41. How Do Geologists Date Rocks? Radiometric Dating How do geologists date rocks? radiometric dating! A commonly used radiometric datingtechnique relies on the breakdown of potassium ( 40 P) to argon ( 40 Ar). http://www.aqd.nps.gov/grd/usgsnps/gtime/radiom.html

How do geologists date rocks? Radiometric dating! 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 . Since the 1950s, geologists have used radioactive elements as natural "clocks" for determining numerical ages of certain types of rocks. 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 ( P) 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

42. Radiometric Dating Stephen A. Nelson. radiometric dating. It provided a means by which the age of theEarth could be determined independently. Principles of radiometric dating. http://www.tulane.edu/~sanelson/geol212/radiometric_dating.htm

Geology 212 Petrology 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 25 my was accepted by most physicists, but considered too short by most geologists. Then, in 1905, 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. It provided a means by which the age of the Earth could be determined independently. 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.

43. Radiometric Dating RADIOMETRIC AND CHEMICAL DATING TECHNIQUES. A product is detectable (THE CLOCK);The rate of production of that product is know (THE TICKING CLOCK); http://www.geo.arizona.edu/palynology/geos462/10radiometric.html

RADIOMETRIC AND CHEMICAL DATING TECHNIQUES A product is detectable ( THE CLOCK The rate of production of that product is know ( THE TICKING CLOCK Product amount is (or known) at age of sample ( CLOCK SET TO ZERO Product / Rate = Time example: 10g / 0.5g/yr = 20 years Isotopes : elements with the same atomic number but different atomic mass. atomic number : number of protons in nucleus, e.g., 6-Carbon 7-Nitrogen, 19-Potassium atomic mass : number of protons + neutrons, e.g., Carbon 12, 13, 14; Potassium 39, 40 Written C to distinguish from ion charge C Some isotopes unstable K, C; while others are stable K, K, C, C Unstable isotopes decay to another stable or unstable Isotope Expressed as " half-life examples: C 5730 yr (5570, Libby) K 1.31 X 109 yr Pb 22 yr Radiocarbon half-lifes K/Ar dates are based on ratio of K / Ar trapped in sample, heating drives off argon gas, re-setting clock. Ar/ Ar relies on artificial production of Ar from K, which gives K / Ar ratio from same part of rock Pb DATING : radiometric dates for the last 100 year Origin of Pb : Uranium Decay Series Sources of Pb supported Pb produced by radioactive decay of sediments unsupported Pb transported to lake from watershed Models for Pb decay in sediment CRS - Constant rate of Supply CIC - Constant Initial Concentration RADIOCARBON DATING Carbon Isotope Ratios C/ C = 10 C/ C = 10 PRINCIPLES isotopes (and products) must be detectable n,p

44. The Unreliability Of Radiometric Dating Beta version this article is being revised and updated. The Unreliability of RadiometricDating By Jon Covey, BA, MT(ASCP) Edited by Anita Millen, MD, MPH, MA. http://www.creationinthecrossfire.com/documents/Radiomentric Dating/Radiometric

Beta version: this article is being revised and updated. The Unreliability of Radiometric Dating By Jon Covey, B.A., MT(ASCP) Edited by Anita Millen, M.D., M.P.H., M.A. Most people, including scientists, assume that radioactive dating methods, such as Carbon-14 or Uranium, are very reliable. Because of this, they view young earth creationists as foolish—akin to those who believe in a flat earth. Many think all one has to do to date a rock is put it into a machine, then the machine will count the radioactive decay incidents and convert it into a date we can understand. Few people are aware of the assumptions that must be made and the widely differing dates that can be obtained from samples of the same rock, vastly older or younger than the "accepted" age of the rock based on the fossil record of the geological layer from which it came. Philosophical predisposition, whether creationist or evolutionist, determines the assumptions made. Most people, including most scientists, are unaware of the pitfalls in the radiometric dating methods. The Young-Earth View Died with Lord Kelvin The Encyclopaedia Britannica (1997 CD-ROM) gave this account: Age of the Earth , Harold Slusher and Thomas Gamwell reexamined the time required for the earth cooling to its present temperature. They made five calculations for the cooling time based on a range of estimates, starting with presently known stores of radioactive materials in the earth. They concluded that even with unrealistically high estimates the earth could not have been cooling for more than one billion years. [Slusher]

45. Radiometric Dating radiometric dating. The discovery of radioactivity and its subsequentunderstanding provided a reliable means for calculating the http://academic.udayton.edu/SusanKlosterman/Stratigraphy/radiometric_dating.htm

46. Radiometric Dating Flaws Notes The validity of radiometric dating depends upon the three listedassumptions being correct. The decay rate being a constant http://emporium.turnpike.net/C/cs/basics/sld024.htm

Notes: Creationists have also advanced theories which may explain why rock samples appear to have old ages, and question the validity of the "isochron" dating procedure, which uses multiple samples. The bottom line is that radiometric dating procedures don't provide the consistent absolute dating method we would like to have. Go to Creation Science home page

47. Radiometric Dating Flaws radiometric dating Flaws. Answer Notes The validity of radiometric datingdepends upon the three listed assumptions being correct. The http://emporium.turnpike.net/C/cs/basics/tsld024.htm

Radiometric Dating Flaws Answer depends upon three assumptions: Decay rate has been a constant - probably true Start with no or known daughter component - unlikely Isolated system - no external loss/addition of parent or daughter components - very unlikely over millions of years Previous slide Next slide Back to the first slide View Graphic Version Notes: Creationists have also advanced theories which may explain why rock samples appear to have old ages, and question the validity of the "isochron" dating procedure, which uses multiple samples. The bottom line is that radiometric dating procedures don't provide the consistent absolute dating method we would like to have. Go to Creation Science home page

48. Radiometric Dating - Wikipedia radiometric dating. Probably the best known form of radiometric dating is radiocarbondating, which uses carbon14.Rubidum-Strontium dating is also popular. http://www.wikipedia.org/wiki/Radiometric_dating

Main Page Recent changes Edit this page Older versions Special pages Set my user preferences My watchlist Recently updated pages Upload image files Image list Registered users Site statistics Random article Orphaned articles Orphaned images Popular articles Most wanted articles Short articles Long articles Newly created articles All pages by title Blocked IP addresses Maintenance page External book sources Printable version Talk Log in Help Radiometric dating From Wikipedia, the free encyclopedia. Radiometric dating is the determination 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 are radioactive 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 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.

49. Radiometric Dating radiometric dating. radiometric dating A Christian Perspective. by Dr.Roger C. Wiens http//asa.calvin.edu/ASA/resources/Wiens.html. http://www.earth.rochester.edu/ees201/Emerson/Emerson.html

Radiometric Dating Ever since the harmful effects of radiation were discovered, radioactivity has been viewed as generally a bad thing by most people. It is seen very differently by geologists and other scientists. Radioactivity is the basis for radiometric dating. Ernest Rutherford in his Laboratory at McGill University ca. 1903, Rutherford is regarded as one of the founding fathers of the fields of nuclear physics and radioactivity. Introduction: History of Radioactivity radioactivity . The Curies discovered the phenomenon of spontaneous emission of rays during radioactive decay , and later discovered that a daughter element was formed from the decay of the parent element. The Curies' research and discoveries, led a British physicist Lord Ernest Rutherford (pictured above) to the discovery that the radiation of radioactive elements consisted of three kinds: alpha particles beta particles , and gamma rays . Through experimentation Rutherford discovered the half-life and the constancy of the decay rate , which established the basics for radiometric dating . Rutherford later defined the structure of the atom in his famous "Gold Foil Experiment".

50. Radiometric Dating And The Bible radiometric dating AND THE BIBLE A HISTORICAL REVIEW BTG No. 104a August 1997by Henry M . Morris*. © Copyright 2002 Institute for Creation Research. http://www.icr.org/pubs/btg-a/btg-104a.htm

Institute for Creation Research A Christ-Focused Creation Ministry "For in six days the Lord made the heaven and the earth, the sea, and all that in them is, and rested the seventh day..." Exodus 20:11 Main Menu Online Store About ICR Back to Genesis Days of Praise ... Tracts ICR Network Grad School ICR Adventures Jonathan Park RSAC Rated ... Donate RADIOMETRIC DATING AND THE BIBLE: A HISTORICAL REVIEW - BTG No. 104a August 1997 by Henry M . Morris "And God called the light Day, and the darkness He called Night. And the evening and the morning were the first day." (Genesis 1:5). The dating of rocks by the radioactive decay of certain minerals is undoubtedly the main argument today for the dogma of an old earth. But the Bible clearly teaches a recent creation of both the heavens and the earth, so Christians have often tried to reinterpret this doctrine to accommodate the long ages required by radioactive dating. For those Christians who believe that Genesis (like the other historical books of the Bible) should be understood as literal history, it has therefore been necessary to show the fallacies in the so-called "scientific proofs" of an old earth. During the century after Lyell and Darwin and up until about 1950, the reaction of practically all Christian leaders was to accept uniformitarianism and the radiometric ages, accommodating them by either the gap theory or the day-age theory.

51. Radiometric Dating radiometric dating USING ISOCHRONS IMPACT No. 113 Research. All RightsReserved. radiometric dating fascinates nearly everyone. http://www.icr.org/pubs/imp/imp-113.htm

Institute for Creation Research A Christ-Focused Creation Ministry "For in six days the Lord made the heaven and the earth, the sea, and all that in them is, and rested the seventh day..." Exodus 20:11 Main Menu Online Store About ICR Back to Genesis Days of Praise ... Tracts ICR Network Grad School ICR Adventures Jonathan Park RSAC Rated ... Donate RADIOMETRIC DATING USING ISOCHRONS - IMPACT No. 113 November 1982 by Dr. Russell Akridge Institute for Creation Research. All Rights Reserved. Radiometric dating fascinates nearly everyone. Uranium-lead, potassium-argon, and rubidium-strontium are names associated with radiometric dating. Jesus Christ talked about things that most of his listeners did not comprehend. He used parables. Hear now the parable of two scientists who analyze the fruit layer in the crust of the earth. THE HARVEST The man on the adjoining farm raises bananas and coconuts. Both of his crops yielded about the same. His truck was loaded with 50% bananas well-mixed with 50% coconuts.

52. How Good Are Those Young Earth Arguments Carbon-14 And The following material has been taken from a sheet entitled SeveralFaulty Assumptions Are Used in all radiometric dating Methods. http://www.infidels.org/library/modern/dave_matson/young-earth/carbon-14/

53. Radiometric Dating Of Fossils And Rocks radiometric dating of Fossils and Rocks The Failure and Inaccuracyof Radiodating and Radiocarbon Dating Methods. We are already http://www.cryingvoice.com/Evolution/Radiodating.html

Creation - Evolution Physics and Evolution Vestigial Organs Radiometric Dating of Fossils and Rocks The Failure and Inaccuracy of Radiodating and Radiocarbon Dating Methods We are already accustomed to such statements made in the media: scientists have discovered 65 million year old dinosaur bones in this or that location; scientists concluded that a certain rock is 4.5 billion years old. We don't even consider questioning the age of these findings. Scientists cannot be wrong so we say. We have heard about some of the dating methods, like radiocarbon dating, or uranium radiodating, but very few of us know much about how inaccurate these methods are, and yet they are presented as infallible scientific tools. In the following, we will take a closer look at these and other methods, and we will make an assessment of their accuracy. At the end we shall conclude that these dating methods are so unreliable that ultimately rocks and fossils cannot be dated by these, thus evolutionists must rely solely on theory. We have seen on the previous pages, that evolution cannot happen, regardless of how much time is available; one thousand or one billion years. Long time does not make possible the impossible. A tornado could rumble through a junkyard for billions of years, and still would not be able to assemble a Rolls Royce, let alone a whole Rolls Royce factory!

54. Exercise In Radiometric Dating (ans.) b. In order for radiometric dating to be accurate, how muchlead207 must we assume was present when the rock first formed? http://www.cat.cc.md.us/courses/eas101/unit1/radiometric2.html

Objectives Unit Labs Quiz Home Read This Material in Thompson and Turk (2nd Ed.): Section 4.6 Read These Notes: Below are some common parent /daughter pairs and their half-lives. Notice that the half-life varies from one radioactive material to another. Materials with a long half-life are useful in dating materials that are very ancient. They are most used to date the most ancient rocks and therefore are the ones used to date the Solar System. radioactive atoms such as Carbon-14 have short half-lives and therefore are used to date materials of more recent age. C-14 is commonly used in dating archeological sites, for example. Parent Daughter Half-life Use Carbon-14 Nitrogen-14 5,730 years Archeology Potassium-40 Argon-40 12,500 million years Geology Rubidium-87 Strontium-87 48,800 million years Archeology Uranium-235 Lead-207 704 million years Geology Uranium-238 Lead-206 4,470 million years Geology Thorium-238 Lead-208 14,010 million years Geology In order to calculate the age of a radioactive material, two things must be known: the abundance of either the parent or the daughter element.

55. RADIOMETRIC DATING This is referred to as radiometric dating. The validity of these assumptionsultimately determine the reliability of the radiometric dating method. http://www.cat.cc.md.us/courses/eas101/unit1/radiometric.html

Objectives Unit Labs Quiz Home Read This Material in Thompson and Turk (2nd Ed.): Section 4.6 Figure 1: Figure 2: Read These Notes: The solar nebula hypothesis provides a mechanism for solar system formation. How does one determine the date for its formation? Since we assume that the bodies that make up the solar system were formed at essentially the same time, we can determine the age of solar system by dating the bodies that make it up. One method that has been used is radiometric dating (def) Some elements are radioactive. Radioactive elements are the elements that are found at the bottom of the periodic table. The forces which normally hold the protons and neutrons together in the nucleus are insufficient, making these nuclei naturally unstable. Spontaneously the nuclei release nuclear particles in a process called radioactive decay (def) (figure 1). The result of radioactive decay is the release of both nuclear particles and energy. The original radioactive atom is called the parent (def) . The decay process changes the atomic number (def) of the parent, thereby its changing its elemental identity. The new element that is produced is called the daughter

56. Radiometric Dating Methods For example Carbon 14 is often the method of choice for scientists dating organicartifacts like wood, charcoal, bone, and teeth that are less than about http://www.clearlight.com/~mhieb/WVFossils/DatingMethods.html

HOW OLD IS IT? The absolute age of a wide variety of rocks, fossils, and human artifacts can be determined by various laboratory procedures. Deciding which test to perform depends on the composition and believed approximate age of a particular specimen. For example Carbon 14 is often the method of choice for scientists dating organic artifacts like wood, charcoal, bone, and teeth that are less than about 40,000 years. Carbon 14 as an isotope exists in Earth's atmosphere at more or less constant concentrations relative to other carbon isotopes (there are exceptions, which published tables compensate for). When living tissue dies the Carbon 14 begins to slowly decay. Carbon 14 has a half-life of about 5,370 years , meaning that every 5,370 years about 50% of it decays to it's daughter product , the Carbon 12 isotope. After another 5,370 years only 25% of it remains, and so on. After 40,000 years there isn't enough of it left to accurately measure, so to date anything much older requires use of one or more of the other age-determination methods. The Carbon 14 test would be inappropriate for something like, say, granite because what we already know about granite is that it is too old and of the wrong composition for that test. But the granite may very well contain traces of the elements Uranium, Rubidium, or Potassium, and a test using one or more of those isotope procedures may well be appropriate and yield good results.

57. Radiometric Dating radiometric dating. 12/2/02. Click here to start. Table of Contents.radiometric dating. Poor Lord Kelvin. . . Not only does the http://faculty.uca.edu/~benw/biol4415/lecture9a/

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. . . . ... Isochron Dating Author: Ben Waggoner Email: benw@mail.uca.edu Home Page: http://faculty.uca.edu/~benw/biol4415/

58. Radiometric Dating II radiometric dating II. 12/2/02. Click here to start. Table of Contents.radiometric dating II. Recall that, as melted rock cools http://faculty.uca.edu/~benw/biol4415/lecture9b/

Radiometric Dating II Click here to start Table of Contents Radiometric Dating II Recall that, as melted rock cools down, different compounds, i.e. different minerals, precipitate out of the meltóyou can see them in these transparent slices through common igneous rocks. As it cools, it fractionates into several minerals, each with a different value for [P], the concentration of the parent element . . . . And look what happens to the line over time. . . ... 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/biol4415/

59. Physical Geology Lecture - Radiometric Dating of NE. radiometric dating internal clocks in rocks. This assumption can be testedfor. Systems commonly used for radiometric dating, with half lives. http://maps.unomaha.edu/Maher/geo117/part2/117radiometric.html

Physical Geology (GEOL 1170) Lecture, H. D. Maher Jr., Univ. of NE Radiometric dating - internal clocks in rocks. Geochronology: the science of dating geologic materials. Basics of radioactive decay and isotopic dating. Radioactive decay occurs at an exponential rate, meaning that it can be described in terms of a half life. After one half live, half of the original radioactive isotope material in the system under consideration decays. Another half life and half of the remaining material decays, and so on. This is for unforced decay. Forced decay is when the isotopic material is packed densely enough that a decay in one unstable atom sends out a particle that hits another atom and causes it to decay. If it is packed too densely there is a run away reaction and one of those unpopular mushroom clouds or mneltdowns. Normal concentrations of radioactive material on earth are well below the levels where forced decay occurs so we can use the relatively simple mathematics of exponential decay to describe the process. the rate of decay is constant for earthly P-T conditions. A major assumption is that the rock or mineral being dated has been a closed system so that no parent isotope or daughter product has escaped or been added. This assumption can be tested for.

60. NewCreationism.Org - Radiometric Dating And How It Caused My Conversion To The O radiometric dating and How It Caused My Conversion To The Old Earth Perspective ByKevin Miller I had been a Christian for several years when I was confronted http://www.newcreationism.org/CreationArticle9.html

new Creationism.org Origins from the perspective of Intelligent Design and Old Earth Creationism powered by FreeFind Radiometric Dating and How It Caused My Conversion To The Old Earth Perspective By Kevin Miller If I was to be consistent with this view I needed to adjust my thinking on the age of the Earth and our Universe. I considered the idea that maybe the decay rates of nuclides had changed in the past or that maybe God made everything looking old but after considering all of the evidence that did not seem reasonable. Not to mention that when I looked at the results from dating methods from the field of astronomy all I found was consistency with the dates yielded from the methods of radiometric dating. References Don Stoner G. Brent Dalrymple Dr. Hugh Ross , Humphreys

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