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Geologists Claim Earth May Be Softer Around The Middle Than Previously Thought 98

A new geological study is suggesting that what we know about the lower mantle of the Earth may have to be reevaluated. Since we are unable to actually sample the Earth at those depths, scientists rely on the use of seismic waves to study the lower reaches of the Earth. This new study suggests that material in the lower mantle has unusual characteristics that make sound move more slowly, suggesting a softer makeup than previously thought. "What's most important for seismology is the acoustic properties--the propagation of sound. We determined the elasticity of ferropericlase through the pressure-induced high-spin to low-spin transition. We did this by measuring the velocity of acoustic waves propagating in different directions in a single crystal of the material and found that over an extended pressure range (from about 395,000 to 590,000 atmospheres) the material became 'softer'--that is, the waves slowed down more than expected from previous work. Thus, at high temperature corresponding distributions will become very broad, which will result in a wide range of depth having subtly anomalous properties that perhaps extend through most of the lower mantle."
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Geologists Claim Earth May Be Softer Around The Middle Than Previously Thought

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  • by Lucas123 ( 935744 ) on Monday January 28, 2008 @02:11PM (#22210196) Homepage
    Jenny Craig. It worked for Pluto.
    • More to the point, does this impact "global warming?"

      Does this soft element transmit heat from the earth's core to the surface more easily than previously thought? Does that account for the change in temperatures? Is this a new phenomenon?
      • Re: (Score:3, Funny)

        by pilgrim23 ( 716938 )
        BAH! and you call yourself Scientists! Global Warming only happens to keep the Earth Egg properly nurtured until it cracks open vomiting the spawn of the Old Ones into the chaos. Don't worry though; it will only happen when the middle of the Earth starts thinning measurably and... oh dear...
    • I blame America, home of the Big Mac and Whopper.
    • by pugugly ( 152978 )
      Mmmmmm - I just love it when the soft gooey center is just right. Dip it in a red giant, and just nibble it . . .

  • by Anonymous Coward
    Makes sense - it gets older - it gets fatter - softer in the middle :-)
  • And chewy too!
  • Well duh! (Score:4, Funny)

    by Brandybuck ( 704397 ) on Monday January 28, 2008 @02:15PM (#22210248) Homepage Journal
    Well duh! As I get older I get softer around the middle too!
    • Nice one.

      When I first glanced at the headline I thought it said

      Geologists May Be Softer Around The Middle Than Previously Thought

      I may have to harangue some of the boys down the hall on this one...
  • by butterwise ( 862336 ) <butterwise AT gmail> on Monday January 28, 2008 @02:15PM (#22210252)
    Softer around the middle, thinning ice sheets - sounds like somebody's getting older...
  • Earth! (Score:3, Funny)

    by Daishiman ( 698845 ) on Monday January 28, 2008 @02:15PM (#22210256)
    Now with delicious soft filling and an irresistably crunchy core!
    • Obviously you didn't RTFA, just the headline!

      Geologists Claim Earth May Be Softer Around The Middle Than Previously Thought.

      AP - Reports of nougat center, still unconfirmed. Scientists say, "More study and milk required."
    • Now I understand what Galactus saw in eating earth. :)
  • So is that why our nights are so long?

    More on topic, I wonder what difference this will make to the study of seismology? Don't different densities refract the pressure waves from seismic events? Perhaps this new model will improve the ability to measure the location of earthquakes?
  • Jawbreaker (Score:3, Funny)

    by 4D6963 ( 933028 ) on Monday January 28, 2008 @02:18PM (#22210290)

    I said it before and I'll say it again, the Earth is a giant micro-waved jawbreaker [], and it's warming up! Y'all laughed at me, just wait until you get licked to death by the giant tongue from outer space, or burnt to death once it explodes.

  • I get softer in the middle the more I sit at my desk and surf /. at work.
  • Welcome (Score:4, Funny)

    by Capt James McCarthy ( 860294 ) on Monday January 28, 2008 @02:26PM (#22210402) Journal
    To middle-age, Earth. Wait until things begin to get saggy and noisy all over.
  • Perhaps everything slows down because at its core the Earth is just stupid.
  • by RipTides9x ( 804495 ) on Monday January 28, 2008 @02:33PM (#22210490) Journal
    The Russians made 6.7km before giving up drilling not only because of the heat (180c), which could have been worked around, but mainly because any further drilling beyond that point the hole had a tendency to close up like molten soft plastic upon retraction of the drill bit. []
    • Re: (Score:2, Interesting)

      by RipTides9x ( 804495 )
      Damn I stepped on my dick, they made 12Km before calling it quits, 6.7Km is the depth they were finding fossils where they didn't expect it.
      • Damn I stepped on my dick, they made 12Km

        You mean you replied to all the spam, and it worked?

      • by trongey ( 21550 )

        Damn I stepped on my dick...

        Without pictures, it didn't happen.
      • Damn I stepped on my dick, they made 12Km before calling it quits, 6.7Km is the depth they were finding fossils where they didn't expect it.

        Could you point me at the original reports of them finding fossils at any depth in the Kola super-deep borehole/ ANY fossils. ANY depth. I'm not particularly bothered if the reports are in the original Russian, or translated into English (or French for that matter).

        I'll give you a hint - I read some of the original reports myself when I was studying high-P metamorphism

    • by sconeu ( 64226 )
      Cool article.

      Just one question... I know that Libraries of Congress is a unit of information, and Volkswagons are units of mass. When did Abe Vigoda become a unit of age?
    • Well, duh. Teconic Enginnering is a pretty advanced tech field so it's obvious that we don't have Core Waste Dumps and/or Deep Core Mining yet. Given the fact that neither do we have developed Artificial Planets nor do we have contact with any other intelligent species yet, there's no way for us to have access to that stuff. I mean, we don't even have a Nuclear Drive yet.

      If/when the Antarans show up we're going to be so screwed...
      • Remember that the size of their fleet is based on the current level of technology in the galaxy. So even if we got attacked, it would just be by a single frigate - can't kill more than a few million & blow up a few factories.
  • We're all softer around the middle than we would like to think.
  • I wonder whether this observation gives any more credibility to the theory that the center of the Earth might have a nuclear reactor. The following article describes the theory: []
    • Go Aquabats! (Score:3, Informative)

      by techpawn ( 969834 )
      There is a chipmunk
      At the center of the earth
      And in his big oven
      He bakes his own desserts
      He warms the ocean
      And from that, life springs forth
      Little organisms building trash around the clock

      Compost heaps
      Or melting pots
      For Farmer John's
      Smoked Sausage stocks

      Worms make the dirt
      And the dirt makes the earth
      And all of the roots have a place to sleep now
      All the chanuks have squash to eat now
      Worms make the dirt
      And the dirt makes the earth
      And people hold hands and feel terrific
      Food comes from dirt
    • Interesting article, thanks. And it was nice of the paper to discuss the Oklo [] phenomenon. As far as the area around the earth's core being a nuclear reactor in the sense of maintaining a critical mass and critical geometry, I think that, at best the criticality is transient and unstable, going from subcritical to supercritical and vice-versa, given the dynamic nature of the fluid.

      Another fascinating observation from the paper is the dominance of the U235/U238 ratios, and how U235 (the fissile isotope)
  • Well, the Earth's primary intelligence (humans) is going soft in the head, so I guess it's just old age.
  • Everybody knows that the earth is really hollow and is filled with Reptilians who were banished there for being mean. Just wait til these goofy scientists find a way into it in 2012. Then we will all be doomed.

    Until then, I will keep wearing my tinfoil hat with pride.
  • There has been an error in the reporting
    Apparently the Geologists recently upgraded (read downgraded) their computers to Windows Vista
    Upon processing the results, the OS sensed they didnt not have a full license, and there for sent back only what they had paid for, leading to the premature conclusion of a softer core
  • that I got out of Geology as a career. I mean talk about boring.......
  • That makes sense, the Earth is only 6000 years old.. which is equivalent to 60 man years.
    At age 7000 the Earth will start spewing noxious fumes and it will need a giant catheter to pipe all fluids to outer space.
    At age 8000 it will become extremely wobbly, driving off from it's orbit.. some biblical historians also speculate it might smash into mars at this time..
    At 9000 light will become extremely dim and the Earth will only see daylight for 2 hrs in a day, the rotation and revolution speeds will slow d
  • Clearly we do not understand the properties of our inner earth as well as we would like. Where or how does physics describe this acoustic 'softness' given the circumstances? What of earths gravity? Does gravity truly intensify the closer towards to the center you are? Are there any mathematics that accurately describes all this? Lastly, how does the movement of the earth's magnetic dynamo play into all this. I'm no expert in physics, but I certainly hope we see answers to these questions in time.
    • by maraist ( 68387 ) *
      Gravity is zero at the center of any spheroid, either solid or hollow (because you have an equal amount of mass pulling you in every direction. The only difference between hollow and solid spheres, is that in a solid spheroid, you have the pressure of the density of the medium. In the case of earth, it would be like being really deep in the Ocean, but obviously much worse (you should have seen enough horror movies to figure out what happens there). If, instead you were able to somehow produce a tunnel th
  • NASA scientists are pumped because now they can just use a large ground pounding machine to effectively stop the birth of a smaller, more annoying baby Earth.
  • I can imagine that earth's "core" may be soft. My reasoning tells me that the "core" is not subject to much gravity. A micro-gravity environment, if you will, due to the relative equal mass in all directions pulling in all directions that balance. Once I think that, I have trouble wrapping my brain around the question: "How great is the pressure?"

    If the answer is (relatively speaking) low pressure, then with the estimated high temperature I can imagine a liquid like center.
    • The "core" is not subject to much gravity - relative equal mass in all directions pulling in all directions that balance.

      Damn, you beat me to it! That's exactly what I've been toying with for some time now, with an additional question: The densest materials fall to the bottom of the gravity well... and where exactly is that? Or put in another way - do the densest materials fall to a point of zero gravity?

      Of course, if you shift the liquefied iron or lead to, say the right, there's gonna be more of the Ea
    • If all the mass is attracting all the other mass, then the center will have the highest pressure, even if the local gravity is balanced. Remember, in the center you have this big spherical mass all around that is self-attracting. So the mass at the "left" is attracting that on the "right" and the "top" and "bottom" are interacting with both. So the only thing that stops them from pulling together is your matter in the center which must exert an equal and opposite resistance to compression force.

      Just beca
  • At the center of the earth is a singularity.

    Hell, it'd explain the red-shift and why no one can travel faster than the speed of light. ;^)

  • I've been saying this for years! Those sissy elves made Middle-Earth too soft! Their overly-peaceful ways made Sauron's rise to power almost inevitable!

    Oh, wait...

  • A softer than expected inner layer was the base of the crustal shifting theory of Charles Hapgood in his Path of the Pole [] book.

    The book and theories were prefaced/backed by Einstein, but it was rejected by geologists.

    Maybe there was a seed of truth in Hapgood's work?

  • funny, what we don't know, there is a giant city of crazy rock people who live down there, they are related to rosie od'nal, and Carlos mencia

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