U pb dating of zircon

Because zircons can survive geologic processes like erosion, transport, even high-grade metamorphism, they contain a rich and varied record of geological processes.

Currently, zircons are typically dated by uranium-lead (U-Pb), fission-track, cathodoluminescence, and U Th/He techniques.

The U–Pb ages revealed that the Toya Tephra contains zircons with ages that cluster at ~ 0.1 Ma (0.11 ± 0.01 Ma: error shown as 95% confidence level) and xenocrysts with ages 2 Ma, the U–Th method also gave an isochron age of ~ 0.1 Ma (108 ± 19 ka or 0.11 ± 0.02 Ma; error shown as 2σ).

Therefore, both U–Pb and U–Th methods result in similar ages of ~ 0.1 Ma for the Toya Tephra, in agreement with the quartz TL age (104 ± 30 to 118 ± 30 ka) of Ganzawa and Ike (2011).

In addition, the oxygen isotopic compositions of some of these zircons have been interpreted to indicate that more than 4.4 billion years ago there was already water on the surface of the Earth.

In the Variscan belt of Western Europe, the lifetime and evolution of the oceanic domain is poorly constrained by sparse, outdated and unreliable multigrain ID-TIMS U-Pb zircon dating.

The name derives from the Persian zargun meaning gold-hued. It occurs as a common accessory mineral in igneous rocks (as primary crystallization products), in metamorphic rocks and as detrital grains in sedimentary rocks.

Zircon is also very resistant to heat and corrosion.It was also revealed that the Toya Tephra magma crystallized zircons and experienced eruptions instantaneously at ~ 0.1 Ma, which is an important implication to decipher magmatic and eruptive processes for caldera-forming large volcanic systems. Zircon forms in silicate melts with large proportions of high field strength incompatible elements.The combination of U-Th disequilibrium/U-Pb and (U-Th)/He dating of zircon (ZDD) has provided a relatively new radiometric approach suitable for dating Quaternary zircon-bearing volcanic and pyroclastic deposits.This approach permits the dating of zircon as young as ca.For example, hafnium is almost always present in quantities ranging from 1 to 4%.

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