by MarkBour » Sat Sep 01, 2018 4:56 am
Chris Peterson wrote: ↑Fri Aug 31, 2018 9:02 pm
Sa Ji Tario wrote: ↑Fri Aug 31, 2018 2:06 pm
I propose a logic game.-
Suppose we can bring the intact Earth to Mount Olympus (more than 24,000 meters high) and deposit it on the surface at sea level remembering that its base is about 600 km in diameter. It will begin then, a fight between the terrestrial gravity and the Martian density that when they were balanced would be a landscape different from the Martian and a new one in our planet. It will be a few hills of little more than 600 x 650 km and with maximum heights that would not exceed 4,000 meters. Earth's gravity would disintegrate and collapse the walls of Mount Olimpus and lateral plains and compress them until densifying them to the terrestrial tenor and always to my knowledge and understanding and subject to correction and discussion
I'm guessing you're considering what would happen if a structure like Olympus Mons were on Earth. In fact, I don't think it would be dynamically unstable. Of course, it would erode away over time, but rock is strong enough to support a cone 600 km in diameter and 24 km high without collapsing under its own weight on Earth. There are reasons, related to the strength of gravity, why such a structure might not be able to
form volcanically on Earth, but not why it couldn't exist if it were magically transported here. It might well collapse somewhat as the underlying continental crust deforms down into the mantle. The degree of collapse in that case would depend upon the thickness of that crust and the properties of the underlying mantle. And it would be slow- thousands or tens of thousands of years, at least.
I think you're right in interpreting the thought experiment that Sa Ji Tario was proposing. And I'm guessing that he/she is making a conjecture that Olympus Mons, since it formed under Mars gravity, will be made of basalt that is less dense than the basalt that forms on Earth under our larger gravity. Or perhaps that the walls would be steeper or thinner than would be formed on Earth.
If so, I don't know if any of those would be true. If you take a pool of lava and let it flow down the side of a mountain under Mars' gravity, would it really form anything that is less dense, or would it form structures that were otherwise different in profile than it would on Earth? Or would it form essentially the same structure? From what little I know, I would expect it to be pretty much the same on either planet. It may well be that Sa knows something about this that I do not.
[quote="Chris Peterson" post_id=285439 time=1535749338 user_id=117706]
[quote="Sa Ji Tario" post_id=285430 time=1535724387]
I propose a logic game.-
Suppose we can bring the intact Earth to Mount Olympus (more than 24,000 meters high) and deposit it on the surface at sea level remembering that its base is about 600 km in diameter. It will begin then, a fight between the terrestrial gravity and the Martian density that when they were balanced would be a landscape different from the Martian and a new one in our planet. It will be a few hills of little more than 600 x 650 km and with maximum heights that would not exceed 4,000 meters. Earth's gravity would disintegrate and collapse the walls of Mount Olimpus and lateral plains and compress them until densifying them to the terrestrial tenor and always to my knowledge and understanding and subject to correction and discussion
[/quote]
I'm guessing you're considering what would happen if a structure like Olympus Mons were on Earth. In fact, I don't think it would be dynamically unstable. Of course, it would erode away over time, but rock is strong enough to support a cone 600 km in diameter and 24 km high without collapsing under its own weight on Earth. There are reasons, related to the strength of gravity, why such a structure might not be able to [i]form [/i]volcanically on Earth, but not why it couldn't exist if it were magically transported here. It might well collapse somewhat as the underlying continental crust deforms down into the mantle. The degree of collapse in that case would depend upon the thickness of that crust and the properties of the underlying mantle. And it would be slow- thousands or tens of thousands of years, at least.
[/quote]
I think you're right in interpreting the thought experiment that Sa Ji Tario was proposing. And I'm guessing that he/she is making a conjecture that Olympus Mons, since it formed under Mars gravity, will be made of basalt that is less dense than the basalt that forms on Earth under our larger gravity. Or perhaps that the walls would be steeper or thinner than would be formed on Earth.
If so, I don't know if any of those would be true. If you take a pool of lava and let it flow down the side of a mountain under Mars' gravity, would it really form anything that is less dense, or would it form structures that were otherwise different in profile than it would on Earth? Or would it form essentially the same structure? From what little I know, I would expect it to be pretty much the same on either planet. It may well be that Sa knows something about this that I do not.