Well an explanation I'd just heard , was that the martians created a synthetic Merkaba at the time of Atlantis , and this is IT. That they screwed up and haven't been able to correct the error.
I'd always heard there was a huge crystal there, but it could be a little of both.
Some links to the Markaba explanation.

http://www.google.com/search?client=...UTF-8&oe=UTF-8