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Solving an Earth-Sized Jigsaw Puzzle

Posted by samzenpus on from the get-the-edges-first dept.

aarondubrow writes "Three years ago, researchers from Caltech and The University of Texas at Austin came together to create a computational tool that could model the Earth and answer the most pressing questions in geophysics: What controls the speed of plates? How do microplates interact? How much energy do the plates generate and how does it dissipate? Using a new geodynamics software package they developed, the researchers have modeled plate motion with greater accuracy than ever before. The project is also a finalist for the Gordon Bell Prize — high performance computing's Oscar — at this year's SC10 conference."

39 comments

  1. how is this measured? by molecular · · Score: 1

    The researchers are quick to point out that the project is not simply a computational success. “Models are important, but this isn’t just a modeling exercise,” Gurnis said. “The models are intimately coupled with observations, and validated as well.”

    Anyone know how the measure this stuff?

    1. Re:how is this measured? by thijsh · · Score: 0

      With an earth-sized measuring tape... Duhh.

    2. Re:how is this measured? by palndrumm · · Score: 5, Informative

      You can measure plate motions with GPS, if you're patient. Most of the deep structure is worked out using seismic imaging.

    3. Re:how is this measured? by terremoto · · Score: 5, Informative

      Anyone know how the measure this stuff?

      Short term (human lifetime) by using GPS, VLBI and measurements of seismic activity.

      Long term (earth lifetime) by using magnetic stripe lineations on the seafloor, hot-spot tracks (eg, the Hawaiian volcano chain) and other geologic indicators.

      http://en.wikipedia.org/wiki/Plate_reconstruction

    4. Re:how is this measured? by mlush · · Score: 4, Insightful

      You can measure plate motions with GPS, if you're patient. Most of the deep structure is worked out using seismic imaging.

      You don't have to be really patient... plates move at 2-10 cm/year so you'd start getting GPS data within 2-5 years, Historic data is not too hard to get as the Magnetic stripe patterns on the spreading seafloor give data going back to the Jurassic and the mechanical/geological fit between continents gives data on the original configuration

    5. Re:how is this measured? by digitig · · Score: 1

      You don't even have to be that patient. With a GPS fiducial network you could be getting results in months rather than years.

      --
      Quidnam Latine loqui modo coepi?
    6. Re:how is this measured? by Terje+Mathisen · · Score: 4, Informative

      GPS is the canonical answer here, but not in the form you use in your car or while hiking.

      Instead they use the same setup as a surveyor who measures a piece of land:

      You have one stationary receiver (the Base station) and one that you move around to measure (the Rover), while a radio link sends information from the base station to the rover.

      By observation of the same set of satellites from two points you can lock on to the 1.5 GHz (20 cm wave length) carrier wave, this gives you ~10mm or better resolution within a short time.

      For plate tectonics you do the same, but over significantly longer time periods to compensate for the much larger offsets between the two stations.

      Before GPS you could do similar stuff with radio telescopes observing pulsars (Very Long Baseline Interferometry), but you still need very carefully synchronized clocks at the two sites, and these days GPS is used for that (i.e. clock sync) as well!

      Terje

      --
      "almost all programming can be viewed as an exercise in caching"
    7. Re:how is this measured? by mlush · · Score: 2, Interesting

      You don't even have to be that patient. With a GPS fiducial network you could be getting results in months rather than years.

      Does this work in practice? As I understand it a GPS fiducial network uses ground bases transmitters which would move along with the plate which at the very least would complicate the data analysis...

    8. Re:how is this measured? by digitig · · Score: 1

      Well, you need a few receivers on the same plate, but by looking at phase differences you can even detect movement within the plate. See this for example. Sure, the calculations are complex, but there are plenty of folks who don't let that put them off.

      --
      Quidnam Latine loqui modo coepi?
    9. Re:how is this measured? by digitig · · Score: 3, Informative

      Sorry, I must have mistyped the html on the link.

      --
      Quidnam Latine loqui modo coepi?
    10. Re:how is this measured? by Anonymous Coward · · Score: 0

      "You don't have to be really patient... plates move at 2-10 cm/year so you'd start getting GPS data within 2-5 years"

      It's faster than that. A few days/weeks of monitoring with the right equipment is sufficient at a given station (these are *not* handheld GPS units!), allowing the motion of entire regions to be studied from many points in a year or two of fieldwork moving the stations around. And many regions now have permanently mounted GPS networks to monitor continuously. A couple of years of continuous data is sufficient to get great detail and precision. That allows geologists to study not only the motion of entire plates, but the details of deformation of mountain ranges at the plate boundaries and the effects of individual earthquakes -- essentially real-time monitoring of the motion of the Earth's surface at millimetre precision. Here are a few papers [PDF].

      If you want to know how fast you are moving at your own location with respect to a given reference frame try this, which is derived from current whole-Earth models of plate motion. Please note that it probably won't be accurate in areas with complex deformation near plate boundaries (it models the plates as rigid), but if you're within the plate somewhere it will be a reasonable approximation.

      One of the coolest analogies of scale ever: the plates move at about the same rate that your fingernails grow.

    11. Re:how is this measured? by Anonymous Coward · · Score: 0

      "Short term (human lifetime) by using GPS, VLBI and measurements of seismic activity."

      Also: laser satellite ranging, on both artificial and natural satellites (i.e. the reflectors installed on the Moon -- still useful!). In practice the VLBI and laser satellite ranging is used to establish a reliable global reference frame, and then GPS is tied to that, and used more extensively for mobile and permanent ground stations.

  2. SC10? by juletre · · Score: 0, Offtopic

    There is a StarCraft 10 ? Why I am still playing SC2 ?

    --
    "he, who has quotes in his signature, is a douche" - unknown.
  3. Why? by Psaakyrn · · Score: 1

    Is there any reason, if people will SILL live in California despite anything you can dig out?

    1. Re:Why? by MichaelSmith · · Score: 2, Insightful

      Is there any reason, if people will SILL live in California despite anything you can dig out?

      Setting aside parser errors I suppose California is only dangerous if you choose to live under an unstable pile of rocks.

      --
      http://michaelsmith.id.au
    2. Re:Why? by JasterBobaMereel · · Score: 4, Insightful

      A large proportion of the worlds population live in earthquake or volcano zones ... ...Because that is where all the richest soils, and mineral deposits are ...

      Most large cities are on the coast or on large rivers and so are prone to flooding, because they grew due to being a port

      Very few cities are founded where it is safe, instead they are founded where resources are, which also turn out to be dangerous ....

      People continue to live there because that's where the work is ...

      --
      Puteulanus fenestra mortis
  4. Hooray, they spelled "Caltech" correctly! by Anonymous Coward · · Score: 0

    ... for once. Thank you!

  5. No doubt it'll be as accurate... by Viol8 · · Score: 1

    ... as related simulations that model the weather day to day. ie it'll work alright for the first week the earth was created then the next 4 billion years in the simulation will go so far off track that by 2010 it'll be telling us that australia is at the north pole and hawaii has appeared in lake victoria.

    1. Re:No doubt it'll be as accurate... by Anonymous Coward · · Score: 0

      That's fine. A prediction 640 000 years in the future aught to be enough for anybody.

  6. Deep Thought by johosaphats · · Score: 1

    I thought Deep Thought already did this. The answer was 42.

  7. 42 what? by Joe+The+Dragon · · Score: 1

    42 what?

  8. Meanwhile, Steven Wright claims... by jbarr · · Score: 1

    "I have a map of the United States, life size. 1 mile equals 1 mile.

    It's a bitch to fold it."

    --
    My mom always said, "Jim, you're 1 in a million." Given the current population, there are 7000 of me. God help us all!
  9. amazing what people can do with FORTRAN these days by wagadog · · Score: 1

    lol

  10. Pirates? by Type44Q · · Score: 1

    ...a computational tool that could model the Earth and answer the most pressing questions in geophysics: What controls the speed of plates?

    My brain initially processed that as "What controls the speed of pirates?" and for very brief moment I was slightly confused...

    1. Re:Pirates? by balbord · · Score: 1

      Why confused? It's a valid question!!!! There has to exist such a mechanism!

      --
      "If I have been able to see so far, It is because I went out and bought a damn binoculars" - Ze da Esquina
  11. Please make accurate titles by Anonymous Coward · · Score: 0

    This story is not about solving an earth sized puzzle its about simulating geophysics.

    Please make accurate titles. Please do not waste my time.

  12. That's one reason why it's interesting by penguinchris · · Score: 2, Interesting

    These sorts of models are great because you run the model, and then see which parts of the earth don't fit in real life. You can then investigate that area more closely and either refine the model, or refine your understanding of that particular region.

    I'm a geologist and most of my undergrad and graduate studies were on tectonics. What they've got here is fantastic and will yield a lot of great new research and discoveries about plate interactions. It's basically an extension of what people have been doing for decades (modeling and comparing models to reality where possible), so the idea is really not new, but the implementation is fantastic.

    So at first it should be fairly clunky, and if you run the model as you suggest going through all of earth's history, yes it will be wrong. But if you take it step-by-step based on what's already understood about past tectonic plate positions (which is quite a lot), i.e. constraining the model, it should be able to show us all kinds of new things and ultimately a complete run-through should be possible that's very accurate. They will be able to continually refine it, of course, as new research comes out, and have a fairly complete model of plate evolution based on whatever the currently accepted progression is.

    1. Re:That's one reason why it's interesting by shoor · · Score: 1

      it should be able to show us all kinds of new things and ultimately a complete run-through should be possible

      I'm not sure what the previous poster meant by 'complete run through', but it's in response to a probably sarcastic post about how weather predictions lose accuracy rather quickly. The reasons have nothing to do with the accuracy of the model but with chaos theory, the 'butterfly' effect. Very slight perturbations, even things happening outside the model like cosmic rays or gravitational influences of other stars, will cause slight, random, perturbations that will cascade into major differences. Change one tiny little event like having a extra 10 pound meteor hit the moon a billion years ago for instance, and Australia could have ended up at the North Pole.

      --
      In theory, theory and practice are the same; in practice they're different. (Yogi Berra & A. Einstein)
  13. Now you're beginning to understand... by GameboyRMH · · Score: 2, Funny

    Ah now you've uncovered the truth about the Theory of Natural Earthquakes. The whole field of geophysics is running a big scam, made to funnel money into the earthquake prediction business, give politicians more power over how we construct our buildings, and assure these "scientists" get more grant money!

    Earthquakes are actually caused almost entirely by the weight of buildings placed on tectonic plates. It changes the friction between the plates, causing them to slip.

    Did you ever notice that whenever an earthquake happens, buildings are under construction? Coincidence? I think not. Do you think tsunamis happen because of eathquakes? An alternative theory is that ship wakes eventually grow into tsunamis, which then trigger earthquakes. There is a lot of controversy over this. Of course nature does play some role, but it's greatly overstated. The earthquake predictions made by these "scientists" are wildly inaccurate, and it's quite safe to ignore these warnings. Anyone with some common sense can understand this.

    Preparing for an earthquake will only damage the economy. Besides I'm sure in the future our descendants will find a way to go back in time and prevent earthquakes from happening, so it would be premature to take any action now. Don't let these doomsayers scare you.

    --
    "When information is power, privacy is freedom" - Jah-Wren Ryel
    1. Re:Now you're beginning to understand... by Anonymous Coward · · Score: 0

      C'mon, somebody debunk this crap or at least mod as troll.

  14. Re:amazing what people can do with FORTRAN these d by deapbluesea · · Score: 1

    The article says they invented quite a few new algorithms from a clean sheet, so I'm guessing that they actually used an extension of F77, soooooo, it's brand new!

    --
    Government is not reason; it is not eloquent; it is force. Like fire, it is a dangerous servant and a fearful master.
  15. Re:amazing what people can do with FORTRAN these d by cthulhu11 · · Score: 1

    Since it's a Gordon Bell prize, shouldn't it have to run on PDP-11's?

  16. Growing Earth by flowwolf · · Score: 1

    Will this once and for all debunk this theory?

    1. Re:Growing Earth by RockDoctor · · Score: 1

      I used to cross swords regularly with Expanding-Earth kooks, and creationists too, on sci.geo.geology ; they're as bad as each other, and both equally prone to deliberate errors of logic, selective quoting, dodging and denying questions, etc.
      It's often been said about creation-critters that "you can't reason a man out of a position which he didn't arrive at through reason." The same can be said perfectly well of EE'rs.

      Disgusting bunch of fucktards, both of them ; living arguments for retroactive birth control. Thermonuclear retroactive birth control, preferably out to relatives with quite a small proportion of shared genes. Not that I'm swimming in anyone else's gene pool, but I certainly wouldn't want to share a gene pool with such unpleasant hominins.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"