Dear Keiva, belMarduk and wwh:

Keiva
Yes, your example is more palatable. The book offered this serving...think of the ice as a thick pancake batter that you are pouring on a griddle. Now drop a blueberry on top of the batter...
wwh
Yes, I thought the same thing. But the example of a six-foot annual accumulation rate given by the book was poorly stated. In other words it was indeterminable as to whether it was Glacier Girl specific. I would think that a reasonable snow accumulation in places in Greenland could easily be double that.
belMarduk
Yes bel, I wondered about that myself. Caves are voids within limestone under great pressures but not enough to make the rock plastic. I bet that if the airplane was air filled (no pun) it would have a better chance of exiting intact than it would if it was filled with ice.
Stales
Whew...stales where are you?