christian dating online totally - U pb dating of zircon by la icp ms
These characteristics, and the fact that it is widespread throughout various types of rocks, suggest that the U-Th-Pb dating of xenotime has broad applications.
Studies of U-Pb dating on xenotime by ion microprobe (such as SHRIMP) have increased in recent years, whereas studies by laser ablation (LA)-ICP-MS are still rare.
Inclusions in zircons, as well as signal fluctuations are eliminated by removing outliers from the regression line.
Non-stoichoimetric fractionation, mass bias, machine drift, and other variation are corrected by the external standards.
A blank is measured before every analysis, and a standard is measured every 5-6 analyses.
Laser induced time-dependant elemental fractionation is corrected off-line using the regression line method (Sylvester and Ghaderi, 1997; Horn et al., 2000; Kosler et al., 2002).
The samples are magmatic rocks chosen from different geological time periods (one Paleozoic, one Mesozoic and three Cenozoic).
All zircon separates are analysed by LA-ICP-MS before and after CA, and age data are compared with CA-ID-TIMS U dates that are considered as the most accurately obtainable age.
The use of the CA technique for very young zircons (∼0.2 Ma, Kos rhyolitic tuff, Greece) seems optional; as the obtained mean U ages of non-CA and CA treated zircons coincide within the uncertainty.
Xenotime is an ideal mineral for U-Th-Pb isotopic dating because of its relatively high U and Th contents, but typically low concentration of common Pb.
The damaged crystal parts, caused by U-decay, with lead loss are removed, so that we can exclude younging from the possible geological scenarios.Tags: Adult Dating, affair dating, sex dating