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Inspired by the movie, "The Core".

Can we really travel through earth's core? I will provide 2 sub questions:

  1. Is there any substance that can resist the heat of earth's core?

  2. Between the crust and mantle, and the mantle and outer core is there any "wall" between them? And how hard is the wall (can we go through it)?

Gimelist
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Poomrokc The 3years
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    Short answer: No. On the large scale you can think of the Earth as a big ball of fluid. Withstanding the pressure of the bottom of the ocean is something that we are barely able to do, and that is only 0.2% of the way to the center of the Earth. – Chris Mueller Apr 17 '14 at 02:15
  • @ChrisMueller You mean that there is some(0.2%) Hole open for us to pass through? – Poomrokc The 3years Apr 17 '14 at 02:17
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    No, I am saying that the pressure increases with depth as you go down into the Earth (in the oceans or in the crust). Right now we have a hard time withstanding the pressure at a depth of 11 km, but the depth of the Earth is 6400 km. So, there is no way we can send a submarine like vessel to the center of the Earth right now. – Chris Mueller Apr 17 '14 at 02:21
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    This question currently has 7 upvotes and 7 downvotes. Possibly we need to discuss it on Meta? ;-) – Semidiurnal Simon Nov 07 '14 at 11:48
  • Meta question here: http://meta.earthscience.stackexchange.com/questions/343/should-we-discourage-wildly-hypothetical-questions/344#344 – Semidiurnal Simon Nov 07 '14 at 11:53
  • related: http://earthscience.stackexchange.com/q/2468/725 – Gimelist Nov 29 '14 at 11:31
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    Also note that the Core has been voted to be the worst sciency movie of all time. By action as well as by scientific content. So don't take it too seriously. – AtmosphericPrisonEscape Mar 09 '17 at 16:30

4 Answers4

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As Chris Mueller said, in short: it isn't, or at least highly infeasible. Projects to drill into the mantle, such as the Kola Superdeep Borehole, have all failed because drilling equipment can't withstand the heat at only ~15km deep. Even if we were to come up with some sort of cooling system that's able to cool to 6400km or 12800km deep (depending on whether you would drill from one side only or from both sides at the same time), pressure is the second barrier that holds us from traveling through the earth's core.

According to Lide (2006) the pressure in the inner core is 330 to 360 GPa, at which iron becomes a solid even at the high temperatures in the core. If you could drill as far as the core you would have to build a device that's able to withstand that pressure, because if you can't, the material surrounding your well would immediately become liquid and fill the hole, if not shoot up your well towards the surface.

There are no physical walls between the layers of the Earth, only transition zones where temperature and pressure combinations lead to different behaviour of the materials. An example is the Mohorovičić discontinuity, or Moho, which is the boundary between crust and mantle, below which temperatures are high enough and at the same time the pressure is low enough so that rock becomes either liquid or at least a "flowing" solid. Similarly, at the boundary between the inner and outer core the pressure is so high that even at those temperatures the iron becomes a solid.

Lide, D.R., ed. (2006-2007). CRC Handbook of Chemistry and Physics (87th ed.). pp. j14–13.

hugovdberg
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Short answer: No.

Long answer: Our deepest drills failed around 12km down when the drill bits were having to cope with temperatures hot enough to melt the drills.

12km down is only a tiny distance into the earth. The average distance to the center is over 6300km. So didn't even get to half of a percent of the way to the center.

To do so, we'd have to have:

  • a vehicle capable of propulsion through liquid magma
  • capable of drilling through various types of very thick rock
  • capable of surviving temperatures over 5400 degrees Celsius
  • capable of surviving pressures of over 330 gigapascals
  • capable of insulating passengers and their atmosphere within the vehicle from the extreme temperatures outside
  • capable of doing this in a reasonable time (ie days - given you'd need oxygen and food and water for the passengers)

none of which are currently possible.

Mark Mayo
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    I'm not certain about your first point. Molten rock in the deep earth is the exception, not the rule. – Gimelist Nov 06 '14 at 14:03
  • Sure, but they have to get through the surface stuff first, and it'd be kinda frustrating not to plan for that and then strike a pocket of it on the way down :/ – Mark Mayo Nov 06 '14 at 22:12
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    We have a pretty good idea of where there is melt and where there isn't melt. You can just plan your vehicle to drill through solid instead of both solid and liquid, and then just plan your route so it will not pass any liquids (or at least hope for the best). – Gimelist Nov 07 '14 at 07:48
  • If it can handle the heat of molten iron why would molten rock cause problems? In fact, molten rock is likely GOOD because it reduces the need to drill through solid materials. – Kevin Kostlan Jul 01 '17 at 22:29
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There is one vaguely plausible method that has been proposed: blow open a crack in the Earth's crust using a hydrogen bomb and then fill the crack with molten iron. The iron then sinks to the core, and a small probe can sit on top of it and ride it all the way down. There's no way to get it back again, of course, but it could transmit its data back to the surface using seismic waves. (We have detectors sensitive enough to pick them up.)

Although it's a pretty crazy idea, it was published in Nature magazine by a respected geophysicist, so there's a certain plausibility to it, although I don't think anyone intends to carry the plan out in practice. (Original article: Mission to Earth's core — a modest proposal, unfortunately paywalled. Googling the title will give a number of press articles about the idea.)

N. Virgo
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  • I love this idea , I would love to have you go to the earth's core with me by this method. Xp – Poomrokc The 3years Apr 23 '14 at 12:13
  • I'd rather stay here on the surface if it's ok with you :) one of the drawbacks of this idea is that there's no way to get back again. – N. Virgo Apr 23 '14 at 12:30
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    "The iron then sinks to the core" - no it will not. At least not in our lifetimes. – Gimelist Nov 06 '14 at 11:14
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    @Michael please take that up with the author of the original paper. It was published in Nature by a highly respected geophysicist though, so I'd tend to assume it has actually been quite well thought through. – N. Virgo Nov 06 '14 at 13:45
  • Where's the reference? First of all, blowing up the crust will not crack it, but just make a crater. The molten iron will indeed sink, but it will take a really long time for it to sink. Think about the timescales of rocks that sink, let's say in subduction zones. I suspect that the iron will solidify before it advances any significant distance. You have to remember that the crust is part of the lithosphere, which is rather rigid. – Gimelist Nov 06 '14 at 13:50
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    @Michael I've edited the reference (unfortunately paywalled) into the answer. Whether it makes a crack or a crater depends on the local geology, and how deep the explosion is. (We're not talking about a small bomb.) The idea is that it sinks rapidly because the crack is propagating due to the weight of iron splitting the lithosphere apart as it falls. (We're not talking about a small amount of iron.) It's a rapid process, not something that happens on normal geological timescales. – N. Virgo Nov 06 '14 at 13:55
  • Fortunately I have institutional access. So I've read the article. I'm not geophysicist, but he is talking about a self propagating crack in the lithosphere. What about the asthenosphere or the lower mantle where there are no cracks? And I've yet to understand how can you create a crack in the lithosphere using explosives (no matter how powerful they are). Again, think meteorite impacts. They make a crater, not a crack. – Gimelist Nov 06 '14 at 14:02
  • Also, you might be interested in this: http://link.springer.com/article/10.1007/s10512-005-0246-y – Gimelist Nov 06 '14 at 14:05
  • @Michael I'm no geophysicist either, but the ones I know seem to treat this idea as a plausible fantasy- it'll never happen, but they'd like it a lot if it did. I think meteorites make craters because they hit the surface. If an explosion is deep underground it can't eject stuff up into the air so it's more likely the energy goes into making a crack. That's my guess anyway- it's not my field but since it's published in Nature and hasn't been debunked I err on the side of believing it – N. Virgo Nov 06 '14 at 23:33
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Nuclear reactions would be required to create a shaft. High melting point solids under the extreme pressures would be required to reinforce it. If gamma rays can tunnel, the theory is not implausible but requires an engineering feet to put physics into practice. This should be the focus of exploration besides space exploration.

Paul
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  • This is just fanciful speculation. Please provide some substance to your answer. – bon Mar 09 '17 at 08:25