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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. [2] [3] The method is usually applied to zircon.
One of its great advantages is that any sample provides two clocks, one based on uranium-235's decay to lead-207 with a half-life of about 700 million years, and one based on uranium-238's decay to lead-206 with a half-life of about 4.5 billion years, providing a built-in crosscheck that allows accurate determination of the age of the sample ...
Zircon is a strong tool for uranium-lead age determination because of its inherent properties: [8] Zircon contains high amount of uranium for machine recognition, commonly 100–1000 ppm. [8] Zircon has a low amount of lead during crystallization, in parts per trillion. [8] Thus, lead found in zircon can be assumed as daughter nuclei from ...
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samples, normally based on 'whole-rock' samples of material such as granite.For most dating requirements it has been superseded by uranium–lead dating (U–Pb dating), but in certain specialized situations (such as dating meteorites and the age of the Earth) it is more important than U–Pb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.
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However, uranium–lead dating on zircon [4] and Argon-argon dating on sanidine and hornblende are the two single methods that achieve today the best results. [ 5 ] Other methods of radiometric dating are also available, that are based on slightly or largely different principles, but always rely on the phenomenon of radioactive decay .
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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.