:

common fault and gravity fault: an inclined fault in which the hanging wall appears to have slipped downward relative to the footwall

Other synonyms of common fault include normal fault.

common fault (noun)	gravity fault (noun)
an inclined fault in which the hanging wall appears to have slipped downward relative to the footwall	an inclined fault in which the hanging wall appears to have slipped downward relative to the footwall