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Radiometric Dating - Wikipedia, The Free Encyclopedia
radiometric dating (often called radioactive dating) is a technique used to date materials, usually based on a comparison between the observed abundance of
http://en.wikipedia.org/wiki/Radiometric_dating

Extractions: Jump to: navigation search Radiometric dating (often called radioactive dating ) is a technique used to date materials, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates. It is the principal source of information about the absolute age of rocks and other geological features, including the age of the Earth itself, and can be used to date a wide range of natural and man-made materials. Among the best-known techniques are radiocarbon dating potassium-argon dating and uranium-lead dating . By allowing the establishment of geological timescales, it provides a significant source of information about the ages of fossils and the deduced rates of evolutionary change. Radiometric dating is also used to date archaeological materials, including ancient artifacts. Different methods of radiometric dating vary in the timescale over which they are accurate and the materials to which they can be applied. All ordinary matter is made up of combinations of chemical elements , each with its own atomic number , indicating the number of protons in the atomic nucleus . Additionally, elements may exist in different
Radiometric Dating
Presents a broad overview of radiometric dating techniques and refutes various misconceptions held by Christians who doubt these methods because they
http://www.asa3.org/aSA/resources/Wiens.html

Extractions: RCWiens@MSN.Com [A PDF version of this document is also available.] First edition 1994; revised version 2002. Radiometric datingthe process of determining the age of rocks from the decay of their radioactive elementshas been in widespread use for over half a century. There are over forty such techniques, each using a different radioactive element or a different way of measuring them. It has become increasingly clear that these radiometric dating techniques agree with each other and as a whole, present a coherent picture in which the Earth was created a very long time ago. Further evidence comes from the complete agreement between radiometric dates and other dating methods such as counting tree rings or glacier ice core layers. Many Christians have been led to distrust radiometric dating and are completely unaware of the great number of laboratory measurements that have shown these methods to be consistent. Many are also unaware that Bible-believing Christians are among those actively involved in radiometric dating. This paper describes in relatively simple terms how a number of the dating techniques work, how accurately the half-lives of the radioactive elements and the rock dates themselves are known, and how dates are checked with one another. In the process the paper refutes a number of misconceptions prevalent among Christians today. This paper is available on the web via the American Scientific Affiliation and related sites to promote greater understanding and wisdom on this issue, particularly within the Christian community.
Radiometric Dating
Principles of radiometric dating. Naturallyoccurring radioactive materials break down into other materials at known rates. This is known as radioactive
http://www.gpc.edu/~pgore/geology/geo102/radio.htm

Extractions: Quantify the date in years. 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 urnanite 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 elemtns 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: In the above table, note that the number is the
Geologic Time: Radiometric Time Scale
Discusses the uses of limitations of different radiometric dating techniques.
http://pubs.usgs.gov/gip/geotime/radiometric.html

Extractions: The discovery of the natural radioactive decay of uranium in 1896 by Henry Becquerel, the French physicist, opened new vistas in science. In 1905, the British physicist Lord Rutherfordafter defining the structure of the atom made the first clear suggestion for using radioactivity as a tool for measuring geologic time directly; shortly thereafter, in 1907, Professor B. B. Boltwood, radiochemist of Yale Uniyersity, published a list of geologic ages based on radioactivity. Although Boltwood's ages have since been revised, they did show correctly that the duration of geologic time would be measured in terms of hundreds-to-thousands of millions of years. A technician of the U.S. Geological Survey uses a mass spectrometer to determine the proportions of neodymium isotopes contained in a sample of igneous rock. The next 40 years was a period of expanding research on the nature and behavior of atoms, leading to the development of nuclear fission and fusion as energy sources. A byproduct of this atomic research has been the development and continuing refinement of the various methods and techniques used to measure the age of Earth materials. Precise dating has been accomplished since 1950. A chemical element consists of atoms with a specific number of protons in their nuclei but different atomic weights owing to variations in the number of neutrons. Atoms of the same element with differing atomic weights are called isotopes. Radioactive decay is a spontaneous process in which an isotope (the parent) loses particles from its nucleus to form an isotope of a new element (the daughter). The rate of decay is conveniently expressed in terms of an isotope's half-life, or the time it takes for one-half of a particular radioactive isotope in a sample to decay. Most radioactive isotopes have rapid rates of decay (that is, short half-lives) and lose their radioactivity within a few days or years. Some isotopes, however, decay slowly, and several of these are used as geologic clocks. The parent isotopes and corresponding daughter products most commonly used to determine the ages of ancient rocks are listed below:
Radiometric Dating
www.dc.peachnet.edu/~pgore/geology/geo102/radio.htm Similar pages radiometric datingradiometric dating - A questionable method for establishing the old age of rocks. The unreliable basis for the Geologic Time Scale of earth.
http://www.dc.peachnet.edu/~pgore/geology/geo102/radio.htm
A Radiometric Dating Resource List
Large annotated directory of internet resources on radiocarbon and other radioactive dating methods, including creationists views and scientific critiques
http://www.tim-thompson.com/radiometric.html

Extractions: A Radiometric Dating Resource List The real heart of the age-of-the-earth debate (if "debate" is the right word) is always radiometric dating. There are lots of ways to guesstimate ages, and geologists knew the earth was old a long time ago (and I might add that they were mostly Christian creationist geologists). But they didn't know how old . Radiometric dating actually allows the measurement of absolute ages, and so it is deadly to the argument that the earth cannot be more than 10,000 years old. Radiometric methods measure the time elapsed since the particular radiometric clock was reset. Radiocarbon dating, which is probably best known in the general public, works only on things that were once alive and are now dead. It measures the time elapsed since death, but is limited in scale to no more than about 50,000 years ago. Other methods, such as Uranium/Lead, Potassium/Argon, Argon/Argon and others, are able to measure much longer time periods, and are not restricted to things that were once alive. Generally applied to igneous rocks (those of volcanic origin), they measure the time since the molten rock solidified. If that happens to be longer than 10,000 years, then the idea of a young-Earth is called into question. If that happens to be billions of years, then the young-Earth is in big trouble. Priscoan (4.00-4.03 Ga) orthogneisses from northwestern Canada
Get Answers: Radiometric Dating Methods
Answers to questions about radiometric dating from a creationist point of view.
http://www.answersingenesis.org/Home/area/faq/dating.asp

Extractions: answersingenesis.org has a new look NEW Answers Book (The) Thousands Not Billions Mythology of Modern Dating Methods (The) Radioisotopes and the Age of the Earth, Vol. 1 ... Geologic Evidences for Very Rapid Strata Deposition in the Grand Canyon Alien/UFOs Apologetics Archaeology Arguments NOT to use Bible Biographies - Creationists Cloning Countering the Critics Created Kinds Creation Compromises Creation: Why It Matters Darwin, Charles Death and Suffering Design Features Dinosaurs Education Embryonic Recapitulation Environmentalism Flood Fossils Geocentrism Genesis Genetics Geology God History Human Life: Abortion Ice Age Information Theory Jesus Christ Linguistics Living Fossils Mammoths Morality and Ethics Mutations Natural Selection Origin of Life Philosophy Plate Tectonics Probabilities Racism Radiometric Dating Religion (humanism, etc.)
Evolution: Library: Radiometric Dating
Geologist Ralph Harvey and historian Mott Greene explain the principles of radiometric dating and its application in determining the age of Earth.
http://www.pbs.org/wgbh/evolution/library/03/3/l_033_01.html

Extractions: var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www."); document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E")); Geologist Ralph Harvey and historian Mott Greene explain the principles of radiometric dating and its application in determining the age of Earth. As the uranium in rocks decays, it emits subatomic particles and turns into lead at a constant rate. Measuring the uranium-to-lead ratios in the oldest rocks on Earth gave scientists an estimated age of the planet of 4.6 billion years. Segment from A Science Odyssey: "Origins." Credits: View in: It turns out the answers are in Earth's rocks. Even the Greeks and Romans realized that layers of sediment in rock signified old age. But it wasn't until the late 1700s when Scottish geologist James Hutton, who observed sediments building up on the landscape, set out to show that rocks were time clocks that serious scientific interest in geological age began. Before then, the Bible had provided the only estimate for the age of the world: about 6,000 years, with Genesis as the history book.
Radiometric Dating And The Geological Time Scale
This document discusses the way radiometric dating and stratigraphic principles are used to establish the conventional geological time scale.
http://www.talkorigins.org/faqs/dating.html

Extractions: [Links updated: September 12, 2004] Other Links: his document discusses the way radiometric dating and stratigraphic principles are used to establish the conventional geological time scale. It is not about the theory behind radiometric dating methods, it is about their application , and it therefore assumes the reader has some familiarity with the technique already (refer to "Other Sources" for more information). As an example of how they are used, radiometric dates from geologically simple, fossiliferous Cretaceous rocks in western North America are compared to the geological time scale. To get to that point, there is also a historical discussion and description of non-radiometric dating methods. The example used here contrasts sharply with the way conventional scientific dating methods are characterized by some critics (for example, refer to discussion in "
Age Of The Earth
The more I learn about radiometric dating, the more I appreciate the quality of All of the above data are from G. Brent Dalrymple, radiometric dating,
http://www.gate.net/~rwms/AgeEarth.html

Extractions: from The Evolution Evidence Page Scientists have settled on the age of the earth of about 4.6 billion years as a result of research started almost 50 years ago. This conclusion was based upon carefully designed and conducted experiments that compared the ratios in rock samples of parent elements to daughter elements ( some of which would have been from radioactive decay of the parent, some of which may have been present in the sample at the time of formation). Since radioactive decay is known to occur at a constant rate, the age of a rock can be determined from the ratio of the parent element to the daughter element. The concerns about these dating methods were exactly the same that creationists continue to raise - presence of the daughter element at the time the rock was formed and possible loss / gain of either the parent or daughter element at some point in the history of the rock. For this reason, the tests were designed to account for those possibilities. The other problem to avoid when dating rocks is the possibility that changes to the rock have caused loss or gain of either the parent or daughter element - this would lead to a false date (too old if parent element were lost, too young if daughter element were lost). I know of two methods that have been designed that can account for this possibility - isochron dating and the uranium-thorium-lead discordia / concordia method (actually three independent age calculations for one sample). Both of these methods have internal checks for the possible loss / gain of elements to the rock.
- Radiometric Dating Game -
Evolutionists claim radiometric dating supports their claims of a multimillion-year history of macro-evolution. They re lying.
http://www.trueorigin.org/dating.asp

Extractions: Home Feedback Links Books David Plaisted Dr. Plaisted responds to comments and criticisms of this article here However, this causes a problem for those who believe based on the Bible that life has only existed on the earth for a few thousand years, since fossils are found in rocks that are dated to be over 500 million years old by radiometric methods, and some fossils are found in rocks that are dated to be billions of years old. If these dates are correct, this calls the Biblical account of a recent creation of life into question. After study and discussion of this question, I now believe that the claimed accuracy of radiometric dating methods is a result of a great misunderstanding of the data, and that the various methods hardly ever agree with each other, and often do not agree with the assumed ages of the rocks in which they are found. I believe that there is a great need for this information to be made known, so I am making this article available in the hopes that it will enlighten others who are considering these questions. Even the creationist accounts that I have read do not adequately treat these issues. At the start, let me clarify that my main concern is not the age of the earth, the moon, or the solar system, but rather the age of life, that is, how long has life existed on earth. Many dating methods seem to give about the same ages on meteorites. Thus radiometric dating methods appear to give evidence that the earth and meteorites are old, if one accepts the fact that decay rates have been constant. However, there may be other explanations for this apparent age. Perhaps the earth was made from older pre-existing matter, or perhaps decay rates were briefly faster for some reason. When one considers the power of God, one sees that any such conclusions are to some extent tentative. For some evidence for a young universe, see
The Radiometric Dating Game
A set of links to articles on radiometric dating, especially those which state that it is inaccurate.
http://www.cs.unc.edu/~plaisted/ce/dating.html

Extractions: The sections on the branching ratio and dating meteorites need updating.) However, this causes a problem for those who believe based on the Bible that life has only existed on the earth for a few thousand years, since fossils are found in rocks that are dated to be over 500 million years old by radiometric methods, and some fossils are found in rocks that are dated to be billions of years old. If these dates are correct, this calls the Biblical account of a recent creation of life into question. After study and discussion of this question, I now believe that the claimed accuracy of radiometric dating methods is a result of a great misunderstanding of the data, and that the various methods hardly ever agree with each other, and often do not agree with the assumed ages of the rocks in which they are found. I believe that there is a great need for this information to be made known, so I am making this article available in the hopes that it will enlighten others who are considering these questions. Even the creationist accounts that I have read do not adequately treat these issues. At the start, let me clarify that my main concern is not the age of the earth, the moon, or the solar system, but rather the age of life, that is, how long has life existed on earth. Many dating methods seem to give about the same ages on meteorites. Thus radiometric dating methods appear to give evidence that the earth and meteorites are old, if one accepts the fact that decay rates have been constant. However, there may be other explanations for this apparent age. Perhaps the earth was made from older pre-existing matter, or perhaps decay rates were briefly faster for some reason. When one considers the power of God, one sees that any such conclusions are to some extent tentative. For some evidence for a young universe, see
Radiometric Dating
radiometric dating is a means of determining the age of a mineral specimen by determining the relative amounts present of certain radioactive elements.
http://www.holysmoke.org/cretins/chrono.htm

Extractions: Radiometric dating is a means of determining the "age" of a mineral specimen by determining the relative amounts present of certain radioactive elements. By "age" we mean the elapsed time from when the mineral specimen was formed. Radioactive elements "decay" (that is, change into other elements) by "half lives." If a half life is equal to one year, then one half of the radioactive element will have decayed in the first year after the mineral was formed; one half of the remainder will decay in the next year (leaving one-fourth remaining), and so forth. The formula for the fraction remaining is one-half raised to the power given by the number of years divided by the half-life (in other words raised to a power equal to the number of half-lives). If we knew the fraction of a radioactive element still remaining in a mineral, it would be a simple matter to calculate its age by the formula log F = N/Hlog(1/2) (1) where: F = fraction remaining N = number of years and H = half life. To determine the fraction still remaining, we must know both the amount now present and also the amount present when the mineral was formed. Contrary to creationist claims, it is possible to make that determination, as the following will explain:
Radiometric Dating: Clair Patterson
Age of rock layers established using radiometric dating Scientists measure the ages of rock layers on Earth using radiometric dating.
http://evolution.berkeley.edu/evolibrary/article//history_23

Extractions: At the dawn of the twentieth century, physicists made a revolutionary discovery: elements are not eternal. Atoms can fuse together to create new elements; they can also spontaneously break down, firing off subatomic particles and switching from one element to another in the process (see figure, right). While some physicists used these discoveries for applications ranging from nuclear weapons to nuclear medicine, others applied them to understanding the natural world. The sun was once thought to burn like a coal fire, but physicists showed that it actually generates energy by slamming atoms together and creating new elements. The primordial cloud of dust that came to form the Earth contained unstable atoms, known as radioactive isotopes. Since its birth, these isotopes have been breaking down and releasing energy that adds heat to the planet's interior.
TWD -- Radiometric Dating
An article that explains the basic science behind radiometric dating techniques, and defends it from creationist attacks.
http://www.jwoolfden.com/rad_dat.html

Extractions: Radiometric Dating When I first got involved in the creationism/evolution controversy, in 1995 or thereabouts, I looked around for an article or book that explained radiometric dating in a way that nonscientists could understand. I couldn't find one. So I set out to write one. This article was the result. Radiometric dating methods are the strongest direct evidence that geologists have for the age of the Earth. All these methods point to Earth being very, very old several billions of years old. Young-Earth creationists that is, creationists who believe that Earth is no more than 10,000 years old are fond of attacking radiometric dating methods as being full of inaccuracies and riddled with sources of error. When I first became interested in the creation-evolution debate, in late 1994, I looked around for sources that clearly and simply explained what radiometric dating is and why young-Earth creationists are driven to discredit it. I found several good sources, but none that seemed both complete enough to stand alone and simple enough for a nongeologist to understand them. Thus this essay, which is my attempt at producing such a source.
Radiometric Dating
Principles of radiometric dating. Radioactive decay is described in terms of the probability that a constituent particle of the nucleus of an atom will
http://www.tulane.edu/~sanelson/eens211/radiometric_dating.htm

Extractions: EENS 211 Earth Materials Tulane University Prof. Stephen A. Nelson Radiometric Dating Prior to 1905 the best and most accepted age of the Earth was that proposed by Lord Kelvin based on the amount of time necessary for the Earth to cool to its present temperature from a completely liquid state. Although we now recognize lots of problems with that calculation, the age of 25 my was accepted by most physicists, but considered too short by most geologists. Then, in 1896, radioactivity was discovered. Recognition that radioactive decay of atoms occurs in the Earth was important in two respects: It provided another source of heat, not considered by Kelvin, which would mean that the cooling time would have to be much longer. Principles of Radiometric Dating Radioactive decay is described in terms of the probability that a constituent particle of the nucleus of an atom will escape through the potential (Energy) barrier which bonds them to the nucleus. The energies involved are so large, and the nucleus is so small that physical conditions in the Earth (i.e. T and P) cannot affect the rate of decay. The rate of decay or rate of change of the number N of particles is proportional to the number present at any time, i.e.
Untitled Document
This handson activity is a simulation of some of the radiometric dating techniques used by scientists to determine the age of a mineral or fossil.
http://www.acad.carleton.edu/curricular/BIOL/classes/bio302/Pages/Half-life.html

Extractions: Radiometric Dating Activity This hands-on activity is a simulation of some of the radiometric dating techniques used by scientists to determine the age of a mineral or fossil. The activity uses the basic principle of radioactive half-life, and is a good follow-up lesson after the students have learned about half-life properties. See the background information on radioactive half-life and carbon dating for more details on these subjects Objective: Students will use half-life properties of isotopes to determine the age of different "rocks" and "fossils" made out of bags of beads. Through this simulation, they will gain an understanding of how scientists are able to use isotopes such as U-235 and Pb-207 to determine the age of ancient minerals. National Science Education Standards : Grades 5-8: CONTENT STANDARD A (Science as Inquiry): Mathematics is important in all aspects of scientific inquiry. CONTENT STANDARD E (Science and Technology): Science and technology are reciprocal. Science helps drive technology, as it addresses questions that demand more sophisticated instruments and provides principles for better instrumentation and technique. Technology is essential to science, because it provides instruments and techniques that enable observations of objects and phenomena that are otherwise unobservable due to factors such as quantity, distance, location, size, and speed. Technology also provides tools for investigations, inquiry, and analysis.
Radiometric Dating Methods
There is, of course, one radiometric dating method that appears to overcome the vital zero date problem . The isochron dating method theoretically
http://naturalselection.0catch.com/Files/radiometricdating.html

Extractions: Radiometric Dating Methods Sean D. Pitman M.D. July 2004 History of Radiometric Dating Potassium 40 Argon 40 1.25 billion yrs Rubidium 87 Strontium 87 48.8 billion yrs Thorium 232 Lead 208 14 billion years Uranium 235 Lead 207 704 million years Uranium 238 Lead 206 4.47 billion years Carbon 14 Nitrogen 14 5730 years The radioactivity of is unusual, in that two processes take place: b-decay: electron capture: 11.2% At the time that Darwin's On the Origin of Species was published, the earth was "scientifically" determined to be 100 million years old. By 1932, it was found to be 1.6 billion years old. In 1947, science firmly established that the earth was 3.4 billion years old. Finally in 1976, it was discovered that the earth is "really" 4.6 billion years old What happened? The study of geology grew out of field studies associated with mining and engineering during the sixteenth to nineteenth centuries.
USGS Geology In The Parks
A commonly used radiometric dating technique relies on the breakdown of radiometric dating has been used to determine the ages of the Earth, Moon,
http://wrgis.wr.usgs.gov/parks/gtime/radiom.html

Extractions: Radioactive elements were incorporated into the Earth when the Solar System formed. All rocks and minerals contain tiny amounts of these radioactive elements. Radioactive elements are unstable; they breakdown spontaneously into more stable atoms over time, a process known as radioactive decay. Radioactive decay occurs at a constant rate, specific to each radioactive isotope Radiometric clocks are "set" when each rock forms. "Forms" means the moment an igneous rock solidifies from magma, a sedimentary rock layer is deposited, or a rock heated by metamorphism cools off. It's this resetting process that gives us the ability to date rocks that formed at different times in earth history. A commonly used radiometric dating technique relies on the breakdown of potassium ( K) to argon ( Ar). In igneous rocks, the potassium-argon "clock" is set the moment the rock first crystallizes from magma. Precise measurements of the amount of P relative to Ar in an igneous rock can tell us the amount of time that has passed since the rock crystallized. If an igneous or other rock is metamorphosed, its radiometric clock is reset, and potassium-argon measurements can be used to tell the number of years that has passed since metamorphism.
Radiometric Dating | Amazing Discoveries
radiometric dating techniques are thus based on sound scientific principles, but rely on so many basic assumptions that the Biblebelieving student need not
http://amazingdiscoveries.org/radiometric-dating.html

Extractions: DidYouKnow "Many people are under the impression that "Evolution" is a science. In their minds they view evolution as no different than geology, biology or physics. Evolution however is a belief system or theory that is based on an interpretation of scientific evidence. Amazing Discoveries presents some of the common examples used to prove evolution and lets you see what the evidence really shows." Amazing Discoveries Testimony "Thank you Dr. Veith for all of your knowledge and sharing of your faith with fellow believers. You are inspiring and very informative. Please keep it up. May we keep strong until the end and keep God number 1. Jeremy V." Jeremy V.

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