摘要
近年来激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)应用于单个流体包裹体成分定量分析已成为研究流体包裹体的最佳手段之一。该实验过程和数据处理比较复杂,目前国内外采用的数据分析软件为一款基于MATLAB的SILLS软件,该软件主要是对矿物(锆石)、流体包裹体以及熔体包裹体LA-ICP-MS分析结果进行处理。本文以萤石流体包裹体LA-ICP-MS分析为例,阐述了样品制备与流体包裹体的优选方法,对流体包裹体片厚度以及单个流体包裹体的选取要求作了详细描述,对仪器参数设置、内外标样选取和剥蚀方法等进行了说明。基于SILLS软件采用尖峰消除的方法对待处理数据进行校正,对不同种类型的波峰进行峰宽的选取。在元素比值校正和等效盐度计算过程中,由于被测样品是萤石,Ca元素具有较高的背景值,选择以Na作为流体包裹体的内标元素,以Ca作为寄主矿物的内标元素对寄主矿物浓度进行计算,同时提出以电价平衡代替质量平衡进行等效盐度计算。以上方案提高了LA-ICP-MS分析单个萤石流体包裹体的准确性,有助于解释成矿流体来源和矿床成因等问题。
BACKGROUND:In recent years,laser ablation inductively coupled plasma-mass spectrometry(LA-ICP-MS)for quantitative analysis of single fluid inclusion components has become one of the best methods for studying fluid inclusions.Due to the low success rate of this experiment,it is of great help to improve the experimental success rate by standardizing the whole experimental procedure and correctly processing the experimental data.At this stage,the data analysis software used at home and abroad is a SILLS software based on MATLAB,which deals with the LA-ICP-MS analysis results of mineral(zircon,etc.),fluid inclusions and melt inclusion.OBJECTIVES:To help researchers properly operate the entire experimental process,and to detail the use of the SILLS software for improved LA-ICP-MS analysis of single fluid inclusion.METHODS:The fluorite fluid inclusions were analyzed by LA-ICP-MS at the James Cook University,and the data was processed using the SILLS software.The actual operation of the experiment was performed to discuss common problems during the experiment.RESULTS:The fluorite fluid inclusion LA-ICP-MS analysis was taken as an example to standardize the sample preparation and selection before the experiment.The instrument parameters were set in the experiment,the internal and external standard samples were selected,and the Straight Ablation method was used instead of the Stepwise Ablation method.At the same time,based on the SILLS software,the peak elimination and how to choose a reasonable peak width in different situations were explained.In the element ratio correction and the equivalent salinity calculation,since the sample to be tested was fluorite,the Ca element had a higher background value.Therefore,the host mineral concentration was calculated by using Na as the internal standard element of the fluid inclusion and Ca as the internal standard element of the host mineral.At the same time,it was proposed to calculate the equivalent salinity by replacing the mass balance with the charge balance.CONCLUSIONS:The above scheme improves the accuracy of LA-ICP-MS analysis of individual fluorite fluid inclusions and helps to more accurately explain the source of ore-forming fluids and the genesis of the deposit.
作者
李阳
邹灏
刘行
蒋修未
李蝶
LI Yang;ZOU Hao;LIU Hang;JIANG Xiu-wei;LI Die(College of Earth Sciences,Chengdu University of Technology,Chengdu 610059,China;State Key Laboratory for Mineral Deposits Research,Nanjing University,Nanjing 210046,China;Key Laboratory of Mineralization and Accumulation,Ministry of National Resources,Chengdu 610059,China)
出处
《岩矿测试》
CAS
CSCD
北大核心
2020年第2期300-310,共11页
Rock and Mineral Analysis
基金
国家自然科学基金项目(41702108)
内生金属矿床成矿机制研究国家重点实验室开放基金项目(2019-LAMD-K14)
四川省教育厅科研项目(2018CZ0009)
