Forgot your password?
typodupeerror
Earth Science

Carbon Dating Gets an Update 137

Posted by samzenpus
from the looking-back dept.
ananyo writes "Climate records from a Japanese lake are set to improve the accuracy of carbon dating, which could help to shed light on archaeological mysteries such as why Neanderthals became extinct. Carbon dating is used to work out the age of organic material. But the technique assumes that the amount of carbon-14 in the atmosphere was constant — any variation would speed up or slow down the clock. Since the 1960s, scientists have started accounting for the variations by calibrating the clock against the known ages of tree rings. The problem is that tree rings provide a direct record that only goes as far back as about 14,000 years. Now, using sediment from bed of Lake Suigetsu, west of Tokyo, researchers have pushed the calibration limit back much further. Two distinct sediment layers have formed in the lake every summer and winter over tens of thousands of years. The researchers collected roughly 70-meter core samples from the lake and painstakingly counted the layers to come up with a direct record stretching back 52,000 years. The re-calibrated clock could help to narrow the window of key events in human history. Take the extinction of Neanderthals, which occurred in western Europe less than 30,000 years ago. Archaeologists disagree over the effects changing climate and competition from recently arriving humans had on the Neanderthals' demise. The more accurate carbon clock should yield better dates for any overlap of humans and Neanderthals, as well as for determining how climate changes influenced the extinction of Neanderthals."
This discussion has been archived. No new comments can be posted.

Carbon Dating Gets an Update

Comments Filter:
  • by Black Parrot (19622) on Friday October 19, 2012 @12:23AM (#41701869)

    The problem is that tree rings provide a direct record that only goes as far back as about 14,000 years.

    What's the problem? That's 7,984 years before the beginning of time.

    • by FatLittleMonkey (1341387) on Friday October 19, 2012 @12:51AM (#41701977)

      Aren't you curious what God was up to before genesis? I mean, if God has existed forever, and the universe is just 6000 years old, then what the hell was he doing all the rest of that time? Off making other universes? Were they successful or not? How much baggage does God have? Are the angels the result of those previous geneses? If not, when were the angels created? And the cherubs, oh why won't anyone think of the cherubs?!

      The theological implications of this new science are infinite and staggering.

      • by macbeth66 (204889) on Friday October 19, 2012 @01:16AM (#41702109)

        Aren't you curious what God was up to before genesis? I mean, if God has existed forever, and the universe is just 6000 years old, then what the hell was he doing all the rest of that time?

        Watching pr0n.

        Yes, it is a time paradox, but this is God we're talking about.

        • Watching pr0n.

          Eeeevery sperm is saaacred...

        • by Anonymous Coward

          Watching pr0n. Yes, it is a time paradox, but this is God we're talking about.

          No paradox. God is a lot like a Trafalmadorian, able to perceive all time at once. So if you can perceive all of time you can see future pr0n. No subscription necessary. (Best. Superpower. Ever.)

          Only, for some reason, that superpower does come with a blind spot or two. For instance, you won't see that the two hairless apes you make are going to defy you and eat your magic apples* in search of knowledge. It's OK though... you make the rules, and can hold them responsible until you get around to sending your

      • by IHateEverybody (75727) on Friday October 19, 2012 @01:52AM (#41702203) Homepage Journal

        As the documentary Battlestar Galactica explains, all this has happened before and all this shall happen again. God has created many worlds inhabited by humans but each time humans have created artificial intelligence which wiped them out. Often the AIs would continue and advance so far that they would believe themselves human and create their own AIs who would wipe them out as well. And so on and so on....Basically, God is a grad student running a giant experiment and he still hasn't gotten the bugs worked out just yet....

        • by Alsee (515537) on Friday October 19, 2012 @07:44AM (#41703599) Homepage

          God is a grad student

          That's the problem right there. God has been indoctrinated in radical liberal ideology by college professors.
          That's why we need strong conservative Christian leaders in power, to combat God's liberal bias.

          -

          • God is a grad student

            That's the problem right there. God has been indoctrinated in radical liberal ideology by college professors.
            That's why we need strong conservative Christian leaders in power, to combat God's liberal bias.

            -

            Ah, so that explains reality's liberal bias.

        • 'Abort, Retry, Fail?' was the phrase some wormdog scrawled next to the door of the Edit Universe project room. And when the new dataspinners started working, fabricating their worlds on the huge organic comp systems, we'd remind them: if you see this message, {always} choose 'Retry.' - CID Myers Alpha Centari

      • Re: (Score:2, Funny)

        Aren't you curious what God was up to before genesis?

        The same thing every man does first thing in the morning -- masturbating.

        I mean, if God has existed forever, and the universe is just 6000 years old, then what the hell was he doing all the rest of that time? Off making other universes? Were they successful or not?

        No. Once he saw what a mess he'd made of things, he put it all in the closet, got drunk, played X-Box, and forgot about the whole thing.

        How much baggage does God have?

        Let's just say him and the family attend regular therapy sessions...

        Are the angels the result of those previous geneses? If not, when were the angels created? And the cherubs, oh why won't anyone think of the cherubs?!

        No, the angels were "Version 1.0". After he realized he'd left off a few important bits, like genitals, he created man. It was a big improvement, but still far too buggy, so then he put out service pack 1, codename: Woman. Woman fixed

        • No, the angels were "Version 1.0". After he realized he'd left off a few important bits, like genitals, he created man.

          Of course angels have "important bits". Otherwise, how would the sons of God have knocked up the daughters of men (Genesis 6:4), creating the Nephilim [wikipedia.org] and giving God the excuse for the great server wipe of 1656 A.M. [wikipedia.org]?

      • by invid (163714)
        I'm an atheist but I'll answer that for you just to be the devil's (or God's) advocate. God created time 6000 years ago. God and heaven transcend all things material, including time.
      • if God has existed forever, and the universe is just 6000 years old, then what the hell was he doing all the rest of that time?

        Reconciling the six creative days of Genesis 1 with the billions of years of the scientific record is perfectly possible [wikipedia.org] because the creative days in Genesis 1 are not exactly literal. A day is like a thousand years to God (Psalm 90:4, 2 Peter 3:8). Consider that the seventh "day" of God's rest never had its "evening and [...] morning", implying that it is ongoing, and the discussion of God's rest in Hebrews 4 bears this out. We've hashed out day-age theory before on Slashdot [slashdot.org].

        • by geekoid (135745)

          The Hebrew word for day used in the genesis is account is “yom”, which is a definite 24-hour period.
          If a day is an era, why are an evening and a morning even mentioned?
          Adam was made on the sixth day (Genesis 1:26-31) which was supposedly thousand of years long. This was followed by the 7th day which was also thousands of years long. Following the 7th day, Adam fell into sin and was expelled from the Garden. This would make Adam Thousands of years old, but according to the Bible he was around

          • If a day is an era, why are an evening and a morning even mentioned?

            The use of "day" in Genesis 1 is an illustration, just as Jesus used illustrations in his ministry.

            Following the 7th day, Adam fell into sin and was expelled from the Garden.

            What makes you say "following the seventh day", as opposed to the seventh day being the present era?

          • by niado (1650369)

            How about: The passage is a parabole for mans fall from grace not literal in any way?

            Thisthisthis.

            The whole idea of taking the creation story of Genesis literally has only really gained traction since the mid-20th century.

        • the creative days in Genesis 1 are not exactly literal.

          If they'd, ummmm I mean He'd, marked the bits that were metaphorical (perhaps with a different font or something) it would have avoided a lot of confusion. We'd know for certain whether eating bacon cheeseburgers, sticking our willies up other men's bottoms or wearing a wool sweater with cotton trim is OK.

          • We'd know for certain whether eating bacon cheeseburgers, sticking our willies up other men's bottoms or wearing a wool sweater with cotton trim is OK.

            The Mosaic dietary law worked for its time, protecting the health of the Jews for over a millennium. Though many of the specifics were no longer needed by 33 CE due to improvements in general sanitation, the general principles on which God operates have not changed. True, the way the Judaizer controversy about circumcision was handled (Acts 15; Galatians 2:11-14) appears to repeal a lot of the old laws. But the way I see it, if a law follows from loving one's neighbor or is otherwise reiterated in the Greek

      • by mnooning (759721)
        FatLittleMonkey brings up great questions. Add all the protons, neutrons and electrons in the universe. Take that number of years to the exponential power of that number, then raise the result to the power of the resulting number, then do the same with the resulting number, then do it again for that resulting number of times, etc., etc.. No matter how long the number of years you think you can derive, it will be infinitesimally small compared to how far back in time you can really go. What was God doin
    • by Empiric (675968)
      And its almost as far back as when the first variant of this joke was told on Slashdot.
    • by girlintraining (1395911) on Friday October 19, 2012 @01:00AM (#41702025)

      What's the problem? That's 7,984 years before the beginning of time.

      *Steps out of the TARDIS* Hey, sorry to just pop in like this. Hello internet! Hello slashdot! So, anyway... where was I? Oh yes! Time! So, that idea's been out of style for, what, 500 years... so we were thinking, you must not be from around here, and so we've come to take you back to the 1400s. Don't give me that look! It's for your own good you know. Now, come along... we can't have people all out of time and space, it makes a real mess of the timestream. And these people, these beautiful beautiful people, they're about to do so much, yes, so very very much. And they don't need someone like you setting them back 600 years. Not now. So come on then, in you go!

      • by GNious (953874)

        well played, sir, well played!

      • What's the problem? That's 7,984 years before the beginning of time.

        *Steps out of the TARDIS* Hey, sorry to just pop in like this. Hello internet! Hello slashdot! So, anyway... where was I? Oh yes! Time! So, that idea's been out of style for, what, 500 years... so we were thinking, you must not be from around here, and so we've come to take you back to the 1400s. Don't give me that look! It's for your own good you know. Now, come along... we can't have people all out of time and space, it makes a real mess of the timestream. And these people, these beautiful beautiful people, they're about to do so much, yes, so very very much. And they don't need someone like you setting them back 600 years. Not now. So come on then, in you go!

        It is impossible to not hear this in Matt Smith's voice.

  • by sitarlo (792966) on Friday October 19, 2012 @12:26AM (#41701883)
    ...they dominate U.S. politics!
    • by Black Parrot (19622) on Friday October 19, 2012 @01:09AM (#41702079)

      ...they dominate U.S. politics!

      Probably because they also dominate the voting booths.

      • by morgauxo (974071)
        I want to move my previous comment to here please! "I doubt it. They (neanderthals) had bigger brains than Homo Sapiens Sapiens." Maybe offspring of Homo Floresiensis managed to escape their island and grew taller...
        • by mcgrew (92797) *

          They (neanderthals) had bigger brains than Homo Sapiens Sapiens

          It's been proven that the size of the brain does not correlate to intelligence. One data point: Einstein, whose brain was slightly smaller overall than normal (although certain areas of his brain were larger).

    • by morgauxo (974071)
      I doubt it. They had bigger brains than Homo Sapiens Sapiens.
  • Lucky grad student (Score:5, Interesting)

    by tsotha (720379) on Friday October 19, 2012 @12:41AM (#41701945)

    The researchers collected roughly 70-meter core samples from the lake and painstakingly counted the layers to come up with a direct record stretching back 52,000 years.

    Holy crap. "Painstakingly" doesn't even begin to cover counting 52,000 stripes in a core sample.

    • by nedlohs (1335013)

      104,000 according to "two distinct sediment layers have formed in the lake every summer and winter ".

    • by jersacct (1261566)

      Two distinct sediment layers have formed in the lake every summer and winter over tens of thousands of years.

      Actually, it's 104,000.

    • They made a game of it. See how many they could count in an hour, and then try to beat it.

    • by Black Parrot (19622) on Friday October 19, 2012 @01:02AM (#41702039)

      The researchers collected roughly 70-meter core samples from the lake and painstakingly counted the layers to come up with a direct record stretching back 52,000 years.

      Holy crap. "Painstakingly" doesn't even begin to cover counting 52,000 stripes in a core sample.

      No problem, at 80 hours a week [slashdot.org] a grad student should be able to finish well before his indentured servitude expires.

    • by Anonymous Coward on Friday October 19, 2012 @01:31AM (#41702149)

      Usually it's not just "count". Every layer must be checked to see if there are no bioturbations or other disturbances, that could hint a missing layer. Also layer thickness is measured in order to create deposition speed time model, to allow to correlate particular log with other borehole (varve) logs.
      http://en.wikipedia.org/wiki/Varve [wikipedia.org]
      http://en.wikipedia.org/wiki/Rhythmite [wikipedia.org]

      Of course, I haven't RTFA, as I'm located in a "leading science university" (rectors quote) and I don't have an access to Science.

    • The researchers collected roughly 70-meter core samples from the lake and painstakingly counted the layers to come up with a direct record stretching back 52,000 years.

      Holy crap. "Painstakingly" doesn't even begin to cover counting 52,000 stripes in a core sample.

      Now imagine how the CRU guys felt about getting hundreds of copy/pasted FOI requests for their painstaking work.

    • The researchers collected roughly 70-meter core samples from the lake and painstakingly counted the layers to come up with a direct record stretching back 52,000 years.

      Holy crap. "Painstakingly" doesn't even begin to cover counting 52,000 stripes in a core sample.

      Yep. And it's also one of the reasons the US's current fad for STEM in education will fail miserably. Real science is hard, boring, time consuming, and painstaking - it's not edutainment and it's not something that can be wrapped up in time for a

    • I've always had a problem with counting layers and assuming they correspond with years (whether a single layer, or several layers per year). Events like the eruption in Washington showed that many layers can be deposited in catastrophes, and given that neo-catastrophism is accepted by now, one would think these things would cause us to do a lot of criticism and re-thinking of the standard geology taught. Then again, that's hard work and largely boring correlation of a bunch of observations with how it can b
  • I don't get it ... (Score:5, Interesting)

    by sgunhouse (1050564) on Friday October 19, 2012 @01:19AM (#41702119)

    Wouldn't the amount of C-14 have been the same for humans and Neanderthals at any given time? Therefore while we may be unclear exactly when they went extinct (presuming Bigfoot is not a surviving branch of Neanderthals), we should have a pretty good idea in the overlap. Unless they use different dating methods for different events, this really shouldn't change the general picture.

    • Re: (Score:3, Insightful)

      by dadelbunts (1727498)
      I think the point of this article is that before this, they could only really look back 14,000. Since Neanderthals went extinct 30,000 years ago, that doesnt help much. Now they can look back 52,000 years. I know no one reads the article, but at least read the summary. Its all right there. I figured it out and im drunk.
      • by riverat1 (1048260)

        I think the point of this article is that before this, they could only really look back 14,000.

        No, carbon 14 dating is good for around 60,000 years before its level gets to low for accuracy. They could measure that all along. This research merely extends the accuracy that tree rings provided back to 52,000 years thus narrowing the range of years found for a specimen.

      • by sFurbo (1361249) on Friday October 19, 2012 @03:23AM (#41702513)
        No, they could go back further, up to 55,000 years, I think, by assuming that the C-14/C-12 ratio has always been the same. This is not quite the case, as the levels of cosmic radiation changes, so the production rate of C-14 changes. If we have an object that is known to have a certain age, we don't need to guess, we can compare directly. However, really old objects with known dates are hard to come by. You more or less need an annual cycle going up to today, so that you have an anchored chronology. Previously, tree ring data was the best anchored chronology that could be carbon dated (I assume there is too little C in glacial ice, I don't know why corals can't be used. Perhaps sea water might not always be in C equilibrium with the atmosphere?), so we could only go back 14,000 years. Now, we have an carbon-dated anchored chronology going back 52,000 years, so carbon dating gets much more accurate.
        • Since most C14 is generated in the upper atmosphere, there is no telling when the Carbon in sea water was absorbed, meaning there's no base line.
    • presuming Bigfoot is not a surviving branch of Neanderthals

      That's such a pretty idea lol

    • by sFurbo (1361249)
      Climate changes is also a possibility, which AFAIK, is dated from ice cores.
  • by erice (13380) on Friday October 19, 2012 @01:24AM (#41702133) Homepage

    I'm amazed that they found a clear seasonal pattern in a lake going back 52,000 years. Lakes are short lived structures, geologically speaking and 52,000 years is quite far into the last ice age. I guess the lake somehow managed to avoid being glaciated and managed to avoid being washed away by the melt waters. Impressive! I haven't located an ice age map of Japan so I don't know how much, if any, of Japan was actually covered by ice. It is far enough North but the ice sheet was not uniform. (Parts of Alaska were ice free)

    • by riverat1 (1048260)

      I looked up the Würm glaciation on Google and found this map. [factsanddetails.com] Being west of Tokyo there wasn't a lot of glaciation there.

  • by Anonymous Coward

    The problem isn't just that C-14 isn't a constant over time.. It's varies over different parts of the planet. How does there lake account for that?

    • by sFurbo (1361249)
      I can't vary that much over different parts of the planet. For one hemisphere, the atmosphere is mixed on at least a monthly basis. Crossing the equator takes a bit longer, bu nevertheless, it is more or less complete after 5 years [wikipedia.org]. There is some problems with sea dwelling creatures, as water might come from the deep sea, and not be in equilibrium with the atmosphere.
  • That carbon dating has always been as accurate as you can afford. You decide the date that you need in order to confirm your thesis, send your sample to as many labs or as many times as your budget allows, then pick the closest answer from the essentially random set of results.

    Anyone on the inside of the inside care to confirm or refute that?

    • It's not that bad. Carbon14 dating does have a sound scientific basis and is ballpark correct. However there is sufficient variation between labs that it's clear the measuring process itself is not precise and, worse, there are clear systemic differences between C14 dates and dendrochronology. It's not clear what causes this - variation in C14 over time? over different regions? different rates of decay? - so anything which helps reconcile the figures is good.
    • by Anonymous Coward on Friday October 19, 2012 @06:16AM (#41703231)

      That carbon dating has always been as accurate as you can afford. You decide the date that you need in order to confirm your thesis, send your sample to as many labs or as many times as your budget allows, then pick the closest answer from the essentially random set of results.

      Anyone on the inside of the inside care to confirm or refute that?

      I'm not on the inside, but I've read some of the papers.
      Every few years there is an International Radiocarbon Intercomparison, where a batch of different types of samples are sent to most of the world's labs (~100) to date. The results are then compared. Overall stats are published anonymously, and individual labs can publish their results if they want.
      The most accurate method (AMS) shows error rates of ~1%, while older methods give error rates of up to 10%.
      Of course there are some classes of samples which present special problems; the study samples are ones which don't present major contamination issues.
      The full study from 2003 is open access: here [arizona.edu]

    • by Anonymous Coward

      There are multiple techniques available that can be more or less precise (e.g., regular C-14 dating versus atomic mass spectrometry), and these will inevitably yield slightly different results because of the normal scientific measurement process. But essentially random results and testing until you get the one you want? Uh, no. In fact, one of the clearest demonstrations that the technique is not random is that you can take a series of samples from different layers of sediment, and within the analytical

    • by geekoid (135745)

      "Anyone on the inside of the inside care to confirm or refute that?"
      how do you refute nonsense?

      While lab shopping does happen, it's onyl good for that ONE event and doesn't hold up over times.
      If your thesis runs counter to C14, BUT goes along with current understanding of the field, then you have made a huge discovery. Far more important then the thesis itself.

  • ...strudents are slacking here.  Get back to your work. Recount!
  • The Internationally agreed Radiocarbon calibration curve (IntCal) - co-ordinated from Belfast University - takes info from ice-cores, lake sediment cores, tree-rings, corals, etc from the Southern and Northern hemispheres (there's an offset between them) puts them together (this work is done by statisticians using specially developed methods rather than other scientists using off-the-shelf techniques) and although some scientists would rather that only their work was used (as they can then claim whatever 'a
  • Reading one of the articles ( http://researchcommons.waikato.ac.nz/bitstream/handle/10289/3622/Hogg%20Intcal09%20and%20Marine09.pdf [waikato.ac.nz] ) seems to make it clear that the Lake Suigetsu project is a player, but only one of many, in the project to develop a better INTCAL chronology. It may be obvious to some, but any single dataset is not particularly useful until it is corroborated with many others. The Suigetsu project has been at work for several years and, although there has been some revision made to their b

  • by kelemvor4 (1980226) on Friday October 19, 2012 @08:48AM (#41704183)
    I'm in! Should I bring flowers and candy?
  • What bothers me about the article is that they pretend that the best data we had was 14000 years. In the 90's this lake was used to calculate back as far as 45000 years. See this article in Science from 1998.

    Science 20 February 1998:
    Vol. 279 no. 5354 pp. 1187-1190
    DOI: 10.1126/science.279.5354.1187

    http://www.sciencemag.org/content/279/5354/1187.abstract [sciencemag.org]

There are running jobs. Why don't you go chase them?

Working...