100 feet down again. I have a theory I thought of a couple of days ago that if there was a crustal displcement and it caused the North Pole to be replaced by a sea istead of dry land that this would cause more of the earth's water to avoid being trapped as ice. In other words move North America up a little and Antarctica over a little and you have two land masses on each pole able to hold a lot more ice than now since presently there isn't any land at the North pole.
That may also explain quick-frozen Siberian mammoths who died and were frozen standing up also. Our poles flip every so often, South to North and vice-versa. Scientists say that when lave flows out of a volcano that it "grains" according to the magnetic field. That tells me that there is a force in the crust of the earth wherever there is lava solidified (which is most of the earth) that will try to align with the poles of the earth's core like a compass needle. If the earth's crust were molten, then each individual molecule would simply turn with a pole switch where it sits, being able to slide against each other in a liquid state. But since the earth's crust is solid there will be an integrated force that will attempt to move the whole crust and being that the crust sits on a liquid mantle, it may be able to do that.
Something I thought of two days ago when I woke up. That's when I do my best thinking. :^)