You haven't got sharp driftwood in there have you, at least a piece that may be pointy enough to snag his nose if he has run into it, this can be common.. hopefully it heals up nicely, if not, I would put him in a seperate tank, nice clean water with a bit of salt.. and if you get to desperate measures then a bit of Melafix..
How is it looking now?
Geos and other cichlids etc can also be prone to Hole In The Head disease, and it can be more so common in Geos... from the pic it does look like an injury.. just a note on the Hole In The Head tho, often starts as a small open pore look.. and expands and goes deeper.. and often has a white fluffy piece in side, then when the fluffy piece falls out... you will see a crater... it's not normally the HITH that kills the fish, it's the bacterial infections etc than can set in... If nipped early enough fish can be treated with success, but often it can be a battle if a little too far gone.