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对于不同类型的地球化学勘查样品 ,运用恰当的分析方法处理 ,是成功地发现矿床的关键。激光熔融电感耦合等离子质谱分析 ,即LA ICPMS ,是功能最强的多元素分析技术之一。该方法获得数据快捷 ,样品制备简单 ,其高灵敏度为很多主元素和微量元素 (包括铂族元素、稀土元素、高场强元素和多种成矿示踪元素 )提供了低检测限 ,正在并将要持续为地球化学应用提供新的信息。仪器由ICPMS(四极 ,多接受或磁扇域 )附加激光器 (紫外或红外波长 )而构成。应用于地球科学研究的标准仪器的激光器为具有 2 6 6nm四倍频率的Nd :YAG激光器 ,或者是具有 193nm波长的ArF激态原子激光器。激光器熔融样品 ,并通过运载气体将熔融的样品物质传送到IP ,而不是将样品溶解后 ,通过雾化器和雾化室将样品传输给ICP。这就使我们能够进行微区分析 ,如矿物环带 ,或者矿物中的微小矿物、融体和流体包裹体等。运用外标校对元素比值 ,并结合内标使用 ,可以获得定量测试结果。对于固体熔融物的分析精度一般为 2 %～ 5 %RSD(相对标准误差 ) ,对于流体包裹体则为 10 %～ 30 %RSD。LA ICPMS的一些复杂系统可能引起成分分馏和质量干扰。对于分馏效应 ,可以通过运用产生小粒子的短波长激光器和运用He作为运载气体来减小 ;对于质量干扰 ,则可以通过?
For different types of geochemical exploration samples, the use of appropriate analytical methods is the key to successful deposit discovery. Laser melting inductively coupled plasma mass spectrometry, LA ICPMS, is one of the most powerful multi-element analytical techniques. The method is fast in data acquisition and simple in sample preparation. Its high sensitivity provides low detection limits for many major and trace elements including platinum group elements, rare earth elements, high field strength elements and various metallogenic tracer elements. It will continue to provide new information for geochemical applications. The instrument consists of an additional laser (UV or IR wavelength) from ICPMS (quadrupole, multi-acceptance or magnetic sector). Lasers for standard instruments used in earth science research are Nd: YAG lasers with a quadruple frequency of 26 6 nm, or ArF excimer lasers with a wavelength of 193 nm. Instead of dissolving the sample, the laser transmits the sample to the IP through the nebulizer and the atomization chamber, using the carrier gas to deliver the molten sample mass to the IP. This allows us to perform microanalysis such as mineral annuli, or tiny minerals in minerals, melts and fluid inclusions. The use of external standard proofreading element ratio, combined with the use of internal standard, you can get quantitative test results. Analytical accuracy for solid melts is typically 2% to 5% RSD (relative standard error) and for fluid inclusions 10% to 30% RSD. Some of the complex systems of LA ICPMS can cause fractionation and quality disturbances. For the fractionation effect, it can be reduced by using short-wavelength lasers that generate small particles and by using He as the carrier gas; for mass interference,