61. Re: Carbon-14 Dating Of Crude Oil Re carbon14 dating of crude oil. To radsafe@romulus.ehs.uiuc.edu; Subject Re carbon-14 dating of crude oil; From Khalid Aleissa kaleissa@kacst.edu.sa ; http://www.vanderbilt.edu/radsafe/0001/msg00420.html

Date Prev Date Next Thread Prev Thread Next ... Thread Index Re: Carbon-14 dating of crude oil To radsafe@romulus.ehs.uiuc.edu Subject : Re: Carbon-14 dating of crude oil From kaleissa@kacst.edu.sa Date : Fri, 14 Jan 2000 13:33:33 +0300 Organization : KACST References 001401bf58d2$a2e29d00$8842edc7@ronald Reply-To kaleissa@kacst.edu.sa http://www.ehs.uiuc.edu/~rad/radsafe.html http://www.ehs.uiuc.edu/~rad/radsafe.html Khalid Aleissa e-mail: kaleissa@kacst.edu.sa ************************************************************************ The RADSAFE Frequently Asked Questions list, archives and subscription information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html References Re: Carbon-14 dating of crude oil From: "Ron L. Kathren" <rkathren@tricity.wsu.edu> Prev by Date: journalists' (or reporters') ethics Next by Date: Re: C-14 and Petroleum Prev by thread: Re: Carbon-14 dating of crude oil Next by thread: Carbon-14 dating of crude oil Index(es): Date Thread

62. BYU Professors Differ With Creationist On Evolution And Carbon-14 Dating Y professors differ with creationist on evolution and carbon14 dating. carbon-14 dating is another subject the scientists disagreed on. http://www.lds-mormon.com/evolutn1.shtml

Y professors differ with creationist on evolution and carbon-14 dating By DEGAN JOHN KETTLES Universe Staff Writer Although most members of The Church of Jesus Christ of Latter-day Saints believe in the biblical account of the world's creation , BYU professors say LDS views differ significantly from the beliefs of a religious movement called creationism. In a recent creationism conference at Victory Baptist Church in Orem, Dr. Don White of Montana State University refuted evolution based on beliefs that no intermediary stages between animals have been found, that carbon-14 dating is not accurate and that evolutionist theories are actually a religion. Creationism, according to writer Isaac Asimov , is a belief system that is based upon unshakable faith in a literal interpretation of all the words of the Bible. White reflected creationist beliefs stating that he believed in the Genesis, not the human, account of history. Some BYU zoology professors disagree with White's basic reasons for refuting evolution. "We see macroevolution (an evolution from one species to another) very clearly in the

63. Radiocarbon Dating Radiocarbon Dating and the Bible. Is carbon14 dating (or radiocarbon dating) always reliable and beyond question? Is carbon-14 dating useless before 2,000 BC? http://www.biblequery.org/radiocarbon.htm

Radiocarbon Dating Radiocarbon Dating and the Bible Is carbon-14 dating (or radiocarbon dating) always reliable and beyond question? Are all radioactive dating methods unreliable? Have carbon-14 (C ) dates millions of years old been proven wrong? Is carbon-14 dating useless before 2,000 B.C.? Or are the above statements all false, and the truth is something else? Since there are many misconceptions about carbon-14 dating, this paper will explain the principle, the method, some early problems with it, and its current trustworthiness. While many probably have not thought about it before, carbon-14 dating relates to Christianity and Judaism in interesting ways. This method addresses questions on the Shroud of Turin, the archaeological reliability of the Bible, reliable preservation of the Bible, and the Young Earth Theory. The Principle All plants take in carbon from carbon dioxide in the atmosphere. All animals take in carbon by eating the plants. Now most carbon has a molecular weight of 12. However, solar radiation creates a small percentage of carbon with two extra neutrons and a molecular weight of 14. A carbon-14 atom is radioactive; it eventually loses an electron and a neutrino and changes to nitrogen-14. Its half-life is 5,730 30 years, so it never has nor can be used to date carbon samples millions of years old.

64. Next Page Previous Page Next page Previous page carbon14 dating. carbon brick. Brick usually made from crushed coke and bonded with pitch or tar. carbon dating. Seecarbon-14 dating. http://www.maden.hacettepe.edu.tr/dmmrt/dmmrt181.html

Next page Previous page carbon-14 dating A method of determining an age in years by measuring the concentration of carbon-14 remaining in an organic material, usually formerly living matter, but also water, bicarbonate, etc. The method is based on the assumption that assimilation of carbon-14 ceased abruptly on the death of an organism and that it thereafter remained a closed system. The method is useful in determining ages in the range of 500 to 30,000 years or 40,000 years, although it may be extended to 70,000 years by using special techniques involving controlled enrichment of the sample in carbon-14. Syn: radio carbon dating ; carbon dating. AGI carbonaceous a. Coaly, containing carbon or coal, esp. shale or other rock containing small particles of carbon distributed throughout the whole mass. Fay b. Carbonaceous sediments include original organic tissues and subsequently produced derivatives of which the composition is organic chemically. AGI carbonado Cryptocrystalline diamond; compact, tough, opaque, dark-gray to black, cleavage absent; generally in rounded masses, also in angular broken

65. Layers Of A Lake Refine Carbon Dating Counting thin white layers of dead algae, each less than a millimeter thick, the researchers calibrated carbon14 dating back to 43,000 BC, http://more.abcnews.go.com/sections/science/dailynews/carbon0220.html

Bottom of Lake Refines Carbon Dating Technique This Died How Long Ago? SCIENCE HEADLINES added Counting thin white layers of dead algae, each less than a millimeter thick, the researchers calibrated carbon-14 dating back to 43,000 B.C. Living organisms breathe, eat and drink carbon-14. But once they die, no more carbon-14 comes in. So it starts decaying, letting archaeologists date objects up to 50,000 years old. (For Stongehenge, they dated organic matter in the silt below.) (ABCNEWS.com) By Kenneth Chang ABCNEWS.com Feb. 23 At the bottom of Lake Suigetsu, thin layers of microscopic algae have been piling up for more than 45,000 years. Reading them like tree rings, scientists have improved their carbon-14 dating technique. (ABCNEWS.com) The rest of the year, dark clay sediments settle on the bottom. The alternating layers of dark and light count the years like tree rings. That has allowed scientists to fine-tune a technique called carbon-14 dating, which is used to pin down dates for artifacts tens of thousands of years old. Japan Kitagawa, along with Johannes van der Plicht of Groningen University in the Netherlands examined the Suigetsu sediments and reported their findings in the latest issue of the journal

66. PhysicsWeb - Carbon Clock Could Show The Wrong Time From PhysicsWeb, Carbon dating is a mainstay of geology and archaeology, but an enormous peak discovered in the amount of carbon14 in the atmosphere between 45 thousand and 11 thousand years ago casts doubt on the biological carbon cycle that underpins the technique. http://physicsweb.org/article/news/5/5/7/1

Advanced site search news January February March April May June July August September October November December Show summaries quick search Search the news archive. Previous News for May 2001 Next Carbon clock could show the wrong time 10 May 2001 Carbon dating is a mainstay of geology and archaeology - but an enormous peak discovered in the amount of carbon-14 in the atmosphere between 45 thousand and 11 thousand years ago casts doubt on the biological carbon cycle that underpins the technique. The study led by physicist Warren Beck of the University of Arizona, US, could also affect estimates of how quickly the Earth can re-absorb the excess carbon dioxide generated by fossil fuels (J W Beck et al Science to appear). Stalagmite stopwatch Living organisms and some geological features absorb stable carbon-12 and radioactive carbon-14, which are present in the air in a well-known ratio. This is part of the carbon cycle - the recirculation of carbon through the oceans, atmosphere, plants and animals. Scientists use carbon dating to determine when objects ceased to absorb carbon by measuring how much of the carbon-14 - which has a half-life of 5730 years - has decayed. But Beck and colleagues believe that the ratio of stable and radioactive carbon in the atmosphere may have changed considerably over the last 50 thousand years. This raises questions about the accuracy of carbon dating for very old objects. Beck and colleagues tested slices of a half-metre long stalagmite that grew between 45 000 and 11 000 years ago in a cave in the Bahamas. Stalagmites are calcium carbonate deposits left behind when carbon dioxide evaporates out of cave seepage water. They found that carbon-14 concentrations were twice their modern level during that period. Current records of the levels of carbon-14 in the atmosphere only cover the last 16 thousand years, and this discovery extends those records a further 30 thousand years.

67. Carbon 14 Dating Radiocarbon dating is based on the rate of decay of the unstable carbon14 which is produced by cosmic radiation of neutrons in the upper atmosphere acting on http://www.duke.edu/~clc8/radiocarbon.html

Radiocarbon Dating (C-14) History Willard Frank Libby Basis of the Method There are three naturally-occurring isotopes of carbon (carbon-12, carbon-13, and carbon 14). Radiocarbon dating is based on the rate of decay of the unstable carbon-14 which is produced by cosmic radiation of neutrons in the upper atmosphere acting on Nitrogen: 14N + n => 14 C + p (p is a proton) Since plants and animals intake carbon throughout their lives, the amount of 14C in their bodies remains in equilibrium with the atmospheric levels of 14C throughout their lifetime. When a plant or animal dies, it stops intaking carbon dioxide and the amount of 14C present in their body is reduced as the 14C decays and no additional 14C is incorporated to replace it. This unstable carbon-14 decays by the following process: 14C => 14 N + b (b is a beta particle, an electron) The amount of time it takes for half of all the radioactive carbon to decay is referred to as the half-life. If one knows the atmospheric level of 14C and measures the amount of 14C in an organic sample, one can calculate the number of half lifes that have elapsed since the organism died and estimate the how long ago the organism died. Since the half-life of carbon is approximately 5730 years, this method is best used to date objects under 60,000 years old because after 10 or so half-lives there is just not enough 14C left to be measured accurately. There are other radioactive elements with longer half-lives that can be used to measure older samples.

68. Radiocarbon Dating Radiocarbon, or carbon14, dating is probably one of the most widely used and best known absolute dating methods. The Limitations of Carbon 14 dating. http://id-archserve.ucsb.edu/Anth3/Courseware/Chronology/08_Radiocarbon_Dating.h

Chronological Methods 8 - Radiocarbon Dating Radiocarbon, or Carbon-14, dating is probably one of the most widely used and best known absolute dating methods. It was developed by J. R. Arnold and W. F. Libby in 1949, and has become an indispensable part of the archaeologist's tool kit since. It's development revolutionized archaeology by providing a means of dating deposits independent of artifacts and local stratigraphic sequences. This allowed for the establishment of world-wide chronologies. Where does C -14 Come From? Radiocarbon dating relies on a simple natural phenomenon. As the Earth's upper atmosphere is bombarded by cosmic radiation, atmospheric nitrogen is broken down into an unstable isotope of carbon - carbon 14 (C-14). Bombardment Reactions The unstable isotope is brought to Earth by atmospheric activity, such as storms, and becomes fixed in the biosphere. Because it reacts identically to C-12 and C-13, C-14 becomes attached to complex organic molecules through photosynthesis in plants and becomes part of their molecular makeup. Animals eating those plants in turn absorb Carbon-14 as well as the stable isotopes. This process of ingesting C-14 continues as long as the plant or animal remains alive. Diffusion Ingestion C-14 Decay Profile The C-14 within an organism is continually decaying into stable carbon isotopes, but since the organism is absorbing more C-14 during its life, the ratio of C-14 to C-12 remains about the same as the ratio in the atmosphere. When the organism dies, the ratio of C-14 within its carcass begins to gradually decrease. The rate of decrease is 1/2 the quantity at death every 5,730 years. That is the half-life of C-14. The animation provides an example of how this logarithmic decay occurs. Click on the "Show Movie" button below to view this animation.

69. Quantum History - Carbon 14 Dating An AngloAmerican team found large variations in levels of the carbon-14 isotope, used as the basis of carbon dating, preserved in a 19in stalagmite recovered http://www.modomedia.com/quantum/carbondating.html

Facts, issues and accuracy A great deal of ancient history with regards to archaeology and orgins relies on results gained from Radiocarbon 14 dating. It is the attempt of this article to show explain the technique, and illustrate the "assumed component" as well as point out some of the clear and present risks in determining antiquity based upon this extremely commonly used measurement tool. Exposing the Issues This article does a far better job at illuminating the issues and assumptions regarding the carbon dating method than I could. I suggest it as a great primer for anyone who is interested in the validity of this dating method. Here is an excerpt and link: WHAT IS RADIOCARBON DATING AND IS IT A RELIABLE METHOD OF DATING ARCHAEOLOGICAL SITES? Many of us are intimidated by science. Radiocarbon dating, a development in atomic physics, is a case in point. The importance of this scientific method, however, is far reaching, influencing a multitude of various and independent disciplines such as hydrology, geology, atmospheric science and archaeology to name but a few. However, we leave the actual task of understanding radiocarbon dating to the boffin elite - we accept their conclusions blindly, respect the precision of their equipment and admire their genius. (click title for link) Marine Influence on Carbon Dating (from BBC website) Here is a rare quote from the BBC website that actually admits to error to radiocarbon dating, error which specifically has been noted to drastically INCREASE the age results. In this article, modern shellfish have been dated to find that they are 400 years old!

70. C-14 Debate From Alt.turin-shroud regain their statistical balance, the linen is enriched with carbon14, making its The beauty of radiocarbon dating is that there are two stable isotopes, 12C http://www.shroud.com/c14debat.htm

C-14 Debate from the Shroud Newsgroup: alt.turin-shroud Roger Sparks and William Meacham This article is compiled from a series of postings that appeared on the Shroud Newsgroup, alt.turin-shroud. In it, Rodger Sparks , a carbon dating expert from New Zealand, and William Meacham , archaeologist and Shroud researcher from Hong Kong, debated some of the theories that have been proposed regarding possible inaccuracies in the 1988 carbon dating test results. Subject: Re: C14 Dating of the Shroud From: "Rodger Sparks" Date: 1998/02/04 Newsgroups: alt.turin-shroud From: William Meacham Date: Wednesday, 28 January 1998 10:12 Subject: C14 Dating of the Shroud Anyone who still believes that C14 dating has proven the Shroud to be medieval should be quickly disabused of that notion. See the most recent report by Garza Valdes re-printed on www.shroud.com concerning "bio- plastic coating" he found on Shroud fibers, in sufficient quantity to throw the date WAY off. This organic material would of course be younger than the linen itself and would not have been removed in pretreatment. Let's start by noting that an organism growing on, and feeding on, the linen threads exclusively will simply re-shuffle the available carbon with no effect on the radiocarbon content. Hence the growth must incorporate carbon from an external source, and to produce an age shift like that postulated, that source must be the atmosphere, whether by photosynthesis or some other mechanism.

71. Dead Sea Scroll Dating determined by the carbon14 measurements, the Israel Antiquities Authority stated in a news release. ``The reliability of paleography as a dating method is http://packrat.aml.arizona.edu/deadsea.html

[The following is reprinted by permission from the Arizona Daily Star, UA confirms Dead Sea Scrolls predate Christianity By Jim Erickson The Arizona Daily Star UA researchers have carbon 14-dated bits of the Dead Sea Scrolls, and the results discredit the controversial theory that some of the texts may have been the work of early Christians. That theory was based in part on the contents of a scroll that University of Arizona researchers said was made before Christ was born. The scrolls consist of some 800 manuscripts in Hebrew and Aramaic that were discovered in caves east of Jerusalem, near the ruins of Qumran on the Dead Sea, between 1947 and 1956. They include the oldest known manuscripts of books from the Old Testament, and their discovery is considered one of the great archaeological finds of the century. Traditionally, the scrolls are viewed as the work of an ascetic Jewish sect, the Essenes, who lived in a monastery near the caves between about 200 B.C. and 100 A.D. ``But there is a school of thought that says that some of these scrolls - the Habakkuk in particular - refer to some Christian leader, maybe Christ or John the Baptist,'' said UA researcher A.J. Timothy Jull.

72. Encyclopedia: Carbon 14 Dating Updated Mar 05, 2004. Encyclopedia Carbon 14 dating. Radiocarbon dating is the use of a naturally occurring isotope of carbon in http://www.nationmaster.com/encyclopedia/Carbon-14-dating

Supporter Benefits Signup Login Sources ... Pies Factoid #46 Swedes and Norweigans rank top 5 for both providing aid and exporting weapons Interesting Facts Make your own graph: Hold down Control and click on several. Compare All Top 5 Top 10 Top 20 Top 100 Bottom 100 Bottom 20 Bottom 10 Bottom 5 All (desc) in category: Select Category Agriculture Crime Currency Democracy Economy Education Energy Environment Food Geography Government Health Identification Immigration Internet Labor Language Manufacturing Media Military Mortality People Religion Sports Taxation Transportation Welfare with statistic: view: Correlations Printable graph / table Pie chart Scatterplot with ... * Asterisk means graphable. Added May 21 Mortality stats Half price sale Catholic stats Top Graphs Richest Most Murderous Most Populous Most Militaristic ... More Stats Categories Agriculture Background Crime Currency ... Welfare Updated: , Encyclopedia : Carbon 14 dating Sorry, no entry exists for this yet. The Wikipedia article included on this page is licensed under the GFDL Usage implies agreement with terms

73. Creation Bits Number 23 What is carbon14? Carbon is an element that is required for life. Since there s very little 13 C, we ll ignore it in this discussion of dating. http://www.rae.org/bits23.htm

CREATION BITS No 23. Carbon-14 and the Age of the Earth Author: Curt Sewell Subject: Creation Overviews Date: Curt Sewell is the author of God at Ground Zero Essays by Author Essays by Subject Essays by Date What is Carbon-14? C or C), which are both stable, but a tiny fraction is C, which is radioactive, releasing a weak beta particle. The radioactive half-life for this emission is 5,730 years. Since there's very little C, we'll ignore it in this discussion of dating. from the atmosphere, absorb sunlight, and undergo photosynthesis the carbon is used as food to cause the plant to grow, while the oxygen is released back into the atmosphere. as waste. In this way, both plants and animals are constantly exchanging carbon and oxygen with that in the atmosphere. While they are alive, their bodies contain the same fraction of the three carbon isotopes as does the atmosphere, but at death, respiration ceases and the exchange stops. Since C constantly decays (with a 5,730-year half-life), the fraction of C in a dead body is always diminishing. After 5,730 years, the fraction of

74. The Straight Dope Mailbag: The Straight Dope Mailbag: How Does Carbon-14 Dating mass of 14) into the unstable radioactive iostope carbon14. the amounts of carbon-12 and carbon14 in the First hurdle carbon dating is only effective on http://www.straightdope.com/mailbag/mcarbon14.html

Home Page Message Boards News Archive ... FAQs, etc. From Cecil's Mailbag by the Straight Dope Science Advisory Board How does carbon-14 dating work? 02-Oct-2000 Dear Straight Dope: Hey, what I can't figure out is carbon dating. They can carbon date the Shroud of Turin, and realize it wasn't made 2,000 years ago, right? Well, before it was shroud, it was, like, wool or something, and before it was wool or somethnig, it was hairs on a sheep's back, right? Blah, blah, blah (you can see where I'm going with this). So at what point does something's carbon b-day start? Am I missing the point entirely here? I need your help, man. Randy SDSTAFF Ken replies: The broad principles behind carbon dating are fairly simple to explain. Look at your standard periodic table. Carbon is element 6, with an atomic mass of 12. Sunlight (cosmic radiation) strikes the upper atmosphere and converts a small amount of nitrogen (element 7, atomic mass of 14) into the unstable radioactive iostope carbon-14. The C-14 then gets bound into carbon dioxide gas molecules in the atmosphere, and thus absorbed into plant life. The plants are consumed by animals, and thus C-14 appears in all living creatures on Earth. When an organism dies, the C-14 in its cells is no longer replenished and so begins to decay, to revert back to nitrogen, at a constant, measurable rate. The half-life is about 5730 years. Therefore, we need only count the amounts of carbon-12 and carbon14 in the organic material, and compare the results, and voila! we have an initial estimate of the agethat is, the point at which the organism stopped absorbing C-14.

75. Did Scientists Fail Us? Carbon 14 And The Shroud Of Turin Reconsidering the Carbon 14 dating of the Shroud of Turin. One would have thought that any interest in the Shroud of Turin would http://www.historicaljesusquest.com/carbon-14.htm

Reconsidering the Carbon 14 Dating of the Shroud of Turin One would have thought that any interest in the Shroud of Turin would have quickly abated following the carbon 14 testing in 1988. According to the test results, it was not, as so many believed, the authentic burial Shroud of Jesus. It was medieval. Nature , the prestigious international weekly journal of science, published an article about the tests, coauthored by twenty-one scientists from the University of Oxford, the University of Arizona, the Institut f¼r Mittelenergiephysik in Zurich, Columbia University, and the British Museum. The conclusion in Nature was clear: The results of radiocarbon measurements at Arizona, Oxford and Zurich yield a calibrated calendar age range with at least 95 confidence for the linen of the Shroud of Turin of AD 1260 - 1390 (rounded down/up to nearest 10 yr). These results therefore provide conclusive evidence that the linen of the Shroud of Turin is mediaeval. A headline in the New York Times read: “Test Shows Shroud of Turin to be Fraud.” Other newspapers around the world reported similar conclusions. One of the radiocarbon dating scientists from Oxford stated on public television: “We have shown the Shroud to be a fake. Anyone who disagrees with us ought to belong to the Flat Earth Society.”

76. Carbon Dating carbon14 is used for a dating material because once it has been formed, C14 begins to decay radioactively back to nitrogen-14, at a rate of change that can be http://www.creationevidence.org/scientific_evid/carbon/se_carbon.html

Creation Science Briefs Subject: Carbon Dating A less-common form of the carbon atom, carbon-14, is used today by scientists as a method to date once-living organisms. Many people believe that carbon dating disproves the Biblical time scale of history. However, because of the difficulties with current C14 dating techniques, the dates produced have been shown to be faulty. CEM Staff Coal:Evidence/Young Earth Evidence for Creation Magnetic Field Created Earth ... www.creationevidence.org

77. The Method acid test of the new method was based upon radiocarbon dating of known The activity ratio relates to the carbon 14 activity ratio between the ancient samples http://www.c14dating.com/int.html

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

78. Radiocarbon Web-Info Radiocarbon WebInfo This resource contains reference materials on the radiocarbon dating method. Beginning with a summarization of the method, descriptions of three principal means of measuring http://rdre1.inktomi.com/click?u=http://www.c14dating.com/index.html&y=02653

79. Radiocarbon WEB-info Welcome to radiocarbon WEBinfo. Radiocarbon dating is the technique upon which chronologies of the late Pleistocene and Holocene have been built. http://www.c14dating.com/

Welcome to radiocarbon WEB-info. Radiocarbon dating is the technique upon which chronologies of the late Pleistocene and Holocene have been built. This resource is designed to provide online information concerning the radiocarbon dating method. We hope it will be of occasional use to radiocarbon users and interested students alike. thomas.higham@archaeology-research.oxford.ac.uk INDEX Introduction Measurement Applications WWW Links ... Email LAST MODIFIED 16 May 2002 HTML DOCUMENT BY T. HIGHAM.

80. Carbon 14 Dating Carbon 14 dating. Creation Position either as stable carbon 12 or unstable carbon 14. Carbon 14 is formed from ordinary nitrogen 14 in the atmosphere http://www.fsteiger.com/carbon14.html

Carbon 14 Dating 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.

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