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Plant Sciences, Zoology & Evolution / Re: Can life exist beyond the deepest point in the ocean?
« on: 12/11/2020 18:51:08 »This seems to be asserting two things which appear opposites.
Having large empty spaces beneath the deepest part of the ocean seems unlikely to me - it would collapse (fill with rock) or at least fill with water.
They are not opposites as cavern and deep sea trenches exist. A completely smooth inner planet is just as unlikely as a completely smooth surface area. A cavern may exist at a hundred meter's in size, a maximum may very yet be one thousand meter's in size.
As to the comment about them collapsing that can't be assumed because of several factors.
- Earths gravity comes from the core of the planet, therefore if an object has less of earths' gravity applied to it the further away you get then a object by extension would have more gravity applied to it the closer to the core you get.
- The rock have a higher density and are able to sustain significantly higher surface tension and pressure before a crack emerges. Even more so than that if a highly dense rock is damaged it is more likely to have a smaller chunk break away rather then a full collapse.
- Given than foundational support is a significant factor as to why thing's built high would collapse in the first place solely based on gravity then being so deep underground offers the position that surface cavern system simply do not have. The rock surrounding said cavern is just as dense as the rock making up the cavern because they are the same rock just in different layers.
Seeing as how structures tend to hold together much better when surrounded with support it can be assumed cavern systems would react in a similar way. Though I will admit details and any definitive statement is only left to speculation simply because the research hasn't been done on anything really past the crust of the planet.
However, it is thought that this impact of a Mars-sized object with the early Earth would have released so much energy that it would have melted the surface of the Earth, effectively sterilizing any life that was there previously.
Only on the surface of the planet, however what I said was it could have opened a pathway. That was literal, it could have fractured a cavern system of split the ocean bed enough for life to come from it, that could have then closed over hundreds of millions of years due to gravitational pressure. Said organisms could have simply just evolved to live in their new environments slowing moving up more and more until they became what is know as the first land based organisms.