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Confirmed: Earth's Oldest Rock In Australia

SpamSlapper writes "Australia's ABC Science reports that ancient zircon crystals discovered in Western Australia have been positively dated to 4.374 billion years, confirming their place as the oldest rock ever found on Earth, according to a new study. The research reported in the journal Nature Geoscience, means Earth began forming a crust far sooner than previously thought, following the giant impact event which created the Earth-Moon system 4.5 billion years ago."

74 comments

  1. It comes from a land down under.. by jamesjw · · Score: 4, Funny

    Where this rock is about as old as the social and development views of our current Prime Minister..

    --
    -- If at first you don't succeed, lie!
    1. Re:It comes from a land down under.. by TapeCutter · · Score: 1

      It's a shinny rock! We dug it up! - Surprised Tony isn't trying to sell it to someone.

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    2. Re:It comes from a land down under.. by GloomE · · Score: 2, Funny

      Why would he? He knows it can't be more than 10,000 years old. These "scientists" don't know what they're talking about.

    3. Re:It comes from a land down under.. by Anonymous Coward · · Score: 0

      We didn't dig it up, the foreign mining companies did. They do own it, after all

    4. Re:It comes from a land down under.. by thePowersGang · · Score: 1

      I would like to defend this rock and state that it is nowhere near as old as our PM's views. (posting to undo bad moderation)

    5. Re:It comes from a land down under.. by Anonymous Coward · · Score: 0

      Don't you mean 6,000?

    6. Re:It comes from a land down under.. by GloomE · · Score: 1

      Your mathematicians also don't know what they are talking about.

    7. Re:It comes from a land down under.. by mjwx · · Score: 4, Insightful

      Where this rock is about as old as the social and development views of our current Prime Minister..

      However unlike Tony Abbott, the rock is worth something to Australia.

      --
      Calling someone a "hater" only means you can not rationally rebut their argument.
    8. Re: It comes from a land down under.. by Anonymous Coward · · Score: 0

      As far as I've understood there is little math involved at all.

    9. Re:It comes from a land down under.. by Jason+Levine · · Score: 1

      Bah! It can't be older than last Tuesday - when the world was created. Any memories you have of the time prior to last Tuesday were merely planted there as a test of your faith.

      --
      My sci-fi novel, Ghost Thief, is now available from Amazon.com.
    10. Re:It comes from a land down under.. by Anonymous Coward · · Score: 0

      It was last *Thursday*!

      Kill the heretic!

    11. Re: It comes from a land down under.. by GloomE · · Score: 0

      There's at least the bit where you set pi = 3.

    12. Re:It comes from a land down under.. by Anonymous Coward · · Score: 0

      I know he was mentioned in a mediaeval manuscript but that doesn't make him 4Ga old.

  2. Sounds about right... by Anonymous Coward · · Score: 0

    In the famous words of my old IT teacher: "Perth is that the place where they just invented shoes?".

    God I miss those days.

  3. Imma hit you so hard by Bite+The+Pillow · · Score: 1

    Imma hit you so hard, you gonna get a crust.

    And, I'm gonna kick your ass into ORBIT around you, SON!

    Now what?

  4. Citation of a hypothesis: by Anonymous Coward · · Score: 0

    The Giant Impact Hypothesis has never been confirmed. It's presented as fact here.

    1. Re:Citation of a hypothesis: by Anonymous Coward · · Score: 1

      It's what happens when you leave science reporting to journalism majors. Reading the abstract to the original Nature Geoscience article is more enlightening.

      One of the reasons people get so worked up about this mineral grain is because the oxygen isotope data says it formed when earth had oceans. If it's the age they think it is, it puts the development of oceans much earlier than they previously had evidence for. That would then support the impact hypothesis.

    2. Re:Citation of a hypothesis: by Anonymous Coward · · Score: 0

      It's what happens when you leave science reporting to journalism majors. Reading the abstract to the original Nature Geoscience article is more enlightening.

      One of the reasons people get so worked up about this mineral grain is because the oxygen isotope data says it formed when earth had oceans. If it's the age they think it is, it puts the development of oceans much earlier than they previously had evidence for. That would then support the impact hypothesis.

      First, what makes you think incompetence in reporting is limited to science?

      And how would oceans forming early be evidence the moon was formed from a giant impact?

  5. Ken Ham issues statement by Brad1138 · · Score: 2, Funny

    "there's this book..."

    --
    If you could reason with religious people, there would be no religious people
    1. Re:Ken Ham issues statement by cascadingstylesheet · · Score: 2

      "there's this book..."

      You don't have to be a creationist to have doubts about this kind of dating.

      It's pretty much the poster child of something that can't be confirmed by experiment.

    2. Re:Ken Ham issues statement by Improv · · Score: 1

      How do you think these dating methods came to be devised and then trusted by the scientific community?

      --
      For every problem, there is at least one solution that is simple, neat, and wrong.
    3. Re:Ken Ham issues statement by Anonymous Coward · · Score: 0

      Of course it can be confirmed by experiment, run the dating test on a rock in your back yard which will have an age of X years then wait 4.5 billion - X years and test again, just because it's not easy doesn't mean it can't be confirmed.

    4. Re:Ken Ham issues statement by Mashdar · · Score: 3, Informative

      I think gp's problem is with this specific type (U-Pb) of dating.
      I don't understand how initial values are determined. (Is there some method by which the original ratio of the two elements is known? Or the proportion of radioactive isotopes?)

      But, from the wikipedia article

      Uranium-lead (U-Pb) dating is one of the oldest[1] and most refined of the radiometric dating schemes, with a routine age range of about 1 million years to over 4.5 billion years, and with routine precisions in the 0.1-1 percent range.[2]

      so it does not sound at all un-tested.

      While GP is correct that we cannot experimentally confirm the specific mechanisms here (radioactive Pb decay over one million+ years...) , we have a very good description of radioactive decay across the board (table?) and observational results sound extremely consistent. Direct experimentation is not the only form of scientific evidence, despite what [creationist intelligent_designist whatever_nut] might say.

    5. Re:Ken Ham issues statement by Mashdar · · Score: 1

      Which reminds me -- My partner's brother was reemed by a clueless judge/history teacher at his middle school science fair for not having a control group in his observational study of moss growth across local tree species.... Observational study is awesome, especially when all you care about is correlation between a known and an unknown, rather than causailty. The US school system likes the word "experiment" too much for its own good.

    6. Re:Ken Ham issues statement by Anonymous Coward · · Score: 0

      then trusted by the scientific community?

      Dont confuse "trusted" with "its the best we can do".

      A friends wife is an archeologist and she openly admits that its very easy to contaminate the samples and the margin for error is questionable, but there are no other reasonable alternatives. I dont know if thats your definition of "trusted".

    7. Re:Ken Ham issues statement by Anonymous Coward · · Score: 0

      I don't understand how initial values are determined. (Is there some method by which the original ratio of the two elements is known? Or the proportion of radioactive isotopes?)

      They typically chose minerals that can't form with lead in them, but can form with uranium. So any lead found in them is likely to be due to uranium decaying after the mineral formed. The lead isotope that comes out is related to the particular uranium isotope that was at the start of the decay process, so that is how they can work out isotope ratios past times, and apply them to other minerals that might not have as clean of a dating process.

    8. Re:Ken Ham issues statement by Anonymous Coward · · Score: 0

      The initial amount of lead that can be incorporated into zircon (for example) is limited by its crystal structure, same for most other radiometric methods. Basically you select a mineral where not much daughter product should be there in the first place because it is mostly chemically excluded when the crystal forms. You also select a mineral that should have plenty of radioactive isotope (e.g., if U-Pb method, you pick a mineral with plenty of U, if K-Ar method you pick a mineral with plenty of K, etc.). Because there is only so much that can be stuffed in there, the initial amount is soon swamped by the radiogenic daughter product as time passes. Even leaving that chemical exclusion aside, you can determine the initial amount of lead or other initial isotope by using isochron methods, which are routinely done for U-Pb dating and other methods.

    9. Re:Ken Ham issues statement by Anonymous Coward · · Score: 0

      If you mean by leaving it around for ~4 billion years and seeing what happens, obviously not. But that's a rather narrow definition of what constitutes an experiment, and science does not run exclusively by sitting around and watching such experiments unfold. Plenty of lab experiments can be done on these mineral grains after the events have occurred to test whether an interpretation is plausible or not. Whether the experiment ran last Thursday or today doesn't matter. You don't have to run tests on the products of an event on the same day for it to be an experiment. We can be reasonably assured that physical laws have remained similar at different times. Why? Because the possibility they have changed over time has also been thoroughly tested (see below).

      For example, the natural nuclear reactor at Oklo had a sustained series of nuclear reactions ~1.7 billion years ago. That's the interpretation. It can be tested by all sorts of experiments on the rocks that occur at that site today. The fact the natural "experiment" was run so long ago is irrelevant to the scientific process. We study the products as they are now. As that wikipedia page explains, if there had been significant changes in many of the physical processes responsible for nuclear fission, then the resulting products would look very different. They are amazingly sensitive. The article refers to the atomic fine-structure constant as one of the things that was tested, but there are many others.

      This particular natural nuclear "experiment" couldn't be run today because in the intervening time too much of the 235U on the Earth has decayed (it decays faster than 238U), and a sustained nuclear reaction is no longer possible in the natural environment here. That's why artificial reactors have to enrich the 235U from the normal concentrations or use other techniques to sustain a fission reaction today.

  6. Lots of Iron around there by Harlequin80 · · Score: 3, Interesting

    The area these are found are extremely high in Iron content. There are a number of high grade iron ore mines nearby. I wonder if there is any link between the high iron content and the formation of these rocks.

    1. Re:Lots of Iron around there by Anonymous Coward · · Score: 5, Informative

      Not really. The 'Oldest Rock' they're talking about are actually individual mineral grains in a metamorphic rock that used to be sandstone. The zircon sand grains predate the rock they're in by about a billion years. The iron deposts you're talking about come from the same perioid of geologic time as the sandstone.

    2. Re:Lots of Iron around there by rve · · Score: 2

      The iron formations are about 2 billion years younger.

      The banded iron formations were formed by the earliest photosynthetic life, between 2.5 and 1 billion years ago. Oxygen produced by these single celled organisms formed iron oxide with dissolved iron ions in the oceans and precipitate on the ocean floor. This started when significant amounts of oxygen started dissolving in the water, and ended when most of the iron was used up. When that happened, the oxygen levels of the water suddenly increased, killing nearly all anaerobic life on earth, and opening the door for our aerobic ancestors.

    3. Re:Lots of Iron around there by Harlequin80 · · Score: 1

      That is fascinating - I had no idea the deposits were due to organics. I thought it was to do with some of the iron core solidifying on the surface after the impact.

  7. Obviously by El_Muerte_TDS · · Score: 3, Insightful

    The old stuff is always at the bottom of a pile.

    1. Re:Obviously by Rosco+P.+Coltrane · · Score: 4, Funny

      Yes but, Australia being upside down, the bottom is at ground level.

      --
      "A door is what a dog is perpetually on the wrong side of" - Ogden Nash
  8. Unfortunately by Greyfox · · Score: 5, Funny

    They had to kill the rock to confirm its age.

    --

    I'm trying to teach myself to set people on fire with my mind... Is it hot in here?

    1. Re:Unfortunately by Anonymous Coward · · Score: 0

      But is it the biggest rock?

    2. Re:Unfortunately by Anonymous Coward · · Score: 0

      Was. It was necessary to cut it in half to count the rings.

  9. Wow. by Anonymous Coward · · Score: 0

    It is almost as old as Larry King.

  10. Re:Amazing! by Anonymous Coward · · Score: 0

    It's just a poor, defenseless rock you sick bastard!

  11. I wonder what was underneath the rock they found . by Anonymous Coward · · Score: 0

    I wonder what was underneath the rock they found . . .

  12. Re: I wonder what was underneath the rock they fou by Anonymous Coward · · Score: 0

    It's an older rock, and they are saving it so they cab reveal it next year

  13. Did they finally date them? by dutchwhizzman · · Score: 5, Funny

    I'm sure AC/DC will be delighted with their new title of oldest rock on the planet.

    --
    I was promised a flying car. Where is my flying car?
    1. Re:Did they finally date them? by Anonymous Coward · · Score: 0

      Dumby-dum-dum a dumby-dum-dum a dumby dumby dumby dum-dum.

    2. Re:Did they finally date them? by ThatsDrDangerToYou · · Score: 1

      I'm sure AC/DC will be delighted with their new title of oldest rock on the planet.

      Well, I handle my rock with zircon encrusted tweezers.
      (Just had to get that off my chest.)

  14. Re:Amazing! by dbraden · · Score: 4, Informative

    I did not know that scientists had examined and dated every rock on (and every rock within) the Earth! The most spectacular part of this task was back when they dismantled Mt Everest, pebble by pebble, examining and dating every little rock, before re-constructing the mountain from all those sorted rocks.

    I agree with your general sentiment regarding fake science, however, a little bit of reading comprehension will go a long way.

    oldest rock ever found on Earth

    It's not like the summary says "The oldest rock on earth!".

  15. wtf? Do you even understand the subject? by SmallFurryCreature · · Score: 0

    Mount Everest is fairly young, we know this because unlike you scientists are aware of how Mount Everest was formed.

    You are just a flat earther in denial. Read up on geology.

    --

    MMO Quests are like orgasms:

    You may solo them, I prefer them in a group.

    1. Re:wtf? Do you even understand the subject? by rve · · Score: 2

      And you don't have all the answers either

      The 'rock' in question is a microscopic zircon crystal, not an actual chunk of rock. Think of it as a very hard grain of sand, that has been weathered off the rock in which it formed, deposited somewhere as sediment, which turned into sedimentary rock, and so on, perhaps a great many times, before it settled in the rock in which it was found.

      The Himalayas started uplifting some 50 million years ago, but that doesn't mean the material in it can be no more than 50 million years old. The rocks weren't melted in the process. Who knows, perhaps there is a grain of zircon embedded in a chunk of sandstone in the Himalayas that's even older. Perhaps a geologist can explain why this is or isn't possible, but it would definitely be like searching for a needle in a haystack.

      The reason for searching in places like Australia, is because exceedingly ancient rock formations are exposed there, significantly reducing the size of the haystack.

  16. Methodology by Marquis231 · · Score: 1

    I figure they cut the crystals open and counted the rings, all 4.374 billion of them.

  17. Re:Amazing! by Razalhague · · Score: 1

    Whenever you see a science headline that says something retarded, you should assume bad science journalism, rather than bad science.

  18. What are you on? by Anonymous Coward · · Score: 0

    This is real, serious science. The problem is you've got an imperfect impression of a summary of a news article that was written by a journalism major about a pretty technical academic paper. The actual science is way over your head.

    They're not claiming they've found the world's oldest rock. They're validating the dating method used on the oldest known mineral grain. It's very scientificly significant as there are some big implications for our understanding of how the Earth formed if it's as old as they think it is.

  19. Re: I wonder what was underneath the rock they fou by donaldm · · Score: 1

    It's an older rock, and they are saving it so they cab reveal it next year

    Now if you had moved your finger about 3 mm to your right of the letter b the sentence would make more sense. :)

    --
    There ain't no such thing as proprietary standards only proprietary formats. Standards are by definition open.
  20. Re:Amazing! by Anonymous Coward · · Score: 0

    While reading the summary is great the correctness of the summary in not an excuse for the headline being incorrect.
    I'm not sure if Slashdot or ABC is to blame on this one, both have equally incorrect and very similar headlines. I guess I blame Slashdot more, I expect more of them. (Even if I'm not surprised.) The editor should have made sure that the clearly inaccurate headline was corrected before putting it online.

  21. Rolling stones by bloodhawk · · Score: 1

    obviously these scientists haven't carbon dated Mick Jagger yet!

  22. Re:Amazing! by Farmer+Tim · · Score: 1

    The ABC is probably more at fault, they're supposed to have a dedicated science unit so it gets that kind of thing right.

    Of course, one could take the view that it's obvious that not every single rock on Earth has been dated, therefore the only people who really need the word "known" in the headline are pedants or the immensely thick.

    --
    Blank until /. makes another boneheaded UI decision.
  23. Mars rocks by Anonymous Coward · · Score: 0

    I have rocks from mars and Pluto in my back yard that are older.

    In fact, some are from the Big Bang.

  24. Re: I wonder what was underneath the rock they fo by KJSwartz · · Score: 1

    Don't you mean cm to the right?
    Egads! Americans using the metric system is like teaching dolphins to ride a bike. It's cute to watch them try!

  25. Sorry guys... by Anonymous Coward · · Score: 0

    And this is what happens. You put a bunch of convicts together for over a hundred years and it comes down to rock theft. http://www.canberratimes.com.au/act-news/onetonne-boulder-stolen-from-national-rock-garden-20140217-32use.html. The fact that Australia pre-emptively started hyping the value of rocks astounds me, yet here we are.

  26. Re: I wonder what was underneath the rock they fo by Anonymous Coward · · Score: 0

    Don't you mean cm to the right?
    Egads! Americans using the metric system is like teaching dolphins to ride a bike. It's cute to watch them try!

    geez I give up with both of ya. the big fail is ya gotta go.... and if you place your finger in your ass while reading this ya get the sentence blah blah blah blah blah.

  27. Ozzie! Ozzie! Ozzie! by Anonymous Coward · · Score: 0

    Take that, USAnians: We've got the biggest rock, AND the oldest. All you've got is the biggest hole. Ha ha.
    -- newall

  28. Soylent News... by Anonymous Coward · · Score: 0

    ...is people!

    Soylent News

    BUCK FETA!

    1. Re:Soylent News... by Anonymous Coward · · Score: 0

      Buck feta? So how much cheese for I get for a buck?

  29. Re: I wonder what was underneath the rock they fo by Anonymous Coward · · Score: 0

    Don't you mean cm to the right?
    Egads! Americans using the metric system is like teaching dolphins to ride a bike. It's cute to watch them try!

    3 cm?!?!? How big are the keys on your keyboard?

    Dude, do you have problems picking up coins if you drop them?

  30. What does this even mean? by Anonymous Coward · · Score: 0

    Aren't ALL rocks 4.5 billion years old?
    Or maybe it means that this particular rock happened to be on the surface of the earth 4.37 b years ago. I don't understand... sorry for my ignorance.

    Thanks.

  31. LOL by Anonymous Coward · · Score: 0

    Yeah, and Dick Cheney was there to throw it on someone! :D

  32. Priority queue by Dareth · · Score: 1

    It is a priority queue. Vegemite comes to the top first, then old rocks after.

    --

    I only look human.
    My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
  33. Creationism busted again by Murdoch5 · · Score: 0

    There is no way a rock can be older then 6000 years, it's impossible, of course so is logical and creationism.

  34. Re:Amazing! by Calavar · · Score: 2

    Fine, it's the oldest known rock, you pedant. It's still plenty interesting because the oldest known rocks up until know were only about 3.8 billion years old. There is the potential to learn a great deal about the early days of the earth from this rock. Oh, and obligatory xkcd: 1194

  35. Franklin institue by rjejr · · Score: 1

    Had my hand on a rock yesterday at the Franklin insitue in Philly that said it was 5.5 billion years old that was "found on Earth". (Well the rock didn't speak, thats what the sign read.) I know a meteor isnt created on Earth, but it was found there.

  36. Please stop... by Anonymous Coward · · Score: 0

    These might be the oldest rocks that have been found on earth, but please stop referring to them as the oldest rocks on earth.
    Those remain deep under the surface, in all likelihood.

  37. Upside Down? by Anonymous Coward · · Score: 1

    Assuming "North" is "Up" is just a variation on the flat-earth mentality... :-)

  38. Re: I wonder what was underneath the rock they fo by Brad1138 · · Score: 1

    I was thinking the same thing, I think about 1 cm sounds closer.

    --
    If you could reason with religious people, there would be no religious people