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Education Science

Ocean Floor Crust Wound to Be Explored 148

eldavojohn writes "A group of scientists are disembarking right now to study an open gash in the ocean floor where earth's mantle lays exposed without any crust covering it. The scientists describe this as the result of the mantle moving too quickly for the crust to keep up. Either that, or the mantle was never covered by the crust and just has always been like this. From the article, 'Regardless of how they formed, the exposed mantle provides scientists with a rare opportunity to study the Earth's rocky innards. Many attempts to drill deep into the planet barely get past the crust.'"
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Ocean Floor Crust Wound to Be Explored

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  • The earth has it's own goatse area
  • ohhh (Score:4, Funny)

    by Anonymous Coward on Sunday March 04, 2007 @04:46PM (#18229214)
    Nothing like a nice, wet, open gash down below to explore!

    I wonder what they'll find? Might be too deep for the little man in the boat.
  • Wake me (Score:4, Funny)

    by Anonymous Coward on Sunday March 04, 2007 @04:46PM (#18229220)
    Wake me when they get to the creamy nougat center.
  • One would have thought a volcano would form there, instead of it just staying in that exposed state.
    • by StarKruzr ( 74642 ) on Sunday March 04, 2007 @05:32PM (#18229646) Journal
      I don't understand how [water (cooling agent) + magma (what the mantle is made of] != crust evaluates to 1.
      • Re: (Score:1, Informative)

        by Anonymous Coward
        If i recall my school years correctly, the mantel is made of rock, not magma. In between the crust and mantle is the lithosphere (or whatever its called) that contains all the magma. I would assume that since crust hasent formed, there is no magma around there, which i would ask, why is that?
      • by Bellum Aeternus ( 891584 ) on Sunday March 04, 2007 @08:10PM (#18231578)
        You're right magma + coolant (water) = rock. The mantle is a section of the planet, comprised of different materials than the crust. This an opportunity to look at those materials without having to drill do far. Trust me, not many scientists was to be looking at 2000 degree molten rock up close.

        There's a lot of other cool things we can see while we're down there, like how the rock crystals formed under that kind of pressure and how fast they cooled. All kinds of cool things can be interpreted by the rocks crystalline structure.

        • How can rock THAT hot (rock closer to the core must necessarily be hotter than rock closer to the surface) NOT be magma? Pressure?
          • Re:Wait, what? (Score:5, Informative)

            by ElectricRook ( 264648 ) on Sunday March 04, 2007 @10:46PM (#18233004)
            Mantle rock is not magma. Mantle material is usually very hot because it is (A) very heavy, and (B) usually covered by a layer of insulating lighter crust material. The crust is 3-18 miles thick. Magma is usually crust material that got pushed down into hot mantle material and melted. The crustal material magma being lighter than mantle wants to rise above the mantle magma. So usually we have an intrusion of lighter crustal magma being forced through the mantle. So we've never seen mantle material exposed before. Some small samples of solid mantle material have been carried up by some of the cooler type volcanoes. This is how we get diamonds and peridots. Read about Kimberlite pipes.
            • (Apologies to Neal Stephenson)

              Thanks for the pointer, ElectricRook. I read all about Kimberlite Pipes [amnh.org] and now I'm excited by the prospect of "unearthing" a motherlode of diamonds on the sea floor! Perhaps these scientists have embarked, or disembarked, on that rare beast -- science with an immenent financial payoff.

              The Diamond Rush of 2010...
              • There are apparently diamonds almost everywhere, or some people think. Here in Northern California, they are reported to be found near where gold was discovered in Placerville California (Actually Smith Flat). I found what appears to be a kimberlite pipe in Northern Oregon. This is kind of a unique area, where volcanic islands were partially subducted and merged with the Coast. I don't know if diamonds will be found there, I've read they only appear in any meaningful quantities in about 2% of Kimberlite
                • You can get UV LEDs these days. Just swap the white LEDs in a flashlight with a bunch of UV ones. I'd also put a violet LED in there just as a reminder (I think they're white ones with filters, but anyway.)
                  • Yeah, but they don't have the proper band width. I did a bunch of work on this a year ago, and promptly forgot all about it.
                    • So you need to use lamps? I would have thought this problem would be solvable with some kind of phosphors (albeit at a reduced level of efficiency - but then, that's how white LEDs work anyway.)
                    • The real solution is X-rays, but UV light is the poor mans way.
                • by khallow ( 566160 )

                  I recall that small black diamonds were found in placer deposits in North Carolina. IIRC, supposedly the state of affairs then was that they didnt' even know if the diamonds were directly eroded from a kimberlite deposit or if they had subsequently been embeded in sedimentary rock and reeroded.

                  Good luck with that kimberlite pipe (and perhaps others like it). I figure any serious diamond deposits would have been discovered by now due to the extreme amount of gold panning that has gone on. However, as I rec

                  • All the gold in California lies in "A bank in middle of Beverly Hills in somebody else's name".

                    Oh wait back to the topic...

                    Most of the gold in California lies in "The Motherlode" mining district below 5,000' elevation between Downeyville, and Yosemite. It occupies just about all the streams in that region. Plus there is a north-south seam between Auburn and Jackson where we find the really deep hard rock mines (several thousand feet deep) There they mine gold bearing milky quartz in granite (only one min

                    • by khallow ( 566160 )

                      I have heard a theory that the gold was emitted by the mid oceanic ridge, and deposited on the sea floor. That sea floor was smashed onto the edge of California by accretion something like 250MYA (Million Years Ago). A lot if it was mixed into magma which intruded into the accreted crust as granite plumes, the gold being concentrated in quartz veins. The band being a portion of the sea floor that was not sub ducted, but instead acreted into the crust.

                      Assuming this is an accurate model, I'd bet that hydr

                    • It's apparently not a constant thing, but highly fluxuating, at one time 250MYA, it was a large quantity of gold, ocean floor measurements will tell what it is today. There is apparently a lot of mineral nodules on the abyssal planes.
                    • by khallow ( 566160 )
                      Maybe it's nothing but 250 million years ago was the end of the Permian Era and the time of the Great Dying. Might have been some weird ocean floor chemistry from that time. But gold isn't very soluable in water until the temperature gets to around 300 degrees celsius (IIRC). Minute amounts of gold in the bedrock dissolve and deposit where the temperature drops to below the soluable temperature. So it's a matter of local conditions (ie, there has to be some gold in the bedrock before it can dissolve and red
            • by Kiffer ( 206134 )
              I've yet to RTFA yet but, I've one or too points to make...
              You're statment "Magma is usually crust material that got pushed down into hot mantle material and melted." is not entirely accurate.

              In subduction zones where crustal material gets pulled down in to the mantle the melting is very often that of the mantle between the subducted and the subducting crustal slabs. The subducted slab carries a lot of water and as it heats the water is released in to the mantle, this changes the melting temperature of th
      • Re: (Score:1, Offtopic)

        by dwater ( 72834 )
        I think you'll find it evaluates to 'true'.

        I hate all this 0==false/otherwise==true crap. It makes for some really unreadable code. Is it really that much more effort to make a boolean var with a meaningful name? I expect a compiler would optimise it out easily...
        • Re: (Score:3, Funny)

          by TapeCutter ( 624760 )
          "It makes for some really unreadable code. Is it really that much more effort to make a boolean var with a meaningful name?"

          #define _SARCASM (~0)
          #include "sarcasm.h"

          boolean it_is_called_code_for_a_reason = true;
    • by dwarmstr ( 993558 ) on Sunday March 04, 2007 @06:58PM (#18230790) Homepage
      The mantle is a solid, albeit warm and plastic, material. It's solid because of the immense pressure the material is under. Brought up via plate tectonics, the material can melt as the pressure is released.

  • disembark? (Score:4, Informative)

    by mr_zorg ( 259994 ) on Sunday March 04, 2007 @04:47PM (#18229234)
    They are embarking, not disembarking...
    • by moonbender ( 547943 ) <moonbenderNO@SPAMgmail.com> on Sunday March 04, 2007 @04:58PM (#18229316)
      Inflammable means flammable? What a country!
    • Re: (Score:2, Funny)

      by Tablizer ( 95088 )
      They are embarking, not disembarking...

      So we're letting dogs sniff our crack, eh?
           
    • Re: (Score:2, Informative)

      They are disembarking from their port of origin, and embarking on a mission to study the ocean floor gash. The summary used the word correctly. s/disembarking/embarking/ without changing anything else in the summary would result in something that didn't make sense.
      • Re: (Score:1, Informative)

        by Anonymous Coward
        To disembark means to go ashore, you can't "disembark from [a port]".
      • Either that, or they've arrived, and they're going for an EVA. The post is just ambiguous.
      • >They are disembarking from their port of origin, and embarking on a mission to study the ocean floor gash.

        The first part of this sentence would make sense only if disembark meant to set out on a journey. It actually means to get off a barque which is a type of ship. It is frequently used loosely to mean to get off any ship or even any large conveyance. But it never means to set out on a journey.

        The second part of the sentence is probably correct since they will most certainly have to get on a ship in
        • Well, you're right that I'm wrong, but you're not right completely.

          The first part of this sentence would make sense only if disembark meant to set out on a journey.

          "They are disembarking from their port of origin." -> "They are setting out on a journey from their port of origin." Ok, that would work. But that isn't the false meaning of disembark I really had in mind. I was thinking more like (first sentence) -> "They are leaving their port of origin." This also works.

          The second part of the se

      • by Surt ( 22457 )
        http://209.161.33.50/dictionary/disembarking [209.161.33.50]
        (merriam webster online):

        disembark
        One entry found.

        disembark

        Main Entry:
        disembark Listen to the pronunciation of disembark
        Pronunciation:
        \dis-m-bärk\
        Function:
        verb
        Etymology:
        Middle French desembarquer, from des- dis- + embarquer to embark
        Date:
        1582

        transitive verb : to remove to shore from a ship intransitive verb 1 : to go
        • Yes, the summary is wrong, and I was wrong. However, it is still true that s/disembark/embark/ produces meaninglessness.
        • Re: (Score:1, Funny)

          by Anonymous Coward
          There is an inflated boat here.
          The magic boat contains:
          A tan label.

          >get tan label
          Taken.

          >read label
          !!!! FROBOZZ MAGIC BOAT COMPANY !!!!

          Hello, sailor!

          Instructions for use:

          To get into the boat, say 'BOARD'
          To leave the boat, say 'DISEMBARK'
          To get into a body of water, say 'LAUNCH'
          To get to shore, say 'LAND'

          Warranty:

          This boat i
      • Dang it! Mod me down, I'm wrong!
  • by Original Replica ( 908688 ) on Sunday March 04, 2007 @04:52PM (#18229278) Journal
    Imagine if this had formed on land, say in LA...
    • You say that as if it would've been a bad thing.
    • by dwater ( 72834 )
      I'd vote for DC.
    • If you want thin crust you really have to go to Boston's North End. I recommend thin crust with artichoke hearts and proscuitto.
    • Imagine if this had formed on land, say in LA...

      Cuz I'm praying for rain
      And I'm praying for tidal waves
      I wanna see the ground give way.
      I wanna watch it all go down.
      Mom please flush it all away.
      I wanna see it go right in and down.
      I wanna watch it go right in.
      Watch you flush it all away.

  • by ruiner13 ( 527499 ) on Sunday March 04, 2007 @04:52PM (#18229286) Homepage
    Hasn't the mid-atlantic ridge always been there? How is this a "rare opportunity"? I don't think it will be going anywhere anytime soon.
    • by Tablizer ( 95088 )
      Hasn't the mid-atlantic ridge always been there? How is this a "rare opportunity"? I don't think it will be going anywhere anytime soon.

      In B sci-fi, the portal *always* starts to close at an inopportune time. Thus, we gotta rush.
           
    • Re: (Score:2, Insightful)

      by Stormx2 ( 1003260 )
      The wording is pretty terrible:

      'Regardless of how they formed, the exposed mantle provides scientists with a rare opportunity to study the Earth's rocky innards. Many attempts to drill deep into the planet barely get past the crust.'


      Barely get past the crust? So they do get past the crust? Then how is exploring this bit of mantle different from exploring the parts we've drilled to?
      • by Mr2cents ( 323101 ) on Sunday March 04, 2007 @07:24PM (#18231064)
        A few months ago I was wondering how deep mankind has drilled, and found some interesting [damninteresting.com] stuff [wikipedia.org]. Basically, you should read "barely" as "didn't".

        As always, when you think something's easy (make_small_hole(); while(1) { make_hole_deeper(); } ), it's just because your ignorance doesn't let you appreciate the problems, like the extreme temperature and pressure. For example, I didn't realize that the pressure compresses the rocks and when you drill a hole that deep, the rocks around it want to expand, causing engineering nightmares.

        And while measuring the straightness of a hole seems quite doable (or put otherwise, I accept the assumption that there exists technology to do that), I still wonder how they can adjust the drilling direction.

        Fascinating!
        • If you read Robert Ballard's autobiography, or one of many other books on oceanography, you'll find that plate tectonics only started to become accepted as a credible theory in the 1960s, with many significant researchers still dismissing the theory in the early 1970s.

          To put that in context: people had visited the moon before plate tectonics was widely accepted.

          Since then there has been research, including drilling, but it is probably fair to say they mankind still only has a pretty fuzzy picture of what is

        • The shrinkage of the hole isn't the only problem and could partly be overcome by taking a larger drillhead than the drillshaft (or tube or whatever connection between the higher part and the drillhead).
          If you take a really long straw and place it vertically in your beverage, you can only lift the water so much before the weight of the water becomes higher than you could lift by sucking your mouth vacuum.
          This same effect happens with the rock deposit you drill up. You need to remove it to somewhere, and th
    • I think they mean "rare" as in there are not many PLACES you can find this. As opposed to there are not many TIMES you can find this.
    • Normally, even ocean ridges are covered by a thin layer of crust. What does come up is usually magma, which is not mantle material. http://en.wikipedia.org/wiki/Oceanic_ridge [wikipedia.org]
  • Analogy (Score:5, Informative)

    by Renfield Spiffioso ( 982789 ) on Sunday March 04, 2007 @04:56PM (#18229302)

    MacLeod likens this process to stretching a person's skin until it ruptures, exposing the flesh underneath.
    That's the most horrifying scientific analogy I've ever heard.
  • Anti-Crust (Score:4, Funny)

    by RancidMilk ( 872628 ) on Sunday March 04, 2007 @04:56PM (#18229304)
    If you tamper with the anti-crust, you will get burned.
  • by Anonymous Coward on Sunday March 04, 2007 @05:08PM (#18229406)
    Please do not anthropomorphize our planet. He really hates that.
  • Better close that hole up before the legions of nasty aquatic underworld ghoulies come pouring out into the world
    • by pla ( 258480 )
      Better close that hole up before the legions of nasty aquatic underworld ghoulies come pouring out into the world

      Nonono, you have it all wrong - this will let scientists discover the LifeStream, so we can finally start building Mako reactors.
  • by Anonymous Coward
    It's global warming!
  • Can't wait (Score:3, Funny)

    by Dunbal ( 464142 ) on Sunday March 04, 2007 @05:14PM (#18229452)
    Someone is going to use this as evidence of humans causing global warming in 5...4...3...2...
  • by Slippery Pete ( 941650 ) on Sunday March 04, 2007 @05:16PM (#18229476)
    "Many attempts to drill deep into the planet barely get past the crust." I wasn't aware of any drilling that has past the crust. The deepest I knew about was the Kola Borehole [wikipedia.org] which only reached 12,262 meters. I understand drilling the seafloor saves us time and depth but I wasn't away of anyone getting through the crust yet.
    • by Nefarious Wheel ( 628136 ) on Sunday March 04, 2007 @05:46PM (#18229820) Journal
      ...and the beginning of the Space Age. There was an attempt to drill past the crust to the mantle in a spot where the transition came up fairly close to the Earth's surface, called Project Mohole http://www.nas.edu/history/mohole/ [nas.edu]. This referred to the Mohorovicic Discontinuity, or "Mohole". The IGY was an early attempt at an international cooperative effort in Earth studies.

      The importance of this effort was underlined by the fact that Walt Kelly's "Pogo" sent it up. Since the event was a "year" of 18 months, Pogo suggested naming the extra months after foods -- Octoberry, Novemberry etc.

      In a side note, the US response to Sputnik included a science payload named Nora-Alice 1, beacon transmitter for Discoverer satellite, which took it's name from a poem Pogo wrote in honour of the IGY. http://www.ece.uiuc.edu/about/history/reminiscence /space.html/ [uiuc.edu] has a picture and a small quote down the column a bit.

      So as you can see, drilling a hole in the Earth past the crust to the mantle inspired some of the first orbital satellites. Remarkable! Oh, and then there was LAGEOS, of course, but I'll let you look that one up.

      • While my brother was in high school one of his classmates winged it during a class where they had to read their book reports. This guy made up a book called "The Moho Menace" where hostile creatures attack the surface after being released by drilling to the moho discontinuity.

        I only pray, for the sake of mankind, that it was fiction.
  • Hens lay eggs. They don't lay down.
  • "My God, it's full of lava!"

    --
    "How inappropriate to call this planet earth when it is quite clearly Ocean." - Arthur C. Clarke
  • These guys are hardcore!

    I mean, the last time I was invited to inspect an open wound in someone's gash, I ran.

  • Col. Robert Iverson: People. Doctors Zimsky and Keyes? You guys are our resident geophysicists, so what do you make of this?
    Dr. Conrad Zimsky: The mantle is a chemical hodgepodge of, a, variety of elements...
    Dr. Ed 'Braz' Brazzelton: Say it with me: "I don't know."
  • "MacLeod likens this process to stretching a persons skin until it ruptures, exposing the flesh underneath. You take the crust and you stretch it and you pull it and pull it until it breaks, he said."

    They found the goatse.cx guy.

    --
    BMO
  • by ZeroExistenZ ( 721849 ) on Sunday March 04, 2007 @08:33PM (#18231830)
    They'll just run away in fear [jesus-is-savior.com] like the commies did :P
  • This reminds me of a book I read recently by Robin Cook called "Abduction" - about a civilisation of humans (who evolved independently from surface humans) who live under the sea - a place they call "InterTerra".

    http://www.amazon.com/Abduction-Robin-Cook/dp/0425 17736X [amazon.com]

    Anyway, the plot is terribly contrived and the writing is bad, but it was strangely compelling and I just had to find out what happened at the end.

    So just be careful you don't go and piss off an advanced civilisation with your undersea drillin
  • A gash? Well, now really, can't they afford the old girl some privacy?
  • Ewwww... crust wound...
  • Now that we've penetrated the earth's crust, we just need to make sure we don't touch the ooze and turn green and hairy [bbc.co.uk]!

    Oh, come on, there've got to be some Doctor Who fans out there! ;-)
  • mmmmmmm Pie.
  • "It's only a crust wound."

    Matt Jeppsen
    FresHDV.com

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