LA-ICP-MS工作参数优化及在锆石U-Pb定年分析中的应用
发布时间：2018-07-25 09:22
【摘要】：将激光器(LA)和电感耦合等离子体质谱仪(ICP-MS)联用避免了溶液分析繁琐、耗时的前处理操作,减少了样品制备过程中可能带来的污染,同时又具备分析成本低、测试速度快、分析数据精度高等优势。本文将LA与ICP-MS联接使用,通过激光能量密度和剥蚀频率组合来讨论较低的元素分馏效应,同时匹配RF功率、采样深度、载气及He气流速等主要工作参数以获得较高的元素信号灵敏度和稳定性,从而得到仪器最优工作参数组合,建立了可靠的锆石U-Pb定年方法。通过对锆石标样91500、GJ-1及Ple2ovic互测结果表明,其206Pb/238U加权平均年龄分别为1063.9±6.0 Ma(2σ,n=20)、600.3±2.6 Ma(2σ,n=27)及337.6±1.7 Ma(2σ,n=20),测试结果准确度和精度均在1%范围内,与前人报道的误差范围一致。使用优化后的仪器参数对来自鄂东南铜绿山矿区石英正长闪长玢岩岩体中的实际锆石样品进行测试,获得其206Pb/238U年龄与前人研究结果基本一致,表明本法能准确地对锆石进行定年分析。
[Abstract]:The combination of laser (LA) and inductively coupled plasma mass spectrometer (ICP-MS) avoids the tedious solution analysis and time-consuming pretreatment operation, reduces the possible pollution in the sample preparation process, and at the same time has the advantages of low analysis cost and fast testing speed. Analysis of data accuracy and other advantages. In this paper, we use LA and ICP-MS to combine laser energy density and denudation frequency to discuss the low fractionation effect of elements, and match RF power and sampling depth. The main working parameters such as carrier gas and he gas flow velocity are used to obtain higher sensitivity and stability of element signal, thus the optimal working parameters combination is obtained, and a reliable zircon U-Pb dating method is established. The results of zircon standard 91500 GJ-1 and Ple2ovic show that the weighted mean age of 206Pb/238U is 1063.9 卤6.0Ma (2 蟽 / nnf20), 600.3 卤2.6Ma (2 蟽 / NJ ~ (27) and 337.6 卤1.7Ma (2 蟽 / n ~ (20) respectively. The accuracy and accuracy of the test results are in the range of 1%, which is in agreement with the error range reported by others. The actual zircon samples from quartz syenite porphyrite in Tonglushan mining area in southeastern Hubei Province were tested by using the optimized instrument parameters. The 206Pb/238U age of the zircon samples obtained is basically consistent with the results of previous studies. The results show that this method can accurately analyze zircon.
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本文编号：2143366
[Abstract]:The combination of laser (LA) and inductively coupled plasma mass spectrometer (ICP-MS) avoids the tedious solution analysis and time-consuming pretreatment operation, reduces the possible pollution in the sample preparation process, and at the same time has the advantages of low analysis cost and fast testing speed. Analysis of data accuracy and other advantages. In this paper, we use LA and ICP-MS to combine laser energy density and denudation frequency to discuss the low fractionation effect of elements, and match RF power and sampling depth. The main working parameters such as carrier gas and he gas flow velocity are used to obtain higher sensitivity and stability of element signal, thus the optimal working parameters combination is obtained, and a reliable zircon U-Pb dating method is established. The results of zircon standard 91500 GJ-1 and Ple2ovic show that the weighted mean age of 206Pb/238U is 1063.9 卤6.0Ma (2 蟽 / nnf20), 600.3 卤2.6Ma (2 蟽 / NJ ~ (27) and 337.6 卤1.7Ma (2 蟽 / n ~ (20) respectively. The accuracy and accuracy of the test results are in the range of 1%, which is in agreement with the error range reported by others. The actual zircon samples from quartz syenite porphyrite in Tonglushan mining area in southeastern Hubei Province were tested by using the optimized instrument parameters. The 206Pb/238U age of the zircon samples obtained is basically consistent with the results of previous studies. The results show that this method can accurately analyze zircon.
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本文编号：2143366
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