As I understand it enrichment is by gas centrifuge or thermal diffusion. An earthquake bomb would disrupt both. You wouldn't be starting the feed cycle up rapidly, but since we're told Iran has stockpiles, this goes to sustainable delivery of materials more than specific short term risk.
As a strategy, I see this as flawed. A dirty bomb remains viable with partially enriched materials.
(This does not mean to imply I support either bombing or production of weapons grade materiel. It's a comment to outcome, not wisdom)
