I'd like to ask a question of the geology braintrust. A while ago there
was a very informative post, perhaps by Mr. Morton, on why mountains on
Earth cannot be higher than some height (perhaps 6 miles?). But these
conditions can't apply to Mars, which has Olympus Mons at 8 miles high or
thereabouts. How come Mars can have higher mountains? Does it have
something to do with the red planet having a solid core?
Also, is there any limit to how deep an ocean trench might be?