Imaging Element-Distribution Patterns in Minerals by Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry (La-Icp-Ms)

Abstract

We demonstrate the application potential of laser-ablation -inductively coupled plasma -mass spectrometry (LA-ICP-MS) to map the distribution of major and trace elements in a variety of samples. The examples cover a wide range of elements, including the rare-earth elements (REE) and platinum-group elements (PGE). In order to test the capabilities of the technique, samples of different matrices were analyzed (i.e., carbonates, silicates and sulfides). The main obstacle to rapid processing of element-distribution maps by laser ablation was data processing. This has been overcome with the development of new software, such as IoLITE, and improved designs of the laser-ablation cells and refinements of commercially available laser systems. It is possible to obtain fully quantified concentration maps for single-matrix samples using parallel adjoining line-scans. Single spot-analyses will result in better precision and accuracy, but the geochemical images are superior to conventional laser-ablation spot-analysis because they reveal geochemical details that are not visible under the microscope and cannot be appreciated with single spot-analyses. In addition to providing spatial information, the individual line-scans that are used in the image acquisition offer the option to obtain quantitative results along any part of the scan. Using LA-ICP-MS imaging, our dataset reveals zoned REE distribution in garnet crystals, a heterogeneous occurrence of the PGE in sulfides, as well as the internal chemical structures in ooids with respect to conditions of growth.Keywords: imaging, trace elements, laser-ablation ICP-MS, sulfides, oolith, garnet. sommaIRENous démontrons ici le potentiel de l'analyse par ablation au laser avec plasma à couplage inductif et spectrométrie de masse (LA-ICP-MS) pour cartographier la distribution des éléments majeurs et en traces dans une variété d'échantillons. Ces exemples impliquent plusieurs éléments, y inclus les terres rares et les éléments du groupe du platine. Afin d'évaluer les capacités de la technique, nous avons choisi des échantillons ayant plusieurs matrices différentes (par exemple, carbonates, silicates et sulfides). L'obstacle principal à la production rapide de telles cartes de distribution par ablation au laser serait la réduction des données. La disponibilité d'un nouveau logiciel, IoLITE, et des affinements récents dans la conception de la cellule d'ablation sur les systèmes courants, ont permis de surmonter cet obstacle. Il est maintenant possible de construire des cartes de répartition d'éléments pleinement quantifiées là où les échantillons ont une seule matrice en utilisant des balayages linéaires adjacents. Une analyse à un seul point peut produire une meilleure précision et justesse, mais les images géochimiques fournissent un outil supérieur à l'analyse conventionnelle en révélant des détails invisibles au microscope ou impossibles à obtenir avec une série d'analyses ponctuelles. § E-mail address: tulrich@laurentian.ca En plus de fournir de l'information sur la disposi...

Applications of LA-ICP-MS in the elemental analyses of geological samples

“…As a consequence, LA-ICP-MS has been used in the geosciences not only as a single-spot analysis method, especially where trace element or isotope concentrations are required at high spatial resolution (e.g. the analysis of a single fluid/melt inclusion, a single zircon grain, or the zonation of a mineral) [2,4,5,9-16] or distribution analyses of elements and isotopes of rocks and minerals are required [17][18][19][20][21], but also for bulk analyses of rocks and soils [22][23][24][25][26][27][28][29].…”

Mapping of Sulfur Isotopes and Trace Elements in Sulfides by LA-(MC)-ICP-MS: Potential Analytical Problems, Improvements and Implications

“…LA-ICP-MS mapping has been applied to a variety of geological samples to study magmatic evolution [9], the distribution of platinum group elements (PGE) in sulfides [10], to develop solid standards [11], to understand substitutions and distribution mechanisms among element pairs [12,13], ore forming processes [14][15][16], and many other applications.…”

Quantitative mapping of trace elements in agate using LA-ICP-MS

“…Laser ablation (LA) system is powerful and versatile for in situ microsampling of solid materials including geological samples particularly when it is attached to ICP-MS (e.g., Jackson et al 1992;Norman et al 1996, Günther et al 1997Jeffries et al 1998;Niemax 2001;Heinrich et al 2003;Günther and Hattendorf 2005;Large et al 2009;Koenig et al 2009;Ulrich et al 2009). The development and application of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) have grown with a dramatic rate, and in situ analyses for elemental abundances and isotopic compositions are now performed routinely in numerous laboratories worldwide.…”

“…It is also possible with other microanalytical techniques such as ion microprobe, proton-induced X-ray emission (PIXE), and synchrotron X-ray fluorescence (Woodhead et al 2007;Ulrich et al 2009). In contrast to the above methods, LA-ICP-MS trace element mapping is the only technique performing at low limits of detection for a wide range of elements in a relatively short acquisition time.…”

“…In contrast to the above methods, LA-ICP-MS trace element mapping is the only technique performing at low limits of detection for a wide range of elements in a relatively short acquisition time. The application of quantitative element distribution maps using LA-ICP-MS has been accelerated with the development of analytical protocol and easy-to-use software such as Iolite (Woodhead et al 2007;Ulrich et al 2009).…”