Re: Query: Mars/Mountains

Glenn Morton (
Tue, 13 Aug 1996 22:10:14

Gene wrote:
>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?

I believe that was my post. I decided to resuscribe for a while.

The reference is Barrow and Tipler (the mad hatter), The Anthropic
Cosmological Principle, pp 307-309.

The reason Mars has a higher mountain is that the gravitational field on
Mars is less than Earth's. The theoretical maximum height of a Martian
mountain is, according to Barrow and the "Hatter" 8.8 x 10^-3 of the
planetary radius. This yields a theoretical height of 59 km. Olympus
mons is 25 km high.

I knowmof no theoretical limit to a trenches depth which has been
calculated. But there must be one. Pressure would tend to try to force
the trench closed.

Foundation,Fall and Flood