Very different watches. Sport vs. something that can straddle dress and casual, but not too dressy and not too casual.
I personally love the Deep Sea Chrono. Great size at 42mm--not too big to be silly, but big enough to be modern and fit a variety of medium to larger wrist sizes. The textured dial is very nice. The chrono pushers are crisp. At start, there was no evident seconds had jump on the piece I tried. And I LOVE that the chrono doesn't require screw down pushers and crown to maintain water resistance, making the chrono very usable. Both pieces have no date--major kudos to JLC for that wise decision.
The Geophysic is nice too, but I haven't seen one in person yet. For me, the dial may be too white--would have preferred eggshell, but perhaps that isn't true enough to the original. The technical improvements are to be appreciated. I think the size at 38.5 mm is good for this particular piece. Not as much wrist presence, but the size fits the watch well, just as the size of the Deep Sea Chrono fits it well.
If you like both, perhaps the main deciding factor should be whether both will be available on your preferred schedule. I would not be surprised if the Geophysic is soon sold out as it's a limited edition. The Deep Sea Chrono is not limited, but who knows how much longer it will be produced. If I new I was going to get both eventually, I'd hunt down the Geophysic first, then get the Deep Sea Chrono.
If I would only get one....now that's a much harder question.
Good luck,
John