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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.
Uranium–lead dating is often performed on the mineral zircon (ZrSiO 4), though it can be used on other materials, such as baddeleyite and monazite (see: monazite geochronology). [23] Zircon and baddeleyite incorporate uranium atoms into their crystalline structure as substitutes for zirconium, but strongly reject lead. Zircon has a very high ...
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samples, normally based on 'whole-rock' samples of material such as granite.For most dating requirements it has been superseded by uranium–lead dating (U–Pb dating), but in certain specialized situations (such as dating meteorites and the age of the Earth) it is more important than U–Pb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.
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 ...
Uranium–lead dating Uranium–thorium dating Uranium–uranium dating , useful in dating samples between about 10,000 and 2 million years Before Present (BP), or up to about eight times the half-life of 234U.
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 ...
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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 ...