Maybe it is the "inlet" for feeding the Earths molten center. Just like anything else, you need a hole that stuff goes in if you have a hole that stuff comes out of.
Maybe it's the hole where the UFO's go! To their base deep inside the earths crust. How many UFO's are seen over the Atlantic? Isn't that where an entire flight of planes vanished years ago?
Hole could mean entrance tunnel!
Hey- it's as good a theory as any!