岩矿测试2025，Vol.44Issue(3)：369-383,15.DOI:10.15898/j.ykcs.202403160057
低铀方解石高空间分辨率LA-MC-ICP-MS U-Pb测年方法
High Spatial Resolution U-Pb Dating of Low-Uranium Calcite Using LA-MC-ICP-MS
摘要
Abstract
The combination of carbonate minerals with the U-Pb isotope dating system provides direct temporal constraints for geoscientific applications.LA-MC-ICP-MS with its high sensitivity and accuracy,has been successfully applied to the high spatial resolution U-Pb dating of zircon,calcite and other minerals.The experimental parameters of LA-MC-ICP-MS were optimized in detail,and a high spatial resolution U-Pb dating method was established for low-uranium calcite minerals.The effects of cone combination,GE mode,N2 introduction and Ar carrier gas flow rate on the U and Pb signal intensity and oxide yield(UO/U)were discussed in detail.The results showed that the highest sensitivity of Pb was achieved under the conditions of Jet+X cone combination,guard electrode(GE)grounded state,8mL/min N2 introduction and 0.9L/min Ar carrier gas flow rate,while the oxide yield(UO/U)was lower than 1％.Three low uranium(0.04-0.63μg/g),calcite U-Pb dating reference materials were used to validate the reliability of the method.Samples LD-5,PTKD-2 and TARIM yielded a lower intercept age of 73.20±0.56Ma,152.7±2.5Ma and 206.2±1.3Ma,respectively,under the condition of 44μm beam spot,which were in agreement with the calibrated results of ID-TIMS/ID-MC-ICP-MS within the error range.The BRIEF REPORT is available for this paper at http://www.ykcs.ac.cn/en/article/doi/10.15898/j.ykcs.202403160057.关键词
低铀方解石/U-Pb测年/LA-MC-ICP-MS/高空间分辨率/参数优化Key words
low-uranium calcite/U-Pb dating/LA-MC-ICP-MS/high spatial resolution/parameter optimization分类
地质学引用本文复制引用
张晨西,熊玉新,付佳丽,赵伟,舒磊,李增胜,徐珺,周长祥,洪飞..低铀方解石高空间分辨率LA-MC-ICP-MS U-Pb测年方法[J].岩矿测试,2025,44(3):369-383,15.基金项目
山东省自然科学基金项目(ZR2022QD050) （ZR2022QD050）
自然资源部金矿成矿过程与资源利用重点实验室和山东省金属矿产成矿地质过程与资源利用重点实验室开放课题(Kfkt202118) （Kfkt202118）
江西省自然科学基金项目(20232BAB213070) （20232BAB213070）
国家自然科学基金项目(42203034) （42203034）
