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| - Radiometric dating is a technique used to date materials based on a knowledge of the decay rates of naturally occurring isotopes, and the current abundances. It is our principal source of information about the age of the Earth and a significant source of information about rates of evolutionary change. Various methods exist differing in accuracy, cost and applicable time scale.
- Radiometric dating is finding the dates of objects using the radioactive decay of some of their materials. One compares the amounts of parent and descendant isotopes, using other isotopes of their elements as a reference. There are several isotope sets that have been used for radiometric dating, like uranium-lead, potassium-argon, samarium-neodymium, rubidium-strontium, and radiocarbon. Young-earth creationists have a variety of objections to radiometric dating, all of which are successfully answered.
- 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. Together with stratigraphic principles, radiometric dating methods are used in geochronology to establish the geological time scale. 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 informat
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| abstract
| - Radiometric dating is finding the dates of objects using the radioactive decay of some of their materials. One compares the amounts of parent and descendant isotopes, using other isotopes of their elements as a reference. There are several isotope sets that have been used for radiometric dating, like uranium-lead, potassium-argon, samarium-neodymium, rubidium-strontium, and radiocarbon. Young-earth creationists have a variety of objections to radiometric dating, all of which are successfully answered.
* It requires assumptions about initial composition. One can get around that problem in several ways.
* Known initial composition. Zircon is useful for uranium-lead dating because its crystal structure can incorporate uranium but not lead. So one can be confident that all a zircon's lead was produced by radioactive decay.
* Use of variations in initial composition. Different minerals have different affinities for the parent and descendant elements, and one can sort them out by grinding up the rock and dating each grain separately.
* Outside calibration. Radiocarbon dating is calibrated by dating wood from long-ago trees, wood that is dated using its annual growth rings. It has been possible to go back about 10,000 years, though doing so has required correlating the rings of a large number of trees over that time.
* It requires assuming that decay rates are constant. Here also, there are ways of getting around it.
* Most radioactive decay is not measurably altered by environmental conditions, as is evident from both theory and experiment. One needs extreme conditions, like inside the core of a massive star, to make much of a difference in most cases.
* Continental-drift rates estimated with radiometric dating agree with present-day drift rates found with quasars and GPS satellites and the like.
* Milankovitch astronomical cycles have the "right" periods over the parts of geological time where they have been compared to radiometric dates.
* Different radioisotopes would give different dates, and there is no evidence of such systematic discrepancies.
* Carbon-14 has been found in coal. However, it is a case of secondary radioactivity; radioactivity induced by other radioactivity.
- Radiometric dating is a technique used to date materials based on a knowledge of the decay rates of naturally occurring isotopes, and the current abundances. It is our principal source of information about the age of the Earth and a significant source of information about rates of evolutionary change. Various methods exist differing in accuracy, cost and applicable time scale.
- 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. Together with stratigraphic principles, radiometric dating methods are used in geochronology to establish the geological time scale. 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. Image:Mantell's Iguanodon restoration.jpg This article is a . You can help My English Wiki by expanding it.
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