This may seem obvious to some I guess but I haven't seen it in any other posts but if someone has mentioned it kudos to you.
I have to also throw out that I thought of this from reading a post by BabyBrutha.
So, nothing groundbreaking here but I think the Temple resides on top of the volcano we have been hearing about all along and that is Smokey's home and that is why the "Special Ops Others" (Referring to the Temple people as they seem considerably more bad ass than the others formerly led by Ben) were so frantic to get the Temple sealed up and prevent HIM from entering.
My position is its the volcano that lies below but at the very least it seems the Temple was placed there, and guarded so heavily to block an entrance to something.
I have already thought how this can be chipped away at but all I will say that the reason they have to seal up the Temple now and not before has something to do with Jacob's death.