Replying as a temporary cutoff, pending comms with everyone who's commented above and messaged me. So, I was not expecting that much traffic that quickly... glad I checked back!
They really don't like to be updated over minor errors in essays. If the word missing makes your essay unreadable, I guess it makes sense to send in an update. If they can understand what your essay is getting at with the typo, I would not email them.
... geologically quiet regions only contain minor faults. Since there are only ... minor faults in the region, it' ... the stimulus saying that only minor faults exist in the region ... region that don't have minor faults would have an even ...