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Earth Science

Research Finds Carbon Dating Flawed 625

eldavojohn writes "New research funded by the National Science Foundation at the University of Miami is showing that carbon dating (the 13C/12C ratio used to infer age) in the ocean can only be trusted up to 150 million years ago. From the primary researcher, 'This study is a major step in terms of rethinking how geologists interpret variations in the 13C/12C ratio throughout Earth's history. If the approach does not work over the past 10 million years, then why would it work during older time periods? As a consequence of our findings, changes in 13C/12C records need to be reevaluated, conclusions regarding changes in the reservoirs of carbon will have to be reassessed, and some of the widely-held ideas regarding the elevation of CO2 during specific periods of the Earth's geological history will have to be adjusted.' While this research doesn't necessarily throw carbon dating out the window, it should cause people to rethink so many theories about early life that revolved around ages of sediment in the oceans."
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Research Finds Carbon Dating Flawed

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  • Title (Score:5, Insightful)

    by Idiomatick ( 976696 ) on Wednesday September 10, 2008 @10:45PM (#24956501)

    Is frustrating, oh no its only accurate for 150million years. JUST WAIT for the ID people to jump all over this and start with the whole dinosaurs didnt exist, invisible man made everything 5000years ago. *sighs* these people live in my neighborhood and are going to harass me with their ignorance again.

    • Re:Title (Score:5, Insightful)

      by eebra82 ( 907996 ) on Wednesday September 10, 2008 @11:02PM (#24956639) Homepage

      Is frustrating, oh no its only accurate for 150million years. JUST WAIT for the ID people to jump all over this and start with the whole dinosaurs didnt exist, invisible man made everything 5000years ago. *sighs* these people live in my neighborhood and are going to harass me with their ignorance again.

      I realize that you're somewhat frustrated, but this does not prove science wrong. After all, that's what science is all about. You make a discovery and you prove it. Eventually, the discovery is disproved/adjusted/strenghtened due to new findings. And again, and again, and again.

      • Re:Title (Score:5, Insightful)

        by Chris Pimlott ( 16212 ) on Wednesday September 10, 2008 @11:08PM (#24956689)

        It's not the science he's upset about, it's the reporting.

      • Re: (Score:3, Insightful)

        by PunkOfLinux ( 870955 )

        Now, if only the creationists would adjust their fucking theory...

        • Re: (Score:2, Insightful)

          by ObitMan ( 550793 )

          As soon as it is disproved/adjusted/strenghtened due to new findings.

          • Re:Title (Score:5, Insightful)

            by jeevesbond ( 1066726 ) on Thursday September 11, 2008 @01:03AM (#24957799) Homepage

            Now, if only the creationists would adjust their fucking theory...

            As soon as it is disproved/adjusted/strenghtened due to new findings.

            Creationism is not a theory. Two properties of a theory are: must be possible to disprove; and must be able to predict results of a test. Creationism is capable of neither of these things.

            It is impossible to test or disprove that an invisible man is living in the sky, therefore this is the realm of philosophy and spirituality. These things that have their place, but should not be interfering, aiming to replace, or masquerade as good science.

            • Re: (Score:3, Insightful)

              by Hatta ( 162192 )

              Two properties of a theory are: must be possible to disprove; and must be able to predict results of a test.

              Aren't those the same thing? If a theory predicts the results of a test, and you get different results, you have disproved that theory. Likewise, if a theory makes no predictions, how is it possible to disprove it?

        • Re:Title (Score:5, Insightful)

          by Mattsson ( 105422 ) on Thursday September 11, 2008 @03:57AM (#24958851) Journal

          They don't have a theory.
          They don't have a hypothesis.
          They don't even have a conjecture, since that is something that is unproven but deemed likely to be true

          All the creationists have is a set of guesses.
          Hmm... In the eyes of a creationists, their guesses probably are likely to be true, so they can say that creationism is a conjecture.

    • Well duh! (Score:5, Funny)

      by EmbeddedJanitor ( 597831 ) on Wednesday September 10, 2008 @11:06PM (#24956679)
      I've been trying to date carbon based life forms for a while now and it is damn tricky.

      I was going to switch to one of those plastic blow up dolls until I found out that they're loaded with carbon too!

      • Re: (Score:3, Funny)

        by Migity ( 1199059 )
        Doesn't posting on /. make it harder to date carbon based life forms??? You may want to look into that.
    • Re: (Score:3, Interesting)

      Serious question to elucidate those who are misinformed (including myself): What effect does the Industrial Revolution and the subsequent history's use of fossil fuels have on carbon dating?

      • Re:Title (Score:4, Informative)

        by Alsee ( 515537 ) on Thursday September 11, 2008 @04:32AM (#24959011) Homepage

        What effect does the Industrial Revolution and the subsequent history's use of fossil fuels have on carbon dating?

        Interesting question.

        It would have no effect on anything already old and dead. It wouldn't really have any effect on normal uses of carbon dating. What the Industrial Revolution and burning fossil fuels has done is taken large amounts of "old" C14-depleted carbon out of the ground and dumped it into the atmosphere as CO2. Radiation hitting the upper atmosphere slowly turns some of that carbon into "fresh" radioactive C14. However I believe it takes several thousands of years for that conversion to C14 to really rise to its full level. So this means that for a few thousand years the carbon in the air is going to be somewhat C14 depleted - it reads as "old" in carbon dating. Plants will consume that "old" carbon CO2 from the air and photosynthesize it into the sugars and starches and proteins and everything else that makes up the plant. This should have the effect of dead modern plants testing as probably a few hundred years older than they actually are. It will have the same effect on animals - the plants eat "old" carbon from the air and then the animals eat the "old" carbon from the plants. The animals build their bodies out of that "old" carbon in their food.

        So the effect will likely be maybe a few hundred year shift in the apparent readings for materials from this general era, but carbon dating readings will be calibrated against the expected results to take that effect into account. Future archaeologists may have trouble telling the difference between 1700's materials and 2000's materials. They may read about the same.

        My estimates may be off on the size of the effect, but that is how carbon dating works and that is approximately the sort of impact it should have.


    • by copponex ( 13876 ) on Thursday September 11, 2008 @12:30AM (#24957523) Homepage

      You need to learn the bible for insight into much of western thought, but you should also learn it for the fun that can be had with it's biblically ignorant followers.

      First, ask them what the ten commandments are. This will trip 95% of them up and they'll walk away without bothering you. If they say that the commandments are not important, tell them you think the same about the rest of the Bible.

      Claim you don't believe in Yahweh because you don't believe in infanticide. They'll give you a strange look, and then ask them to read Psalm 137:9, which is in context, Jews daydreaming about smashing their enemies' infants to pieces.

      Ask them if they eat lobster, or if there's a girl in the group, if they wear pants. If they say yes, ask them why they support the homosexual agenda, since all three are abominations according to the bible.

      They will go to great lengths to explain away why what they do or don't is covered by some painful translation-based loopholes, and what everyone else does is what's really wrong. This is the basic definition of a hypocrite, which concerns my favorite scripture:

      'As he taught, Jesus said, "Watch out for the teachers of the law. They like to walk around in flowing robes and be greeted in the marketplaces, and have the most important seats in the synagogues and the places of honor at banquets. They devour widows' houses and for a show make lengthy prayers. Such men will be punished most severely.'

      Don't get me wrong, the world would be a great place of everyone followed the advice of Jesus, but most of them have never read more than ten pages of their Holy Book.

      • by commodoresloat ( 172735 ) * on Thursday September 11, 2008 @01:49AM (#24958119)

        Don't get me wrong, the world would be a great place of everyone followed the advice of Jesus

        That's for sure! If everyone learned to turn the other cheek it would be so much easier to overpower and enslave them all and run the place! MUWAHAHAHAHA!!!!

      • by mcrbids ( 148650 ) on Thursday September 11, 2008 @02:25AM (#24958337) Journal

        Have you ever watched The Bible is Repulsive []? It's a great 15 minutes. Spare it. You won't regret it.

        I used this video one time while talking to a fundamentalist. We were downtown, there was a gay rights parade (I'm a left-coaster) and the usual fundamentalist Christians on the other side of the street. Several blocks away, I struck up a conversation with a guy who was hanging around.

        I guess it was because I'm obviously hetero, and fairly well-dressed, short hair, etc. because he assumed that I was on the Christian Fundamentalist side. I joshed with him for a while, talked about the wife, the kids, working, paying bills, blah blah blah. I mentioned something about strictly following the good book, and tisked about the guys down the street. He was very adamant that we should "follow the good book".

        Having planted that seed, I got the kids into the conversation again a little while later. I started in with how I have lots of kids (I do) and how they sometimes misbehave. He agreed, and then I talked about what do you do about it? How do you keep your kids in line!?!? You have important values you want to teach! and he was with me all the way.

        And then I said:

        "It's a good thing that the good book thought of this, two. When my oldest son snuck out and smoked a joint with his buddies, I grabbed some bricks and killed him, right there on the spot". I played it perfectly, too! He was speechless. "Yeah, I believe that the good book should be taken literally, and it's pretty clear, right there in the Deuteronomy, when your children misbehave, you stone them to death".

        As he cursed and walked away, I hollered out: "And the cops haven't even investigated! It's been 2 years now!"

        I don't think I've ever laughed so hard in all my life...

    • by j_w_d ( 114171 ) on Thursday September 11, 2008 @02:53AM (#24958505)

      The OP never bothered to read the article, or has some strange ideas about carbon dating. The article title is just wrong. The 13C/12C ratio doesn't offer a date of any kind. What it has been used for, as the article says, is to infer when life begins to be an important player in the planetary environment. The article explains that a researcher has identified flaws in how the ratio is estimated. Nothing what-so-ever to do with "carbon dating." Instead it has to do with estimated dates of the ratio changes. The dates are probably Uranium based dates (you can't date anything more than about 50,000 years old using radiocarbon). The C13/C12 ratio estimated from proxies FOR that date are apparently in error.

  • Oh no! (Score:4, Funny)

    by Anonymous Coward on Wednesday September 10, 2008 @10:45PM (#24956505)

    carbon dating can only be trusted up to 150 million years ago

    Does that mean we'll never know for sure how old John McCain is?

  • Spore? (Score:5, Funny)

    by wcspxyx ( 120207 ) on Wednesday September 10, 2008 @10:53PM (#24956563)

    Will there be a patch?

    • Re: (Score:3, Funny)

      by Anonymous Coward

      I think Spore already supports Intelligent Design.

  • Not news (Score:5, Insightful)

    by orkybash ( 1013349 ) <tim DOT bocek AT gmail DOT com> on Wednesday September 10, 2008 @10:55PM (#24956583)
    Anyone who uses any form of radiometric dating knows that there are limits to the accuracy. The fact that a new limit was discovered doesn't make the technique "flawed", though I will grant that it may call for re-evaluation of some results. Anyone who thinks that the fact that these limits exist is news, though, is terribly misguided.
    • Re:Not news (Score:4, Insightful)

      by DrCJM ( 827451 ) on Wednesday September 10, 2008 @11:03PM (#24956647)
      Not wanting to be a pedant, but 13C/12C dating isn't radiometric. Neither isotope of carbon is radioactive.

      OK, may I do want to be a pedant. :)

      • Re:Not news (Score:5, Informative)

        by Anonymous Coward on Wednesday September 10, 2008 @11:12PM (#24956757)

        The title "Carbon Dating Flawed" was a poor choice as there are at least 2 different carbon dating methods, and the most common and well-known, radiocarbon-14 dating, isn't affected by the finding.

      • Based on the article, it appears that it isn't "dating" either: it is used to infer biological activity. Presumably, the sample would be dated using other isotopes.

    • Re: (Score:3, Insightful)

      The fact that a new limit was discovered doesn't make the technique "flawed"

      Well, to be proper, it does make it flawed, it just doesn't mean that the technique is worthless.

  • It's like always close to an order of magnitude off.
  • by charlesbakerharris ( 623282 ) on Wednesday September 10, 2008 @11:27PM (#24956927)
    For next-generationcarbon dating, try
  • So much hate... (Score:3, Insightful)

    by megamerican ( 1073936 ) on Wednesday September 10, 2008 @11:36PM (#24957031)

    Why are there so many people in this thread worried about what other people are going to think about this? So many reactions were so similar it seems to be a Pavlovian response.

    It is really sad that people who consider themselves to be smarter than others would immediately resort to the grade-school tactic of making fun of others because they are different than you in an attempt to make yourself feel accepted by the group.

    I must be new here.

    P.S. I'm no creationist or ID advocate.

    • Re:So much hate... (Score:5, Insightful)

      by jfengel ( 409917 ) on Thursday September 11, 2008 @12:04AM (#24957307) Homepage Journal

      Because the creationists have been pushing an untenable decision for quite some time, using extremely dubious tactics. They've achieved a disturbing amount of political success by exploiting people's ignorance of science.

      Imagine how much they can accomplish when they can point to scientists actually being wrong about something. Never mind that it does nothing to bolster their position. All they need is to sow doubt about science.

      Scientifically, this is merely interesting. Politically, it's an immense hassle on a battle which wastes a huge amount of time with zero scientific merit.

      So yeah, you're gonna get some bitching when this sort of thing happens.

    • Re:So much hate... (Score:4, Insightful)

      by unlametheweak ( 1102159 ) on Thursday September 11, 2008 @12:29AM (#24957511)

      Why are there so many people in this thread worried about what other people are going to think about this?

      It matters because any FUD (apparent or real) about science will be exploited by those whose political ideologies diverge with scientific findings. For political ideologues, any apparent negative-sounding news means exploitable FUD. This can effect how education is funded and mandated, among other things. Science unfortunately is not an Ivory Tower sheltered from politicians.

  • by IICV ( 652597 ) on Wednesday September 10, 2008 @11:37PM (#24957037)
    A classic example of science journalists who don't have any idea what they're writing about! Ratios of 13C/12C in ocean sediments are used as a proxy of paleoproductivity and a weak proxy of past temperatures. Generally 18O/16O is a better temperature proxy, and is just as easy to obtain. No one really relies on carbon isotopes for anything, except sometimes methane hydrate release. Carbon dating, like figuring out how old something is, is done with 14C/12C, and it is a well known fact that carbon dating is only useful back to 50,000 years ago. Bad science journalism makes me sad inside.
    • by Kesch ( 943326 ) on Wednesday September 10, 2008 @11:47PM (#24957159)

      The article at least seemed to have a fairly good grasp of the subject. I guess they may have overstated the implications a bit to make the article seem less boring.

      Although, no one even seems to read far enough into the article to come away with that naive misunderstanding. Instead people seem to think this related to carbon-14 dating and going into off-topic discussions about creationism when the off-topic discussion for this article should in-fact be global warming.

    • Pop sci (Score:3, Insightful)

      Write anything that attracts eyeballs and sells magazines or gets hits.

      Don't let science or facts stand in the way of business.

      Unfortunately this serves as "science" for the unwashed masses where public opinion and being fashionable count more than the quest for "truth".

    • by rve ( 4436 ) on Thursday September 11, 2008 @12:40AM (#24957611)

      I agree. Long ago I noticed that journalists are often spectacularly wrong about stuff I happen to know a lot about.

      How can I trust them to be right about things I don't know much about?

      • Re: (Score:3, Insightful)

        by smoker2 ( 750216 )
        I watched a BBC program about global warming last week, where the well meaning and apparently ill-qualified scientist presenting made several glaring scientific errors. The most laughable was when he described the Keeling curve. All very interesting, up until he summed up the segment by saying that now that Keeling had taken measurements of the growth of CO2 in the atmosphere over a long period, we now had irrefutable proof that humans caused global warming.
        Absolute bollocks. All Keeling had done wa
  • by 93 Escort Wagon ( 326346 ) on Thursday September 11, 2008 @12:51AM (#24957683)

    Carbon dating is based on the decay rate of Carbon 14, and has a pretty short limit geologically speaking - 70,000 years with enrichment methods, but closer to 50,000 years using traditional counting. It's possible accelerator 14C dating has pushed this slightly - I haven't worked in this field for about a decade.

    The tie-in to "dating" in this context is that sediments are deposited over time, and if they're undisturbed you can drill a core that'll give you (theoretically) a record of the 13C/12C ratio over time - but that ratio is not being used for dating AT ALL. The only way you could use the ratio for ersatz dating is if the sediment shows an annual 13C/12C cycle due to annual temperature variations - then you can count the cycles the same way you can count tree rings (BTW 13C/12C in tree rings varies in this same sort of summer/winter - or spring/fall - pattern). In any case, the actual dating of the sediments is usually done using a different, longer-lived, radiometric isotope ration such as you find with rubidium-strontium (That particular isotope pair may not be the best fit for sea sediments; like I said, I've been out of this for a while. We mainly did 13C/12C in trees and 18O/16O in ice cores).

  • by Coolhand2120 ( 1001761 ) on Thursday September 11, 2008 @01:13AM (#24957877)
    I've read at least four posts that "ID supporters are going to go crazy about this". And I've read zero posts from ID supporters going crazy. The fact is that ID could mean anything from you believe in Vishnu to you believe in the Intergalactic space council that seeds terraformed planets and has planted here, long ago, alien DNA by visiting spacecraft now trapped in a small storage locker somewhere in the Alpha Centauri system. ID is SO vague it can't possibly be argued against, or taught outside of saying "Someone or something may have made all this".

    It's sort of like saying my Science is better than your imaginary friend. If some lunatic fringe of the radical evangelical right wing Christians want to disbelieve obvious science fact does not mean that everyone who believes in ID is so naive. Even Christians believe in science, and a lot of them believe that god made physics! But it's not something you can, or should argue about, you end up looking like a bigger fool than the guy who believes in a geocentric universe or some such nonsense.

    You shouldn't pigeonhole anyone who believes in something you can't possibly prove or disprove as someone who is inherently stupid and who rejects science. There are far too many scientists who believe in ID for that argument to be valid.
    • Re: (Score:3, Informative)

      by Nimey ( 114278 )

      You're assuming that lots of IDers hang out on Slashdot. Not so. Many of them hang out on local newspaper forums, or on websites catering to their kind, or on political-argument sites, or for the retirees with too much time on their hands, they write letters-to-the-editor.

  • Full paper (Score:4, Informative)

    by rrohbeck ( 944847 ) on Thursday September 11, 2008 @01:58AM (#24958185)
  • by pln2bz ( 449850 ) * on Thursday September 11, 2008 @02:02AM (#24958207)

    Slashdot should have ran the more interesting story pertaining to nuclear decay rates that came up this week, which my nuclear physicist associate (Oliver Manuel) forwarded to me ...

    Evidence for Correlations Between Nuclear Decay Rates and Earth-Sun Distance []

    Seach the Firehose for "decay rate" and you'll find my submission, which was rejected (not complaining actually, just a bit confused).

    And it's not even that this result is the first time it's been noticed. Russian researcher Simon Schnoll has performed *thousands* of simple geiger counter isotope decay rate experiments and noticed the same exact thing -- that there is an astrophysical influence to decay rates ...

    Russian Discovery Challenges Existence of 'Absolute Time' []

    The idea that nuclear decay rates might not be random is pretty paradigm-changing. We can doubt the results, but shouldn't we at least be talking about it? It seems to me like a very important finding.

    Isn't this even more pertinent to the concept of anthropogenic warming than the absolute dating article Slashdot went with???

  • by mbone ( 558574 ) on Thursday September 11, 2008 @06:29AM (#24959563)

    This is not about Carbon dating at all (that's about looking at the decay of Carbon 14, produced by cosmic ray radiation high in the atmosphere), this is about the Carbon 12/13 isotope ratio used as an indicator of biological activity in the distant past. Basically, what they say they found was that this is only trustworthy in deep ocean sediments, not on land or in island sediments, and you can only find deep ocean sediments for the last 150 million years or so, due to plate tectonics recycling the sea floor.

    This will not affect geological dating at all. It may affect the interpretation of some work regarding, e.g., extinction events. It's hard to say without looking in detail at the other work (they may have several lines of evidence, etc.).

  • by AMESN ( 1313525 ) on Thursday September 11, 2008 @11:22AM (#24962921)
    "Miscalculation" is the wrong word. Geologists are nuanced (unlike this headline) in how they interpret C-13 vs. C-12, especially for early Earth history. The PNAS paper is not about the ratio being flawed, it's about another way to interpret the activity of the shallow ocean versus the deep, open ocean. The paper is simply another line of scientific discussion, itself part of the scientific method.

The opossum is a very sophisticated animal. It doesn't even get up until 5 or 6 PM.