Geometry.Net - Science: Radiometric Dating

Amazing Discoveries:: Radiometric Dating - Page 1
radiometric dating page 1. A radioactive element is capable of changinginto a new element by the emission of a charged particle.
http://www.amazingdiscoveries.org/rad_dating.html

Extractions: Radiometric Dating [page 1] In other words, all methods of radioactive dating rely on some a priori assumptions which may not necessarily be true. These are: The rate of radioactive decay and half-lives has remained constant over time. This assumption has the backing of numerous scientific studies and is relatively sound, however, conditions may have been different in the past and could have influenced the rate of decay or formation of radioactive elements.
Amazing Discoveries:: Radiometric Dating - Page 2
radiometric dating page 2. Zero Reset. Many examples from literatureshow that the zero reset assumption is not always valid.
http://www.amazingdiscoveries.org/rad_dating-p2.html

Extractions: Radiometric Dating - [page 2] Zero Reset Many examples from literature show that the zero reset assumption is not always valid. Volcanic ejecta of Mount Rangitoto (Auckland, New Zealand) was found to have a potassium-40 age of 485,000 years, yet trees buried within the volcanic material were dated with the carbon-14 method to be less than 300 years old. (. McDougall, A.A. Polach and J.J. Stipp, "Excess Radiogenic Argon in Young Subaerial Basalts From Auckland Volcanic Field, New Zealand," Geochemica et Cosmochemica Acta 33:1485-1520, 1969.) A further example from a lava flow off the coast of Hawaii shows similar discrepancies. If dated with the carbon-14 method, the flow appears to be less than 10 000 to 17 000 years old, but dating with the potassium argon method gives dates of 160 000 to 43 million years. A rock sample from Nigeria was dated at 95 million years by the potassium-argon method, 750 million years by the uranium-helium method, and less than 30 million years by the fission-track method. (.E. Fisher, "Excess Rare Gases in a Subaerial Basalt from Nigeria," Nature 232, 1971: 60,61.) There are numerous examples in the literature which cast doubt on the clock reset hypothesis. If the clock is not set to zero when a deposit forms, then there can be no starting point from which to calculate the age of a deposit.
Unreliability Of Radiometric Dating And Old Age Of The Earth
radiometric dating. Photo Gallery of Dating errors. Scientific Essay by DavidA. Plaisted. radiometric dating. Scientific Essay by David A. Plaisted.
http://www.bible.ca/tracks/dating-radiometric.htm

Extractions: Radiometric Dating Photo Gallery of Dating errors Scientific Essay by David A. Plaisted "Proof of the pudding" There are circumstances that provide opportunities for testing. Dinosaurs which are supposed have lived at least 60 million years ago, should not yield dates of thousands of years. Rocks known to have formed in historical times should not yield dates of millions of years. Dinosaur Bone The new lava dome (dacite) from the at Mount St. Helens was formed in 1986. In 1997 five specimens were taken from this dome at five different locations and subjected to conventional Potassium-Argon dating. The results indicated ages of less than one half to almost three million years old, all from eleven year old rock.
Evolution: Library: Radiometric Dating
radiometric dating. Topics Covered Deep Time/History of Life. Backgrounder. RadiometricDating Geologists have calculated the age of Earth at 4.6 billion years.
http://www.pbs.org/wgbh/evolution/library/03/3/l_033_01.html

Extractions: 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. Hutton's theories were short on evidence at first, but by 1830 most scientists concurred that Noah's ark was more allegory than reality as they documented geological layering. Using fossils as guides, they began to piece together a crude history of Earth, but it was an imperfect history. After all, the ever-changing Earth rarely left a complete geological record. The age of the planet, though, was important to
A Science Odyssey: People And Discoveries: Radiometric Dating Finds Earth Is 2.2
radiometric dating finds Earth is 2.2 billion years old 1907 In 1902Ernest Rutherford and Frederick Soddy discovered that radioactive
http://www.pbs.org/wgbh/aso/databank/entries/do07ra.html

Extractions: In 1902 Ernest Rutherford and Frederick Soddy discovered that radioactive elements, such as uranium and thorium, broke down into other elements in a predictable sequence or series. This amazing fact seemed like alchemy to many, but American chemist Bertram Borden Boltwood (1870-1927) was intrigued. Boltwood studied this concept of "radioactive series," and found that lead was always present in uranium and thorium ores. He believed that lead must be the final product of the radioactive decay of uranium and thorium. A few years later, in 1907, he reasoned that since he knew the rate at which uranium breaks down (its half-life), he could use the proportion of lead in the uranium ores as a kind of meter or clock. The clock would tell him how long that ore and by extension, the earth's crust had existed. His observations and calculations put Earth's age at 2.2 billion years. This was a dramatic increase in the estimate of Earth's age for the time. Boltwood's basic idea and technique have been used ever since 1907, but advances in technology and knowledge of atomic structure have shown the earth to be even older. Uranium decay is so slow it can indicate geologic time. Boltwood's reasoning holds true for other radioactive elements such as
Radiometric Dating
radiometric dating. radiometric dating. During the 19th century, and evenwell into the twentieth, geological chronology was very crude.
http://www.palaeos.com/Geochronology/radiometric_dating.htm

Extractions: Links Different world-views have different time-scales as regards the history of the Earth and the universe. Buddhist , Jain and Hindu cosmologies describe the universe as a never-ending series of cycles each lasting millions or billions of years. The Greeks had the "great year" of 24,500 years, based on the precession of the equinoxes. The time-scale of the fundamentalist or Creationist Judeo-Christian is based on a word-for-word reading of the first book of the Bible, and assumes a total age of the earth and the cosmos of a mere 5 or 6,000 (some Creationists allow 10,000) years. Astronomy and Geology, working on scientific data built up over the last two centuries or so, assumes the Earth to be very ancient, more in keeping with the eastern than the western (Graeco-Judeo-Christian) perspectives. However, whereas the
Radiometric Dating
radiometric dating by Frank Steiger Copyright © 1996 radiometric datingis a means of determining the age of a mineral specimen
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:
NCSE Resource
radiometric dating of rocks and minerals using naturally occurring, longlivedradioactive isotopes is troublesome for young-earth creationists because the
http://www.ncseweb.org/resources/rncse_content/vol20/8906_radiometeric_dating_do

Extractions: The creationist approach of focusing on examples where radiometric dating yields incorrect results is a curious one for two reasons. First, it provides no evidence whatsoever to support their claim that the earth is very young. If the earth were only 600010 000 years old, then surely there should be some scientific evidence to confirm that hypothesis; yet the creationists have produced not a shred of it so far. Where are the data and age calculations that result in a consistent set of ages for all rocks on earth, as well as those from the moon and the meteorites, no greater than 10 000 years? Glaringly absent, it seems. Second, it is an approach doomed to failure at the outset. Creationists seem to think that a few examples of incorrect radiometric ages invalidate all of the results of radiometric dating, but such a conclusion is illogical. Even things that work well do not work well all of the time and under all circumstances. Try, for example, wearing a watch that is not waterproof while swimming. It will probably fail, but what would a reasonable person conclude from that? That watches do not work? Hardly. A few verified examples of incorrect radiometric ages are simply insufficient to prove that radiometric dating is invalid. All they indicate is that the methods are not infallible. Those of us who have developed and used dating techniques to solve scientific problems are well aware that the systems are not perfect; we ourselves have provided numerous examples of instances in which the techniques fail. We often test them under controlled conditions to learn when and why they fail so we will not use them incorrectly. We have even discredited entire techniques. For example, after extensive testing over many years, it was concluded that uranium-helium dating is highly unreliable because the small helium atom diffuses easily out of minerals over geologic time. As a result, this method is not used except in rare and highly specialized applications. Other dating techniques, like K-Ar (potassium-argon and its more recent variant
One Of The Main Objections To Radiometric Dating
One of the main objections to radiometric dating (on the part of young earth creationists)is that radiometric ages do not agree with each other or that
http://gondwanaresearch.com/radiomet.htm

Extractions: Updated April 30, 2002 (links fixed, added) O ne of the main objections to radiometric dating (on the part of young earth creationists) is that radiometric ages do not agree with each other or that contamination renders ages meaningless. In fact, the claim is partially true. Early mass spectrometers were not as sensitive as machines today and the methods for separating, cleaning and analysis were less sophisticated. Although ye-creationists like Snelling talk about contamination of isotopic systems as if it were a foreign concept to modern geology, most geochronologists a Rock/Location Method Age +/- Error Reference 1. Fen Complex, Norway-A Ar/ Ar 588 +/- 10 Ma Meert et al, 1998 2. Fen Complex, Norway-B Ar/ Ar 578 +/- 10 Ma Meert et al., 1998 3. Fen complex, Norway K-Ar whole rock 575 +/- 25 Ma (average) Verschure et al., 1983 4. Fen Complex, Norway Rb-Sr isochron (phlogopite) 578 +/- 24 Ma Dahlgren, 1994
Radiometric Dating Methods Q&A
How accurate is Carbon14 dating? (Chapter from the Answers Book. Deals notonly with 14 C dating but also with other forms of radiometric dating);
http://aig.gospelcom.net/home/area/faq/dating.asp

Extractions: Defending the Christian faith beginning with Genesis AiG Worldwide Creation Education Prayer Good News ... About Us Psalm 138:2b Thou hast magnified thy word above all thy name Alien/UFOs Apologetics Archaeology Arguments NOT to use Bible Cloning Countering the Critics Creation Compromises Creation: Why It Matters Darwin, Charles 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 Mammoths Morality and Ethics Mutations Natural Selection Origin of Life Philosophy Plate Tectonics Probabilities Racism Radiometric Dating Religion (humanism, etc.) Speciation Thermodynamics and Order Young Age Evidence Recommended Resources Answers Book (Semi-technical) Fingerprints of Creation (video) God at Ground Zero In the Minds of Men Does Carbon Dating Disprove the Bible? (booklet) ... Mythology of Modern Dating Methods (Technical) Radioisotopes and the Age of the Earth (Technical) The Young Earth Radiocarbon, Creation, and the Flood (video)
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 K) to argon ( 40 Ar).
http://wrgis.wr.usgs.gov/docs/parks/gtime/radiom.html

Extractions: 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.
Radiometric Dating
radiometric dating. Pamela JW Gore Georgia Perimeter College. How do we determinethe age of a rock? radiometric dating. Principles of radiometric dating.
http://www.gpc.peachnet.edu/~pgore/geology/historical_lecture/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 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: Uranium 238
Radiometric Dating
radiometric dating. Sometimes they use a process called radiometric dating,in which they measure the amount of a radioactive element in a object.
http://www.island.net/~superior/evolution/radio.html

Extractions: Evolutionists claim the Earth is billions of years old. How do they reach this conclusion? Sometimes they use a process called radiometric dating, in which they measure the amount of a radioactive element in a object. They know that some elements change into other elements at a constant rate. By measuring the amount of the reactants and products in a dead plant or animal, they believe they can estimate the age of an object. However, this scientific process is flawed. Scientists assume that none of the reactant or product elements in the sample were removed by outside processes other than the normal change. They also assume that no reactant or product element was added by outside processes. For example, if a half-filled bowl of water is left in the sunshine, the water will evaporate. However, if the bowl was left alone while the water was evaporating and only checked every five minutes, how could one be sure that water was neither taken from or added to the bowl?
Age Of The Earth
radiometric dating from The Evolution Evidence Page Scientists have Creation Science Arguments Against radiometric dating. Now, what
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.
Hiding The Numbers To Defame Radiometric Dating
home1.gif (2214 bytes). Hiding the Numbers to Defame radiometric dating A Few Examplesof the Many Misused References in Woodmorappe (1999). Dr. Kevin R. Henke.
http://home.austarnet.com.au/stear/hiding_the_numbers_woody_henke.htm

Extractions: Woodmorappe (1999) Dr. Kevin R. Henke The following material may be freely copied and distributed as long as it's not altered, edited or sold. Woodmorappe (1999) presents numerous examples of what he claims are "discrepant" radiometric dates that contradict each other, fossil data, field structures and/or stratigraphic evidence. For example, Woodmorappe (1999, p. 41) quotes the following statement from Swisher et al. (1993, p. 1994) to "demonstrate" that dates from Evernden et al. (1964), which were once highly regarded and characterized as state-of-the-art, are now considered unreliable: Yet, how anomalously old are Evernden et al.'s results? We find the answer in the proceeding sentences, which Woodmorappe (1999, p. 41) chooses to ignore. Here's a more complete quotation from Swisher et al. (1993, p. 1993-1994): Swisher et al. (1993, p. 1993-1994) are arguing over trivial errors of about 1% and Woodmorappe (1999, p. 41, 52) is misleading us into believing that these errors are huge and fatal to radiometric dating! In another example, Woodmorappe (1999, p. 40-41) quotes Prothero (1994, p. 60) and argues that K-Ar dates from Evernden et al. (1964), which had been used to calibrate the Eocene-Oligocene boundary of the geologic time scale, were later shown to be "unreliable":
A Radiometric Dating Resource List
home1.gif (8619 bytes) radiometric dating the Truth! A radiometric dating ResourceList (off site). radiometric dating a Christian Perspective (off site).
http://home.austarnet.com.au/stear/a_radiometric_dating_resource_list.htm

Extractions: Radiometric Dating - the Truth! Radiometric dating is the process of determining the age of rocks from the decay of their radioactive elements. Creationists rely for their young Earth theories on falsifying the radiometric dating processes. In the links below you will find abundant evidence for the veracity of radiometric dating. Dr Kevin R. Henke exposes the poor science
Evolution Happens Radiometric Dating Page
APPENDIX Common Misconceptions Regarding radiometric dating Methods From RadiometricDating A Christian Perspective, 2nd Edition, by Dr. Roger C. Wiens.
http://www.evolutionhappens.net/radiometric.htm

Extractions: 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.
Radiometric Dating
radiometric dating, What is It? You've heard us mention radiometricdating. Have you wondered what it is? As in history, where the
http://www.mnh.si.edu/anthro/humanorigins/whatshot/1998/radio.html

Extractions: You've heard us mention radiometric dating. Have you wondered what it is? As in history, where the temporal context of an event is just as important as the event itself, the chronological position of an early human fossil is critical to the understanding of the species. Without proper understanding of the time period represented by an early human species, no evolutionary relationship can be interpreted. Since evolution is change over time, and time is a variable that must be controlled. One of the tools at the disposal of researchers is the radiometric dating technique. There are many such techniques, but each relies on the principle borrowed from physics that radioactive elements will decay at a constant rate. So an object can be dated using the clock created by the continual "click" of the radioactive atoms. Another technique of particular use to paleoanthropologists is the K/ AR (Potassium-40/Argon-40) technique. This technique is specific to volcanic materials, dating the breakdown of the radioactive Potassium-40 isotope into the stable and inert gas Argon-40.
Radiometric Dating
radiometric dating Its Faults! Dating Dinosaurs Interest in dinosaurscan be traced back to 1810 when Mary Anning discovered the
http://www.case-creation.org.uk/dating1.html

Extractions: Interest in dinosaurs can be traced back to 1810 when Mary Anning discovered the first complete skeleton of an Icthyosaurus in the cliffs at Lyme Regis, England. In 1824, in the same Dorset cliffs, she found the fossilized remains of a Plesiosauros and four years later she uncovered the first English Pteradactyl.
Radiometric Dating
radiometric dating Its Faults! The carbon Candle in the Wind. Theprinciple behind radiometric dating is fairly simple. We can
http://www.case-creation.org.uk/dating2.html

Extractions: The carbon 14 method for assessing the age of an object is based upon the measurement of the ratio of carbon 14 to carbon 12 found in all living tissues. Every living organism, whether plant or animal, collects carbon 12 and the radioactive carbon 14. When an organism dies, the carbon 14 and carbon 12 accumulation stops but the radioactive carbon 14 decays to nitrogen. The ratio of carbon 14 to carbon 12 in a sample can be measured, giving an indication of the date of death. "The principle behind radiometric dating is fairly simple. We can illustrate it by reference to a candle which is found burning in a room. From the present and original sizes of the candle and the rate at which it is burning, we can calculate how long it has been alight. For example, consider the case when it is 4 cm long and was originally 10 cm in length If it is burning at the rate of 1 cm an hour, then the 6 cm that have disappeared would have taken (6 cm) / (1 cm/hour) = 6 hours. But there are several possible sources of doubt or error here. How do we know that it was 10 cm long originally? How do we know that it was always burning at the same rate? (A draught could cause it to burn faster!) If we do not know the original length, we could (theoretically) collect all the soot and fumes formed and weigh them. That would enable us to determine the weight lost (and so the length) of the candle. But we would have to be sure none escaped and there was no soot in the room already!

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