激光剥蚀ICP-MS法测定盐类矿物单个流体包裹体的成分

Composition Determination of Single Fluid Inclusions in Salt Minerals by Laser Ablation ICP-MS

采用纯石英毛细管人工流体包裹体作为校准样品,通过对系列人工流体包裹体激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)测试分析,初步建立了LA-ICP-MS分析盐类矿物单个流体包裹体化学组成的分析方法流程以及包裹体中8种常见元素K,Ca,Mg,Sr,Rb,B,Li和Br的校准曲线。其中,K,Ca,Mg,Sr,Rb和Li的校准曲线的相关系数R2>0.9991;相对标准偏差为0.1%～6.2%;B和Br的校准曲线的相关系数R2稍低,分别为0.9910和0.9618;相对标准偏差4.1%～29.6%。校准曲线结果表明,建立的盐类矿物单个流体包裹体原位ICP-MS多元素定量分析方法是可行的,并且是较准确的。本方法简便、快速、灵敏度高。运用本方法对新疆罗布泊石盐和石膏矿物流体包裹体进行了测试,取得了满意的结果。

The chemistry of primary fluid inclusions in salt minerals can be well used to study brine composition change and environment evolution of the salt lake. In this study, artificial fluid inclusions in quartz microcapillary tubes were used as calibration samples. An initial analytical processes of composition determination of single fluid inclusions in salt minerals was established by laser ablation ICP-MS, and the calibration curves of the eight common elements （K, Ca, Mg, Sr, Rb, B, Li, Br） in salt mineral inclusions were obtained. The correlative coefficient R2 of the calibration curves were over 0. 9991, and the relative standard deviations were 0.13%-6.2% for K, Ca, Mg, Sr, Rb, Li. While R2 of the calibration curves was 0. 9910 and 0. 9618 for B and Br respectively, the relative standard deviations were 4. 1% -29.6%. The results indicated that the analytical method using LA-ICP-MS for the determination of the multi-element component in salt mineral fluid inclusions is feasible and accurate. This method has advantages of simplicity, speediness, high sensitivity, etc. It is suitable for the composition determination of single fluid inclusions in halite and gypsum in Nop Nur.