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Uranium–lead dating, abbreviated U–Pb dating, is one of the oldest [1] and most refined of the radiometric dating schemes. It can be used to date rocks that formed and crystallised from about 1 million years to over 4.5 billion years ago with routine precisions in the 0.1–1 percent range.
Together with stratigraphic principles, radiometric dating methods are used in geochronology to establish the geologic time scale. [3] Among the best-known techniques are radiocarbon dating, potassium–argon dating and uranium–lead dating.
Lead–lead dating is a method for dating geological samples, normally based on 'whole-rock' samples of material such as granite.For most dating requirements it has been superseded by uranium–lead dating (U–Pb dating), but in certain specialized situations (such as dating meteorites and the age of the Earth) it is more important than U–Pb dating.
Monazite geochronology is another example of U–Pb dating, employed for dating metamorphism in particular. Uranium–lead dating is applied to samples older than about 1 million years. Uranium–thorium dating. This technique is used to date speleothems, corals, carbonates, and fossil bones. Its range is from a few years to about 700,000 years.
Zircon is extremely useful for geological dating: when forming, it collects tiny imperfections of uranium, but never lead. It follows that if lead is present in zircon, it must have come from decay of the uranium present. (The process is known as U-Pb dating.) The team measured the concentrations and isotopic compositions of foreign elements ...
The following year, Boltwood made the assertion that lead was the final decay product in the disintegration of uranium, and that Pb:U ratios increase in older geological samples. In 1907, he published results of analyzing ten mineral samples from different world locations, including a thorianite [ 2 ] that measured 2.2 billion years old.
The most common dating method is uranium-lead dating, which is used to date rocks older than 1 million years old and has provided ages for the oldest rocks on Earth at 4.4 billion years old. [14] The relation between 238 U and 234 U gives an indication of the age of sediments and seawater that are between 100,000 years and 1,200,000 years in ...
Arthur Holmes FRS FRSE (14 January 1890 – 20 September 1965) was an English geologist who made two major contributions to the understanding of geology. He pioneered the use of radiometric dating of minerals, and was the first earth scientist to grasp the mechanical and thermal implications of mantle convection, which led eventually to the acceptance of plate tectonics.