| Autor: |
Zhi Chen, Li-Guang Wu, Xiao-Xiao Ling, Wotzlaw, Jörn-Frederik, Chelle-Michou, Cyril, Yang Li, Zhen-Hui Hou, Wen-Lei Song, Qian Mao, Wen-Qiang Yang, Yu Liu, Guo-Qiang Tang, Jiao Li, Qiu-Li Li, Xian-Hua Li |
| Předmět: |
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| Zdroj: |
JAAS (Journal of Analytical Atomic Spectrometry); Oct2024, Vol. 39 Issue 10, p2580-2590, 11p |
| Abstrakt: |
In situ U-Th-Pb geochronology of monazite is widely used to reveal geological histories. Well characterized matrix-matched reference materials are crucial for achieving accurate results in microbeam U-Th-Pb dating. In this paper, the internal structure, chemical composition and U-Th-Pb dates of M6 monazite are investigated using multiple analytical methods to evaluate its potential as a reference material for in situ monazite U-Th-Pb dating. The results show that M6 monazite has an average ThO2 content of 10.7 ± 1.1% (2SD; SD = standard deviation) and Th/U ratio of 28.4 ± 3.3 (2SD). In situ U-Th-Pb dates from laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and secondary ion mass spectrometry (SIMS) laboratories are reproducible and homogeneous at the spatial level of 30 μm. Seven 207Pb/235U dates from isotope dilution-thermal ionisation mass spectrometry (ID-TIMS) yield a mean date of 485.7 ± 2.3 Ma (2SD), which is our recommended date for M6 monazite. Furthermore, SIMS oxygen isotope determinations show good measurement reproducibility (7.70& ± 0.41&, 2SD) and the LA-MC-ICP-MS analyses yield homogeneous Sm-Nd isotopic composition (143Nd/144Nd = 0.511829 ± 0.000045, 2SD; 147Sm/144Nd = 0.2302 ± 0.0139, 2SD), demonstrating that M6 monazite has the potential to be a reference material for in situ O and Sm-Nd isotopic analyses. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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