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Australia Earth Science

Confirmed: Earth's Oldest Rock In Australia 74

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."
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Confirmed: Earth's Oldest Rock In Australia

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  • by jamesjw ( 213986 ) on Monday February 24, 2014 @01:04AM (#46321165) Homepage

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

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

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

    Now what?

  • by Brad1138 ( 590148 ) <brad1138@yahoo.com> on Monday February 24, 2014 @01:19AM (#46321201)
    "there's this book..."
    • "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.

      • by Improv ( 2467 )

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

        • by Mashdar ( 876825 ) on Monday February 24, 2014 @10:45AM (#46323575)

          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 [wikipedia.org]

          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.

          • by Mashdar ( 876825 )
            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.
  • by Harlequin80 ( 1671040 ) on Monday February 24, 2014 @01:26AM (#46321229)

    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.

    • by Anonymous Coward on Monday February 24, 2014 @02:20AM (#46321367)

      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.

    • by rve ( 4436 )

      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, killin [wikipedia.org]

      • 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.

  • Obviously (Score:4, Insightful)

    by El_Muerte_TDS ( 592157 ) on Monday February 24, 2014 @01:34AM (#46321253) Homepage

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

  • by Greyfox ( 87712 ) on Monday February 24, 2014 @01:42AM (#46321281) Homepage Journal
    They had to kill the rock to confirm its age.
  • by dutchwhizzman ( 817898 ) on Monday February 24, 2014 @02:24AM (#46321385)
    I'm sure AC/DC will be delighted with their new title of oldest rock on the planet.
    • 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.)

  • I figure they cut the crystals open and counted the rings, all 4.374 billion of them.
  • obviously these scientists haven't carbon dated Mick Jagger yet!
  • There is no way a rock can be older then 6000 years, it's impossible, of course so is logical and creationism.
  • 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.

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