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Post by sawltydawg on Oct 27, 2009 7:20:48 GMT 10
"carbon dating doesn't work" ....have you ever heard someone say that.... here is how you respond to such uneducated idealistic hogwash: the video makes reference to "The age of the earth made easy" here it is:
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Post by brillbilly on Oct 28, 2009 9:04:16 GMT 10
yep the world was created in a week in october 4004BC,lol,lv it
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Post by shatnerswig on Oct 29, 2009 4:26:08 GMT 10
I think what the real problem with carbon dating is not the method but the application of its use or more specifically .. its mis use ... there is a lengthly discussion on carbon dating in michael cremos book forbidden archeology which explains carbon dating .
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Post by brillbilly on Oct 30, 2009 4:30:34 GMT 10
i like it when they apply C14 to megaliths,megaliths being stone cannot be dated with C14,only organic matter can,so dates for ancient structures made of stone can cause rear problems for dating the sites accurately.What can be dated? For radiocarbon dating to be possible, the material must once have been part of a living organism. This means that things like stone, metal and pottery cannot usually be directly dated by this means unless there is some organic material embedded or left as a residue. As explained below, the radiocarbon date tells us when the organism was alive (not when the material was used). This fact should always be remembered when using radiocarbon dates. The dating process is always designed to try to extract the carbon from a sample which is most representative of the original organism. In general it is always better to date a properly identified single entity (such as a cereal grain or an identified bone) rather than a mixture of unidentified organic remains. The dating principle Once an organism dies the carbon is no longer replaced. Because the radiocarbon is radioactive, it will slowly decay away. Obviously there will usually be a loss of stable carbon too but the proportion of radiocarbon to stable carbon will reduce according to the exponential decay law: R = A exp(-T/8033) where R is 14C/12C ratio in the sample, A is the original 14C/12C ratio of the living organism and T is the amount of time that has passed since the death of the organism. By measuring the ratio, R, in a sample we can then calculate the age of the sample: T = -8033 ln(R/A) -------------------------------------------------------------------------------- Complications The simplified approach described above does not tell the whole story. There are two reasons why the radiocarbon date is not a true calendar age: Half life: this is not exactly as originally measured by Libby; the original half life is still used in calculations in order to maintain consistency and because other effects are more important Atmospheric variations: the radiocarbon concentration of the atmosphere has not always been constant; in fact it has varied significantly in the past Both of these complications are dealt with by calibration of the radiocarbon dates against material of know age. Further complications arise when the carbon in a sample has not taken a straightforward route from the atmosphere to the organism and thence to the measured sample. Common examples are: Contamination: where material from the soil or conservation work becomes incorporated into the sample resulting in an admixture of carbon with a different radiocarbon content; the purpose of chemical pre-treatment is to remove all such material Reservoir effects: these occur, for example, when some of the carbon reaches the sample by way of the oceans; because the radiocarbon composition of the oceans differs from that of the atmosphere, this can lead to erroneous dates; stable isotope measurements can be used to see if this effect is present since the stable isotope concentration of the oceans is also different c14.arch.ox.ac.uk/embed.php?File=dating.html
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Post by shatnerswig on Oct 30, 2009 4:53:58 GMT 10
carbon dating CAN be used on stone but it is not accurate ... it will give you a general idea of how long a rock face has been exposed to the elements because organic material , however small ,will grow in the tiny cracks and crevices.,,, that can be analized .so for example ,if you sample say an ancient stone structure (taking a sample where there there was once growth) you may not be able to determine the exact date(which by the way carbon dating does not do anyway) but you can determine with reasonable accuracy that the structure is at least as old as the growth that was on the exposed sample. so if the sample come out to be 3000 years old you could come to the conclusion that the building is at least 3000 years old ... it could be 5000 or 10000 or how ever old ,but again you would have reasonable proof that is atleast 3000 because of the imbedded organic material.
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Post by brillbilly on Oct 30, 2009 5:14:46 GMT 10
i agree mate,organic material on stone can be C14 dated but as we know C14 has its flaws the further back in time you go,it does work but its not exact.The C-14 Method or Radiocarbon Method is the oldest physical method, which allows to determine the age of a thing. The method is named after its principle, it is based on the natural radioactive decay of the carbon isotope C14. It was developed in the 1950s by a team of scientists under Professor Willard F. Libby of the University of Chicago. Libby received the Nobel Prize in Chemistry "for his method to use Carbon-14 for age determinations in archaeology, geology, geophysics, and other branches of science." in 1960. First a word on how the name of this method is written. The C14 is a isotope of carbon, which is otherwise C12 or C13. The C means carbon, the number gives the atomic weight rounded. There are various ways to write it, C14, C-14, 14C or most accurate 14C. Unfortunately the most accurate way to write it is not very practical on HTML page, as it influences the line height. It is impractical even for books and papers, so the C14 notation is most commonly used So now about the way it works! Carbon is a very common element. The atmosphere contains a certain amount of carbon dioxide, a gas which is composed on carbon and oxygene. But there are three different kinds of carbon, which differ in a way that all are still true carbon, but their atomic structure is different. Two are called C12 and C13, carbon with an atomic weight of twelve or thirteen respectively - which are the normal and stable carbon - and the last one is C14, an isotope of carbon, which is subject to a very slow and harmless radioactive decay. This decay results in radiation and a stable isotope. So if you take some carbon with C12, C13 and C14 and wait long enough, you will only have C12 and C13 left. The dating using any kind of isotopes is based on determining the ratio between stable isotopes and non-stable isotopes. If we know where we started, and if we know the half-life (amount of time it takes for half of the isotopes to break down) we can compute the necessary time to reach todays state. This is the theory. Now lets have a short look at archaeological daily life. Live on earth is based on carbon, which is gathered from food or from the air. The carbon dioxide is reduced by plants into carbon and oxygen in a process called photosynthesis. So the plants contain carbon from the atmosphere. In an excavation we often find things which contain some carbon. Charcoal in furnaces or fire places is common, also charcoal used for drawing cave paintings. Other organic remains also contain carbon, like leather, wooden tools, seeds or other food and sometimes bones. So it should be rather easy to find something with carbon in a layer we want to date. But one second, we do not know one thing: where did this carbon start? Which ratio did we originally have? Probably it was similar to today, with 98.89% C12, 1.11% C13 and 0.0000000001% C14. Unfortunately it is not that easy, but it was possible to make a timetable of this ratio. And so we are able to determine the age of carbon if we measure the amount of C14. C14 dating is a very usefull dating method with some important drawbacks. It works only if we have some carbon and know its origin. Unfortunately there is a much bigger drawback: the half-life of C14 is only 5730±40 years. So the amount of C14 vanishes rather fast, and if it is too little to be measured exactly, we can not determine the age any more. So this method is only usefull for archaeological dating. It works very well for the last 30,000 years, but becomes more and more inaccurate for older samples. And there is a last important drawback. We must know the original ratio to calculate the age. It works well if we have a plant, so we know it grew up using carbon dioxide from the air. Speleothems are also often based on carbon dioxide, so it is possible to determine Arizona Board of Regents (University of Arizona).
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Post by sawltydawg on Nov 1, 2009 11:20:28 GMT 10
the differences in results from the different kinds of tests...is the reason that they have different kinds of tests.....very rarely do scientists ever use just one test...they will use as many test as possible in order to obtain the largest amount of data .
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Post by brillbilly on Nov 2, 2009 1:59:26 GMT 10
the differences in results from the different kinds of tests...is the reason that they have different kinds of tests.....very rarely do scientists ever use just one test...they will use as many test as possible in order to obtain the largest amount of data . lol,i like the different tests as they are better than the other different tests
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Post by blacky on Nov 4, 2009 3:51:53 GMT 10
no it doesnt! ;D
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Post by shatnerswig on Nov 6, 2009 8:47:37 GMT 10
It does but its only for specific things ... carbon dating is not all inclusive for dating things and even the analitical methods If anyone really knows about the nature of it has pros and cons each side can always be picked apart with certian scenareos. I agree that accuracy isnt exact either Its more of a ball bark estimate by normal human standards .. you cannot pin point a specific day month year or millenium even but from an archeological standpoint it puts the object within a specific historical time line. now what happens when the archeological evidence that is found to be a certian age and it doent fit into the mainstream archeological time line?ie: ooparts? that would be a nice debate.
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