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Carbon-14 Dating:     more books (21)

The carbon-14 method of age determination by Frank H. H Roberts, 1952 Application of a new carbon-14 counting technique to earthquake studies (Open file report / U.S. Geological Survey) by Allen B Tucker, 1981 Carbon-14 counting by accelerator mass spectrometry: Application to earthquake dating by Allen B Tucker, 1985 Carbon 14: Nuclear clock for archeology (Scientific American. [Offprint]) by Willard F Libby, 1968 Dendrochronologic calibration of the carbon-14 time scale by P. E Damon, 1972 National radiocarbon 14 measurement and applications by J. Laurence Kulp, 1950

lists with details

21. Carbon-14 Dating
    Carbon14 Dating is a method used by scientists to find the age of an organic compound. This form of determining an object's age was discovered in 1949 at the University of  
    http://itech.pjc.edu/falzone/projects/research_report_carbon_dating.pdf

22. The Method
    BY THOMAS HIGHAM Everything which has come down to us from heathendom is wrapped in a thick fog; it belongs to a space of time we cannot measure.  
    http://www.c14dating.com/int.html
    
    Extractions: BY: THOMAS HIGHAM "Everything which has come down to us from heathendom is wrapped in a thick fog; it belongs to a space of time we cannot measure. We know that it is older than Christendom, but whether by a couple of years or a couple of centuries, or even by more than a millenium, we can do no more than guess." [Rasmus Nyerup, (Danish antiquarian), 1802 (in Trigger, 1989:71)]. Nyerup's words illustrate poignantly the critical power and importance of dating; to order time. Radiocarbon dating has been one of the most significant discoveries in 20th century science. Renfrew (1973) called it 'the radiocarbon revolution' in describing its impact upon the human sciences. Oakley (1979) suggested its development meant an almost complete re-writing of the evolution and cultural emergence of the human species. Desmond Clark (1979) wrote that were it not for radiocarbon dating, "we would still be foundering in a sea of imprecisions sometime bred of inspired guesswork but more often of imaginative speculation" (Clark, 1979:7). Writing of the European Upper Palaeolithic, Movius (1960) concluded that

23. THE PROBLEMS WITH CARBON-14 DATING
    Carbon14 dating is an inaccurate method due to its reliance on faulty assumptions.  
    http://contenderministries.org/evolution/carbon14.php

24. Carbon 14 Dating: What Assumptions Should We Take?
    As a Creationist, what should we do with Carbon 14 dates? We will look at both the process of Carbon 14 dating as well as the assumptions needed to go through the process of  
    http://www.creation-science-prophecy.com/C14.htm

25. Carbon Dating Background
    Carbon14 Dating Background Information _ Carbon dating is used to determine the age of biological artifacts up to 50,000 years old.  
    http://www.acad.carleton.edu/curricular/BIOL/classes/bio302/Pages/CarbonDatingBa
    
    Extractions: Carbon-14 Dating: Background Information Carbon dating is used to determine the age of biological artifacts up to 50,000 years old. This technique is widely used on recent artifacts, but teachers should note that this technique will not work on older fossils (like those of the dinosaurs which are over 65 million years old). This technique is not restricted to bones; it can also be used on cloth, wood and plant fibers. Carbon-14 dating has been used successfully on the Dead Sea Scrolls, Minoan ruins and tombs of the pharohs among other things. What is Carbon-14? Carbon-14 is a radioactive isotope of carbon. Its has a half-life of about 5,730 years. The short half-life of carbon-14 means its cannot be used to date extremely old fossils. Levels of carbon-14 become difficult to measure and compare after about 50,000 years (between 8 and 9 half lives; where 1% of the original carbon-14 remains undecayed). How is Carbon-14 formed? Carbon-14 is created from nitrogen-14 in the upper atmosphere of the earth. Radiation from the sun collides with atoms in the atmosphere. These collisions create secondary cosmic rays in the form of energentic neutrons. When these neutrons collide with nitrogen-14 in the atmosphere carbon-14 can be created. Nitrogen normally occurs in a seven proton, seven nuetron, nitrogen-14 state. When it collides with an energetic neutron it becomes carbon-14, with six protons and eight neutrons and gives off a hydrogen atom with one proton and zero neutrons.

26. Carbon 14 Dating: Can Dates Fit 6000 Year Scenario?
    As a Creationist, what should we do with Carbon 14 dates? We will look at both the process of Carbon 14 dating as well as the assumptions needed to go through the process of  
    http://www.creation-science-prophecy.com/C14fp.htm

27. Carbon 14 Dating - Worked Chemistry Problems
    Here's a worked example of the calculation for carbon 14 dating of organic material.  
    http://chemistry.about.com/od/workedchemistryproblems/a/c14dating.htm
    
    Extractions: zWASL=1;zGRH=1 zGCID=this.zGCID?zGCID+" test11":" test11" zJs=10 zJs=11 zJs=12 zJs=13 zc(5,'jsc',zJs,9999999,'') zDO=0 Home Education Chemistry Search By Anne Marie Helmenstine, Ph.D. , About.com Guide zSB(3,3) Introduction In the 1950s W.F. Libby and others (University of Chicago) devised a method of estimating the age of organic material based on the decay rate of carbon-14. Carbon-14 dating can be used on objects ranging from a few hundred years old to 50,000 years old. Carbon-14 is produced in the atmosphere when neutrons from cosmic radiation react with nitrogen atoms: N + C + H Free carbon, including the carbon-14 produced in this reaction, can react to form carbon dioxide, a component of air. Atmospheric carbon dioxide, CO , has a steady-state concentration of about one atom of carbon-14 per every 10 atoms of carbon-12. Living plants and animals that eat plants (like people) take in carbon dioxide and have the same

28. Carbon-14 Dating (scientific Technology) -- Britannica Online Encyclopedia
    carbon14 dating (scientific technology), method of age determination that depends upon the decay to nitrogen of radiocarbon (carbon-14). Carbon-14 is continually formed in  
    http://www.britannica.com/EBchecked/topic/94839/carbon-14-dating
    
    Extractions: document.write(''); Search Site: With all of these words With the exact phrase With any of these words Without these words Home My Britannica CREATE MY carbon-14 da... NEW ARTICLE ... SAVE Table of Contents: carbon-14 dating Article Article Related Articles Related Articles Supplemental Information Supplemental Information - Spotlights Spotlights External Web sites External Web sites Citations ARTICLE from the carbon-14 dating also called radiocarbon dating , method of age determination that depends upon the decay to nitrogen of radiocarbon (carbon-14). Carbon cosmic rays interacting with the atmosphere.

29. Carbon-14 Dating
    Carbon14 Dating Most everyone has heard of Carbon dating on the news or elsewhere sometime in the past years. Ever wonder what “Carbon dating” means and  
    http://www.chem.uwec.edu/Chem115_F00/nelsolar/chem.htm
    
    Extractions: Most everyone has heard of Carbon dating on the news or elsewhere sometime in the past years. Ever wonder what �Carbon dating� means and why it is so important? In this article I hope to explain the theoretical and physical science behind Carbon dating, and discuss how it affects our lives and the validity of the process. Scientists use Carbon dating for telling the age of an old object, whose origin and age cannot be determined exactly by normal means. Because of this method Chemistry has become intertwined with History, Archeology, Anthropology, and Geology. (Poole) Many items that have been thought to come from one time have been tested and found out to actually come from a few thousands years beforehand. Places where historians believed that human civilization came to exit say, only 2,000 years ago, have actually been proven to have had some form of human civilization more than 4,000 years ago. (Poole) Fine art collectors have used Carbon dating to determine if a piece of antique art is actually genuine. Some have saved themselves several thousands of dollars by testing the piece before they bought it and finding out that it is not the original, but a very clever modern copy. (Poole) But how is this done? What are the ides behind carbon dating? All organic material has decaying Carbon-14 in it. However, plants and animals that are still alive constantly replace the supply of carbon in their systems and so the amount of Carbon-14 in the system stays almost constant. Once a plant or animal dies the Carbon is no longer being regenerated and so the Carbon-14 starts to decay. In this way, by measuring the amount of Carbon-14 in the body of a prehistoric animal or plant, a scientist can deduce when the plant or animal died.

30. Carbon-14 Dating
    A creation science resource megasite where you can find an assortment of free curriculum, participate in discussion forums, and browse an exhaustive number of internet references.  
    http://www.nwcreation.net/presentations/carbon-14.html

31. Carbon 14 Dating
    Carbon 14 Dating . Creation Position. Many living things are not in equilibrium for C14 exchange; the shells of living mollusks show radiocarbon ages of up to 2300 years.  
    http://www.fsteiger.com/carbon14.html
    
    Extractions: Creation Position Many living things are not in equilibrium for C-14 exchange; the shells of living mollusks show radiocarbon ages of up to 2300 years. The rate of carbon 14 radioactive decay may have been different in the past. The amount of carbon dioxide in the atmosphere may have been different in the past. The assumption of a constant ratio of C-14 to C-12 is invalid; equilibrium would require about 30,000 years, and the C-14/C-12 ratio appears to be increasing still. Evolution Position The following was extracted from an August 27, 1996 post by Howard Hershey (hershey@indiana.edu). Additional information was added. Carbon exists in the atmosphere in the form of carbon dioxide, CO . It can be present either as stable carbon 12 or unstable carbon 14. Carbon 14 is formed from ordinary nitrogen 14 in the atmosphere by the action of cosmic rays. The cosmic rays produce neutrons which bombard the nitrogen atoms, resulting in a neutron being absorbed and a proton being ejected. The N-14 atom of 7 protons and 7 neutrons is transformed into a C-14 atom of 6 protons and 8 neutrons. The carbon-14 atom immediately combines with atmospheric oxygen to form carbon dioxide. A steady state results in which the rate of decomposition of carbon 14 is matched by the rate of formation of new C-14 by cosmic rays. The result is that carbon 14 is present as a constant percentage of the total carbon in the atmosphere, although it does change slightly depending upon the amount of cosmic radiation reaching the atmosphere. However, a correction can be made on the basis of carbon 14 readings on items whose age is known from counting tree rings and archeological records.

32. Carbon 14 Dating - Math Central
    Archaeologists use the exponential, radioactive decay of carbon 14 to estimate the death dates of organic material. The stable form of carbon is carbon 12 and the radioactive  
    http://mathcentral.uregina.ca/beyond/articles/ExpDecay/Carbon14.html
    
    Extractions: Math Central - mathcentral.uregina.ca Math Beyond School return to top Carbon 14 Dating Archaeologists use the exponential, radioactive decay of carbon 14 to estimate the death dates of organic material. The stable form of carbon is carbon 12 and the radioactive isotope carbon 14 decays over time into carbon 12 and other particles. Carbon is naturally in all living organisms and is replenished in the tissues by eating other organisms or by breathing air that contains carbon. At any particular time all living organisms have approximately the same ratio of carbon 12 to carbon 14 in their tissues. When an organism dies it ceases to replenish carbon in its tissues and the decay of carbon 14 to carbon 12 changes the ratio of carbon 12 to carbon 14. Experts can compare the ratio of carbon 12 to carbon 14 in dead material to the ratio when the organism was alive to estimate the date of its death. Radiocarbon dating can be used on samples of bone, cloth, wood and plant fibers. For example, say a fossil is found that has 35% carbon 14 compared to the living sample. How old is the fossil?

33. Carbon-14 Dating | Define Carbon-14 Dating At Dictionary.com
    –noun radiocarbon dating. Use carbon14 dating in a Sentence See images of carbon-14 dating Search carbon-14 dating on the Web Origin 1955–60  
    http://dictionary.reference.com/browse/carbon-14 dating

34. Carbon 14 Dating - Ask.com
    Top questions and answers about Carbon14-Dating. Find 77 questions and answers about Carbon-14-Dating at Ask.com Read more.  
    http://www.ask.com/questions-about/Carbon-14-Dating

35. Carbon Dating
    How does carbon 14 dating work? Is carbon dating accurate? Why do they call it radio carbon dating? Can we use radioactive carbon dating to determine the age of the earth?  
    http://www.allaboutarchaeology.org/carbon-dating.htm
    
    Extractions: This is how carbon dating works: Carbon is a naturally abundant element found in the atmosphere, in the earth, in the oceans, and in every living creature. C-12 is by far the most common isotope, while only about one in a trillion carbon atoms is C-14. C-14 is produced in the upper atmosphere when nitrogen-14 (N-14) is altered through the effects of cosmic radiation bombardment (a proton is displaced by a neutron effectively changing the nitrogen atom into a carbon isotope). The new isotope is called "radiocarbon" because it is radioactive, though it is not dangerous. It is naturally unstable and so it will spontaneously decay back into N-14 after a period of time. It takes about 5,730 years for half of a sample of radiocarbon to decay back into nitrogen. It takes another 5,730 for half of the remainder to decay, and then another 5,730 for half of what's left then to decay and so on. The period of time that it takes for half of a sample to decay is called a "half-life."

36. Carbon-14 Dating - Definition Of Carbon-14 Dating By The Free Online Dictionary,
    car bon14 dating (k r b n-f r-t n, -f r-) n. See radiocarbon dating. carbon-14 dating. n (Social Science / Archaeology) another name for radiocarbon dating  
    http://www.thefreedictionary.com/carbon-14 dating

37. Carbon-14 Dating
    The problem with Carbon14 dating. Science Miracles Evolution Creation Carbon Dating. Inspiration Partial Contradictions  
    http://www.wrestedscriptures.com/c03carbon-14/carbon14.html
    
    Extractions: In order to critically appraise the claim that C-14 "definitely proves" the age of man to be at least 30,000 years, a description of C-14 dating is required: The C-14 dating method is only reliable if the general assumption of the uniformity of nature is valid. Uniformity of nature is the belief that present causes solely have operated in the past. Within this general assumption are two particular assumptions: That fossilized creatures when living had as much C-14 as similar things have today. That the rate of decay of C-14 has remained constant (i.e., that the rate of decay has not changed in the interval from when the creatures lived to the present day).

38. Carbon 14 Dating
    Carbon 14 Dating Understand what carbon-14 is and what part it plays in our biosphere. Discover how it can be used as a dating technique.  
    http://www.allaboutarchaeology.org/carbon-14-dating-faq.htm
    
    Extractions: To understand how carbon 14 dating works, you first have to understand what carbon-14 is and what part it plays in our biosphere. All living creatures are made in part of carbon. As they live and grow and interact with their environments they consume more and more carbon. By far, the most abundant form of carbon is carbon-12. Carbon-12 is a stable isotope; that is, it doesn't decay naturally. Carbon-14 on the other hand is an unstable isotope; that is, it decays naturally over time. Carbon-14 is also relatively rare. It is produced naturally in the atmosphere and mixes with carbon-12 becoming part of our planet's biosphere. As creatures consume carbon from their environment and incorporate it into their bodies, they consume both carbon-12 and carbon-14. When a creature dies, it ceases to consume more carbon. Since carbon-12 doesn't naturally decay while carbon-14 does, once a creature stops incorporating more carbon into its body, the ratio of carbon-12 to carbon-14 in its body begins to change, with less carbon-14 per carbon-12 as time passes. Since creatures incorporate carbon-12 and carbon-14 into their bodies at about the same ratio as it occurs in the atmosphere during their lifetimes, by looking at the ratio in the atmosphere today and by comparing it to the ratio as it is found in the specimen we are examining, we are able to determine when the specimen stopped consuming more carbon-14 (i.e. when it died). This is, of course, assuming that we know how long it takes for carbon-14 to decay and that we know that the ratio of carbon-12 to carbon-14 in the atmosphere today is about the same as if was during the creature's lifetime. If either assumption is wrong carbon-14 dating doesn't work.

39. Carbon 14 Dating Calculator
    Carbon 14 Dating Calculator. To find the percent of Carbon 14 remaining after a given number of years, type in the number of years and click on Calculate.  
    http://dwb.unl.edu/Teacher/NSF/C03/C03Links/www.all.mq.edu.au/online/edu/egypt/c
    
    Extractions: To find the percent of Carbon 14 remaining after a given number of years, type in the number of years and click on Calculate. Years Carbon Dating Calculator Carbon 14 left = percent To find the years that have elapsed from how much Carbon 14 remains, type in the C-14 percent and click on Calculate. Percent C-14 Carbon Dating Calculator Years = More about Carbon Dating Many thanks to Geophysical Institute, University of Alaska Fairbanks for permission to use the following extract All carbon is not created equal. The same element can have different isotopes or atomic numbers-in effect, the weights of their nuclei differ. Carbon has three isotopes, known as carbon 12, carbon 13, and carbon 14, often called simply C-12, C-13, and C-14. The carbon in the carbon dioxide we breathe, for example, is about 99 percent C-12. The remaining one percent is virtually all C-13. That's fine, because the two isotopes are the same element. The very rare carbon 14 is another matter, though, because it is radioactive. By losing an electron, every atom of C-14 eventually will decay into an atom of N-14; that is, it will turn into ordinary nitrogen. As radioactive substances go, C-14 doesn't last long. Half of any number of atoms of carbon 14 will have become nitrogen 14 after 5730 years have passed. That's simply another way of saying that C-14 has a half-life of 5730 years.

40. Carbon-14 Dating?
    Posted by Steve Price on June 24, 1999 at 044448 In Reply to Re Sources of error in Carbon14 dating? posted by Wendel Swan on June 23, 1999 at 150329  
    http://www.turkotek.com/salon_00021/messages/68.html
    
    Extractions: Follow Ups Post Followup Salon FAQ Posted by Steve Price on June 24, 1999 at 04:44:48: In Reply to: Re: Sources of error in Carbon-14 dating? posted by Wendel Swan on June 23, 1999 at 15:03:29: Dear Wendel, Thanks for the URL on C-14 dating. It is fairly thick going, but very informative and useful. First, the random errors in the method are unlikely to be reduced to where the spread of uncertainty is less than 100-200 years as a 95% confidence interval. That is, it is possible to do so in principle but unlikely to happen in practice. This is disturbing when we are trying to use the method in a range of less than 500 years. Second, the systemic errors are horrendous. Jim Allen mentions that Kajitani believes washing a rug can make it appear to be 100 years older by C-14. Exposure to smoke can add up to 1,000 years to the apparent age. Exposure to certain seawaters can add hundreds of years. All of these systemic errors are in the same direction. Any rug we have is likely to have been washed, every tribal rug can be assumed to have been exposed to smoke, and there's no way of knowing which ones had an ocean voyage en route to our collectors. It would appear to me that, on the basis of what I know so far, C-14 dating can only set a maximum age on a piece, and even that will have a very large uncertainty associated with it. Does anyone out there know the Arizona C-14 folks well enough to ask them to post a professional's take on the subject? It might really help a lot.

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