61. Radiometric Dating radiometric dating. Pamela JW Gore Georgia Perimeter College. How do we determine the age of a rock? radiometric dating. Principles of radiometric dating. http://gpc.edu/~pgore/geology/historical_lecture/radio.htm

Radiometric Dating Pamela J. W. Gore Georgia Perimeter College How do we determine the age of a rock? Relative dating - Steno's Laws, etc. "A is older than B" Absolute dating Quantify the date in years. Radiometric Dating Principles of Radiometric Dating Naturally-occurring radioactive materials break down into other materials at known rates. This is known as radioactive decay Radioactive parent elements decay to stable daughter elements. Radioactivity was discovered in 1896 by Henri Becquerel. In 1905, Rutherford and Boltwood used the principle of radioactive decay to measure the age of rocks and minerals (using Uranium decaying to produce Helium. In 1907, Boltwood dated a sample of urananite based on uranium/lead ratios. Amazingly, this was all done before isotopes were known, and before the decay rates were known accurately. The invention of the MASS SPECTROMETER after World War I (post-1918) led to the discovery of more than 200 isotopes. Many radioactive elements can be used as geologic clocks. Each radioactive element decays at its own nearly constant rate. Once this rate is known, geologists can estimate the length of time over which decay has been occurring by measuring the amount of radioactive parent element and the amount of stable daughter elements Examples: Radioactive parent isotopes and their stable daughter products Radioactive Parent Stable Daughter Potassium 40 Argon 40 Rubidium 87 Strontium 87 Thorium 232 Lead 208 Uranium 235 Lead 207 Uranium 238

62. Radiometric Dating - Encyclopedia Article About Radiometric Dating. Free Access, encyclopedia article about radiometric dating. radiometric dating in Free online English dictionary, thesaurus and encyclopedia. radiometric dating. http://encyclopedia.thefreedictionary.com/Radiometric dating

Dictionaries: General Computing Medical Legal Encyclopedia Radiometric dating Word: Word Starts with Ends with Definition Radiometric dating is the determination of the date at which materials were formed by analyzing the decay of radioactive isotopes that were incorporated into the material when it was created and which presumably have not diffused out. The most common form of radiometric dating is radiocarbon dating Radiocarbon dating is the use of a naturally occurring isotope of carbon in radiometric dating to determine the age of organic materials. Carbon has two stable isotopes: carbon-12 ( C), and carbon-13 ( C). In addition, there are tiny amounts of the unstable (radioactive) isotope carbon-14 ( C) on earth. C has a half-life of just under 6000 years, and so would have long ago vanished from the earth, were it not for its constant formation by cosmic ray impacts on nitrogen in the earth's atmosphere. When cosmic rays enter the atmosphere they undergo various transformations, including the production of neutrons. The resulting neutrons participate in the following reaction: Click the link for more information.

63. Bad News For Radiometric Dating [Free Republic] radiometric dating Geochronology Geology Earth SciencesEarth Sciences. Most comprehensive resource on Earth Sciences Geology Geochronology radiometric dating. Rate Radioactive Dating 5. radiometric dating . http://www.freerepublic.com/forum/a3921cfc5772d.htm

FreeRepublic .com "A Conservative News Forum" Last ... Culture/Society News Keywords: RADIOMETRIC DATING FLAWED Source: David Plaisted Website Author: David Plaisted Posted on 05/16/2000 15:46:29 PDT by knowquest Most scientists today believe that life has existed on the earth for billions of years. This belief in long ages for the earth and the existence of life is derived largely from radiometric dating. These long time periods are computed by measuring the ratio of daughter to parent substance in a rock and inferring an age based on this ratio. This age is computed under the assumption that the parent substance (say, uranium) gradually decays to the daughter substance (say, lead), so the higher the ratio of lead to uranium, the older the rock must be. Of course, there are many problems with such dating methods, such as parent or daughter substances entering or leaving the rock, as well as daughter product being present at the beginning. Here I want to concentrate on another source of error, namely, processes that take place within magma chambers. To me it has been a real eye opener to see all the processes that are taking place and their potential influence on radiometric dating. Radiometric dating is largely done on rock that has formed from solidified lava. Lava (properly called magma before it erupts) fills large underground chambers called magma chambers. Most people are not aware of the many processes that take place in lava before it erupts and as it solidifies, processes that can have a tremendous influence on daughter to parent ratios. Such processes can cause the daughter product to be enriched relative to the parent, which would make the rock look older, or cause the parent to be enriched relative to the daughter, which would make the rock look younger. This calls the whole radiometric dating scheme into serious question.

64. Geol 02C Historical Geology - Radiometric Dating Geol 02C Historical Geology J Bret Bennington. radiometric dating of the Rock Record. Determining Absolute Ages. radiometric dating. http://people.hofstra.edu/hu/faculty/bret_bennington/2cnotes/dating.html

Geol 02C Historical Geology J Bret Bennington Radiometric Dating of the Rock Record Determining Absolute Ages Absolute ages are direct measurements of the age of a rock in years, as opposed to a relative age that simply puts rock layers in time order. Radiometric Dating Shortly after the discovery in 1895 that certain radioactive atoms decay spontaneously through the emission of high energy particles into different non-radioactive atoms, scientists realized that this could provide a method for determining the absolute age of certain rocks. The key to radiometric dating is the fact that radioactive elements all have a distinct and unchanging half life Radioactive decay Radioactive decay is a stochastic process - it is impossible to predict when exactly a single individual atom will decay, but there is a finite and measurable probability that a certain percentage of a large population of them will decay over a period of time. Half lives The half life is defined as the time it take one half of the present radioactive atoms to decay. The radioactive element is called a radioisotope or parent isotope and the non-radioactive end product of decay is called a daughter isotope . Half lives are physical constants that depend only on the type of atom decaying. Half life values appear to be unaffected by temperature, pressure, presence of other atoms, etc. They are a fundamental property of the forces that hold together the atomic nucleus.

65. Radiometric Dating radiometric dating. 12/2/03. Click here to start. Table of Contents. radiometric dating. Poor Lord Kelvin. . . Not only does the http://faculty.uca.edu/~benw/sci3410/pres/radiometrics/

Radiometric Dating Click here to start Table of Contents Radiometric Dating Poor Lord Kelvin. . . Not only does the Earthís radioactivity keep the interior toasty warm, it provides a natural ìclockî for dating certain rocks. Half a life is better than none. . . . Half a life is better than none. . . . ... This diagram shows the sequence of rock layers in the East African Rift Valley, along with the curious fossils they contain. . . The tuffs (volcanic ash beds) have been datedó notice how the ones on top have younger dates than the ones below. Author: Ben Waggoner Email: benw@mail.uca.edu Home Page: http://faculty.uca.edu/~benw/sci3410/

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67. Earth.ics.uci.edu/faqs/dating.html Evolution Dating Methods Back to Page Index. radiometric dating Methods. radiometric dating A Christian Perspective by Dr. Roger C. Wiens, Los Alamos National Laboratory. http://earth.ics.uci.edu/faqs/dating.html

68. Scientists & Discovery, Radiometirc Dating, Museum Victoria, Australia. radiometric dating. radiometric dating is possible because the radioactive decay of large numbers of radioactive atoms follows a predictable pattern. http://www.museum.vic.gov.au/scidiscovery/radioactivity/radio_dating.asp

If the size of the text in this page is too small, please either turn javascript on or adjust the default text size of your browser. Radioactivity Fission and Fusion Radioactive Decay Radiometric Dating Applications of Radiation What is Radiation? Radioactivity Radiometric Dating ... printer friendly page Radiometric Dating Radioactive decay allows geologists and physicists to measure the age of ancient fossils, rocks and even the Earth. This process is called radiometric or radioactive dating. Radiometric dating is possible because the radioactive decay of large numbers of radioactive atoms follows a predictable pattern. This predictability allows scientists to measure the age of an object if they can work out how many radioactive atoms were originally present. Two situations where we can do this involve Potassium-40 atoms and Carbon-14 atoms. All radioactive atoms decay to become a more stable kind of atom. The original radioactive atom is known as a parent isotope, while the atom produced by the decay process is known as a daughter isotope. Isotopes are different forms of the same element. For example Uranium-235 and Uranium-238 are both Uranium atoms with the same number of protons, but they have a different number of neutrons. The number used to identify the isotope refers to the total number of particles in the nucleus of each atom.

69. Radiometric Dating Of The Siloam Tunnel, Jerusalem ERROR, There has been an error while processing your request. In most cases, this is an isolated incident that can be overcome by http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v425/n6954/abs/n

70. Evolution Happens Radiometric Dating Page APPENDIX Common Misconceptions Regarding radiometric dating Methods From “radiometric dating A Christian Perspective”, 2nd Edition, by Dr. Roger C. Wiens. http://www.evolutionhappens.net/radiometric.htm

APPENDIX: Common Misconceptions Regarding Radiometric Dating Methods From Radiometric Dating: A Christian Perspective , 2nd Edition, by Dr. Roger C. Wiens There are a number of misconceptions that seem especially prevalent among Christians. Most of these topics are covered in the paper at the link listed above, but they are reviewed briefly here for clarity. References below are to sections of the paper available on the web. Radiometric dating is based on index fossils whose dates were assigned long before radioactivity was discovered. This is not at all true, though it is implied by some young-Earth literature. Radiometric dating is based on the half-lives of the radioactive isotopes. These half-lives have been measured over the last 40-90 years. They are not calibrated by fossils. No one has measured the decay rates directly; we only know them from inference. Decay rates have been directly measured over the last 40-100 years. In some cases a batch of the pure parent material is weighed and then set aside for a long time and then the resulting daughter material is weighed. In many cases it is easier to detect radioactive decays by the energy burst that each decay gives off. For this a batch of the pure parent material is carefully weighed and then put in front of a Geiger counter or gamma-ray detector. These instruments count the number of decays over a long time. If the half-lives are billions of years, it is impossible to determine them from measuring over just a few years or decades.

71. Radiometric Dating Definition Meaning Information Explanation radiometric dating definition, meaning and explanation and more about radiometric dating. FreeDefinition - Online Glossary and Encyclopedia, radiometric dating. http://www.free-definition.com/Radiometric-dating.html

A B C D ... Contact Beta 0.71 powered by: akademie.de PHP PostgreSQL Google News about your search term Radiometric dating Radiometric dating is the determination of the date at which materials were formed by analyzing the decay of radioactive isotopes that were incorporated into the material when it was created and which presumably have not diffused out. Probably the best known form of radiometric dating is radiocarbon dating , which uses carbon -14. Rubidum-Strontium dating is also popular. Most materials decay radioactively to some extent, but the decay rates of most are so long that, for all practical purposes, they can be considered inert. The remainder are said to be radioactive . Radioactive materials can decay in any of several ways, emitting either a particle or radiation and changing to a different element or isotope. The decay rate of radioactive materials does not depend on temperature , chemical environment, or similar factors. For dating purposes, the important parameter is the half-life of the reaction - the time it takes for half the material to decay. Half lives of various isotopes vary from microseconds to billions of years. Materials useful for radiometric dating have half lives from a few thousand to a few billion years. Some types of radiometric dating assume that the initial proportions of a radioactive substance and its decay product are known. The decay product should not be a small-molecule gas that can leak out, and must itself have a long enough half life that it will be present in significant amounts. In addition, the initial element and the decay product should not be produced or depleted in significant amounts by other reactions. The procedures used to isolate and analyze the reaction products must be straightforward and reliable.

72. MSN Encarta - Dating Methods C. Obsidian Hydration Dating. D. Thermoluminescence (TL) Dating. E. radiometric dating. 1. Basic Theory. 2. Carbon14 Method. 3. Potassium-Argon Method. http://encarta.msn.com/encyclopedia_761554115/Dating_Methods.html

MSN Home My MSN Hotmail Shopping ... Money Web Search: logoImg('http://sc.msn.com'); Encarta Subscriber Sign In Help Home ... Upgrade to Encarta Premium Search Encarta Subscription Article MSN Encarta Premium: Get this article, plus 60,000 other articles, an interactive atlas, dictionaries, thesaurus, articles from 100 leading magazines, homework tools, daily math help and more for $4.95/month or $29.95/year (plus applicable taxes.) Learn more. This article is exclusively available for MSN Encarta Premium Subscribers. Already a subscriber? Sign in above. Dating Methods I. Introduction Dating Methods , in earth science, methods used to date the age of rocks and minerals. By applying this information, geologists are able to decipher the... II. Development of Relative and Absolute Methods III. Absolute Dating Methods A. Dendrochronology B. Varve Analysis C. Obsidian Hydration Dating D. Thermoluminescence (TL) Dating E. Radiometric Dating Basic Theory Carbon-14 Method Potassium-Argon Method Rubidium-Strontium Method Methods Involving Thorium-230 Methods Involving Lead Fission-Track Dating F.

73. Claim 1 - Radiometric Dating Is Inaccurate Claim 1 radiometric dating is Inaccurate. radiometric dating is one of the processes by which the age of the Earth has been determined. http://www.ast.cam.ac.uk/~cmf/evolution/claim1.html

Claim 1 - Radiometric Dating is Inaccurate Radiometric dating is one of the processes by which the age of the Earth has been determined. One example of which you might have heard is Carbon-14 dating, which is used for dating of biological samples such as bones. The principle for this technique is rather simple. Carbon-14 is produced at a reasonably constant rate in the upper atmosphere. Living animals have a known level of Carbon-14 in their bodies as they breathe it in all the time from the air. They also have other, stable varieties ("isotopes") of carbon, such as Carbon-12, which is far more common. In a living creature, the ratio of abundance of these two substances simply reflects that in the atmosphere, and is therefore well-known. If this animal then dies and therefore is not able to gather more Carbon-14 then the ratio of the two elements will start to change as the Carbon-14 decays into a more stable form, such as Carbon-12 or Carbon-13. This is known to happen with a half-life of about 5,700 years, which means that after 5,700 years, the amount of Carbon-14 in a sample should have decayed to approximately half its initial value. If we know the original proportions of Carbon-14 and Carbon-12, and we can measure their ratio at a later date then we can work out how much of the Carbon-14 has decayed, and hence we can calculate the age of the sample. Carbon-14 dating is typically used to date archaeological remains, especially from iron- and bronze-age sites of a few thousand years in age. Results are generally quoted to within 5 or 10 percent, and the ages thus obtained are usually in good agreement with the expected ages of the samples. Carbon-14 dating cannot be used to date remains older than about 50,000 years because the level of Carbon-14 in the sample will then be far too low for an accurate determination.

74. CMI Resources - Articles View Printable Version. The Faith of radiometric dating. By By Curt Sewell. Certainly the majority of scientists accept radiometric dating. http://www.creationmoments.com/resources/article.asp?art_id=65

75. Radiometric Dating Of Sedimentary Rocks How do you radiometrically date sedimentary rocks? Except for radiocarbon, most radiometric dating methods work on igneous or metamorphic rocks. http://seis.natsci.csulb.edu/rbehl/integration.htm

76. Radiometric Dating - InformationBlast radiometric dating Information Blast. radiometric dating. Materials useful for radiometric dating have half lives from a few thousand to a few billion years. http://www.informationblast.com/Radiometric_dating.html

Radiometric dating Radiometric dating is the determination of the date at which materials were formed by analyzing the decay of radioactive isotopes that were incorporated into the material when it was created and which presumably have not diffused out. The most common form of radiometric dating is radiocarbon dating , which is based on the decay of carbon -14 to carbon-12. Other types of radiometric dating include rubidium-strontium, samarium-neodymium, potassium-argon, argon-argon, uranium-thorium, and uranium-lead. These methods differ in accuracy, cost, and range of applicability. Most materials decay radioactively to some extent, but the decay rates of most are so long that, for all practical purposes, they can be considered inert. The remainder are said to be radioactive . Radiometric dating is based on forms of radioactive decay in which the atomic nucleus emits a neutron or alpha particle and becomes a different element or isotope . The decay rate of radioactive materials does not depend on temperature , chemical environment, or similar factors. For dating purposes, the important parameter is the

77. :: Ez2Find :: Radiometric Dating Guide radiometric dating, Guides, radiometric dating. ez2Find Home Directory Science Earth Sciences Geology Geochronology radiometric dating (5) http://ez2find.com/cgi-bin/directory/meta/search.pl/Science/Earth_Sciences/Geolo

Guide : Radiometric Dating Global Metasearch Any Language English Afrikaans Arabic Bahasa Melayu Belarusian Bulgarian Catala Chinese Simplified Chinese Traditional Cymraeg Czech Dansk Deutsch Eesti Espanol Euskara Faroese Francais Frysk Galego Greek Hebrew Hrvatski Indonesia Islenska Italiano Japanese Korean Latvian Lietuviu Lingua Latina Magyar Netherlands Norsk Polska Portugues Romana Russian Shqip Slovensko Slovensky Srpski Suomi Svenska Thai Turkce Ukrainian Vietnamese Mode All Words Any Word Phrase Results Timeout Depth Adult Filter Add to Favorites Other Search Web News Newsgroups Images Invisible Web Find romance at Yahoo! Personals I'm Man Female Seeking Female Man ZIP Age: to Guides Radiometric Dating ez2Find Home Directory Science Earth Sciences ... Geochronology : Radiometric Dating Radiocarbon Related Categories Science: Earth Sciences: Geochemistry Web Sites Radioactive Dating [Site Info] [Translate] [Open New Window] Simple explanation of the topic of radiometric age determination. URL: http://library.thinkquest.org/3471/radioactive_dating.html Radiometric Dating [Site Info] [Translate] [Open New Window] Educational materials on the topic. URL: http://www.dc.peachnet.edu/~pgore/geology/geo102/radio.htm

78. Science, Earth Sciences, Geology, Geochronology: Radiometric Dating A radiometric dating Resource List Large annotated directory of internet resources on radiocarbon and other radioactive dating methods, including creationists http://www.combose.com/Science/Earth_Sciences/Geology/Geochronology/Radiometric_

Top Science Earth Sciences Geology ... Radiocarbon Related links of interest: Science:Earth Sciences:Geochemistry A Radiometric Dating Resource List - Large annotated directory of internet resources on radiocarbon and other radioactive dating methods, including creationists' views and scientific critiques of those views. Radioactive Dating - Simple explanation of the topic or radiometric age determination. Radiometric Dating - Educational materials on the topic. Radiometric Time Scale - Discusses the uses of limitations of different radiometric dating techniques. Help build the largest human-edited directory on the web. Submit a Site Open Directory Project Become an Editor The combose.com directory is based on the Open Directory and has been modified and enhanced using our own technology. About ComboSE Download Combose Toolbar

79. Radiometric Dating: Radioactive Carbon, Potassium Argon, Uranium Lead radiometric dating explained. Overview of radiometric dating There is no instrument available to measure the age of any substance. http://www.eadshome.com/RadiometricDating.htm

Updated: Saturday, March 6, 2004 home "In the beginning..." Creation vs. Evolution How old is the earth? What about fossils? What about transitional forms? Radiometric Dating explained Overview of Radiometric Dating: There is no instrument available to measure the age of any substance. We can examine a rock, measure its composition and ratio of various elements, but we can never get a direct age. We must make assumptions based upon the chemical and mineral composition of a specimen before we can draw a conclusion about its age. These assumptions Uranium-Lead Dating: This dating method is used primarily on igneous rocks and is used to date objects thought to be quite old. Uranium-238 has a half-life of about 4.5 billion years. This means that if we could watch a sample of U-238 for 4.5 billion years, we would note that half of it would be gone, having decayed to Lead [Pb]-206. U-Pb dating is based upon three assumptions: 1) A constant decay rate this is a reasonable assumption based upon observed physical properties.

80. Advlearn.lrdc.pitt.edu/belvedere/materials/Mass-Extinctions/Radioact.htm radiometric dating Wikipedia PhatNav s Encyclopedia - A Wikipedia . radiometric dating. Probably the best known form of radiometric dating is radiocarbon dating, which uses carbon-14. http://advlearn.lrdc.pitt.edu/belvedere/materials/Mass-Extinctions/Radioact.htm

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