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LA-ICPMS

Direct sampling of solids may be carried out using laser ablation. In this technique a high-power laser, usually a pulsed Nd-YAG laser, is used to vaporize the solid, which is then swept into the plasma for ionization. Besides not requiring dissolution or other chemistry to be performed on the sample, laser ablation ICPMS (LA-ICPMS) allows spatial resolution of 20-50 pm. Depth resolution is 1-10 pm per pulse. This aspect gives LA-ICPMS unique dit nostic capabilities for geologic samples, surface features, and other inhomogeneous samples. In addition minimal, or no, sample preparation is required. [Pg.629]

Alpha Spec. TIMS MC-TIMS ICPMS MC-ICPMS LA-ICPMS LA-MC- ICPMS SIMS... [Pg.52]

However, for many of the PGE, the concentrations in ores from Ni-Cu-PGE deposits were less than detection limit, laser ablation ICPMS (LA-ICPMS) offers three advantages over these techniques, namely 1) lower detection limits (ppb level), 2) accessibility, and 3) time-resolved analysis. [Pg.135]

LA-ICPMS has been used to determine the in-situ PGE content of base metal sulfides from PGE-rich reefs (e.g., Ballhaus et al. 2001 Holwell et al. 2007 Godel et al. 2008 Barnes et al. 2008). These studies demonstrate that all of the PGE, except Pt together with Au, are predominantly hosted by sulfides in solid solution and that pentlandite is a major carrier for Pd. The distribution of PGE in Ni-Cu-rich PGE deposits is less well-known. Huminicki et al. (2005) lasered sulfides from Copper Cliff Mine, Sudbury and calculated that the sulfides carried very little PGE and thus PGE were hosted mainly by PGM. We are furthering the study of Sudbury by investigating the distribution of PGE from Creighton Mine. [Pg.135]

Analytical Methods Whole rock and LA-ICPMS analyses were carried our at Universite du Quebec a Chicoutimi (UQAC). Sulfur was determined by combustion and IR analysis. Ni and Cu were determined by atomic absorption spectrophotometry after aqua regia digestion. Gold and PGE were determined by Ni-sulfide fire assay followed by Te co-precipitation followed by ICPMS. [Pg.136]

Acknowledgements We thank Vale-Inco for partially funding the project and with thanks to the technical support from Creighton Mine and the Exploration groups from Vale and Vale-Inco. We also thank D. Savard and R. Cox for their support with whole rock and LA-ICPMS analyses. This work was partially funded by the Canadian Research Chair in Magmatic Metallogeny. [Pg.138]

The main purpose of this work is to determine the IPGE contents of chromites from mantle podiform chromitites, from crustal stratiform chromitites and from various types of lavas. The analyses have been carried out by laser ablation inductively coupled plasma mass spectrometer (LA-ICPMS) which allows in-sltu determination of trace elements in chromite. [Pg.197]

Chromite major and minor element composition was determined by microprobe. The IPGE contents of chromite were determined at UQAC by a LA-ICPMS (Thermo X7 ICP-MS coupled to a New Wave Research 213 nm UV laser, 80 pm spot diameter, 10 Hz pulse rate, 0.3 mJ/pulse power). In addition to the IPGE other elements were monitored to control the nature of ablated material and the presence of included phases. [Pg.198]

Fig. 2. Backscatter electron images of a laurite grain included within a chromite from Stillwater chromitite H. b) enlargement of transient LA-ICPMS signal shown in a). Fig. 2. Backscatter electron images of a laurite grain included within a chromite from Stillwater chromitite H. b) enlargement of transient LA-ICPMS signal shown in a).
We have evaluated the IPGE (Os, Ir, Ru, Rh) content of chromite grains from chromitites and lavas in various tectonic settings using LA-ICPMS. [Pg.199]

Liu, J. et al. 2008. Zircon LA-ICPMS U-Pb dating of Hukeng granite in Wugongshan area,Jiangxi Province and its geochemical characteristics[J]. Acta Petrologica Sinica, 24(8), 1813-1822. [Pg.228]

LA-ICPMS analyses of pyrite and pyrrhotite in both spot and imaging mode (for 32 and 22 elements respectively) were completed on a New Wave 213nm solid-state laser microprobe coupled to an Agilent 4500 quadrupole ICPMS using the procedures otLarge etal. submitted). [Pg.305]

Fig. 1. LA-ICPMS maps of trace element variations in pyrite from a bedding parallel quartz-carbonate vein. The two textural types are a "spongy" discontinuous rim with higher Pb, Bi, Ag, Sb and Co contents than the massive core. Fig. 1. LA-ICPMS maps of trace element variations in pyrite from a bedding parallel quartz-carbonate vein. The two textural types are a "spongy" discontinuous rim with higher Pb, Bi, Ag, Sb and Co contents than the massive core.
I thank Zinifex Limited (now Oz Minerals) for financial support and for permission to present these results. D. Hicks, C. Archer and M. Skirka (Zinifex) and M. Jacobson (MRT) facilitated access to drill core and other data. P. Robinson, K. McGoldrick and S. Gilbert completed the XRF and solution ICPMS analyses and S. Gilbert provided assistance and advice on LA-ICPMS analyses. [Pg.307]

This chapter does not cover analytical techniques, and assumes that the reader is at least moderately familiar with the electron microprobe, ion microprobe, and laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS), as well as with the distinction between X-ray mapping and spot analysis by electron microprobe. Mineral abbreviations are after Kretz (1983). [Pg.1493]

Peng R., Machado N., and Ludden J. (1993) Lead geochronology of zircon by laserprobe-inductively coupled plasma mass spectrometry (LA-ICPMS). Geochim. Cosmochim. Acta 57, 3479-3486. [Pg.1604]

One of the problems that has been noted in laser ablation is fractionation between the sample surface and the material removed. For any given sample type, certain elements will be preferentially removed, giving these elements a higher relative abundance in the material analyzed by the mass spectrometer. If fractionated, this material is not representative of the sample, and biased data results. Research has shown that LA-ICPMS with deeper UV wavelengths (e.g., 157 nm, 193 or 213 nm) results in less fractionation. A pulsed laser with short pulse widths—on the order of picoseconds to femtoseconds—provides even less fractionation. [Pg.404]

Laser-ablation, inductively coupled-plasma mass spectrometry (LA-ICPMS) is an instrumental technique in which a laser-ablahon cell and ophcal microscope supplant the spray chamber/nebulizer apparatus of a standard ICP-MS instrument. Subsamples of questioned material are ablated from a solid sample via laser (often a pulsed Nd-YAG tuned to 266 or 213 nm). Ablated specimens are transported in a stream of Ar to a plasma torch for ionization and mass discrimination as per solution ICP-MS. Only minimal sample prep is required, and few restrictions are placed on the nature of questioned solid samples (Brundle et al. 1992 Vickerman 1998). While laser spot sizes can be reduced to several micrometers, sensitivity is degraded as a result, and usual spatial resolutions are on the order of 10-100 pm. Matrix-matched standards are also necessary for accurate trace-element and isotopic quantitative analyses in LA-ICPMS. Depending on the quality of such primary standards, LA-ICPMS accuracies are typically 1-10%, with limits-of-detection in the parts-per-billion (ppb) range (O Table 62.1). [Pg.2869]

Cocherie, A., Robert, M., Guerrot, C. (2005a) In situ U-Pb zircon dating using LA-ICPMS and a multi-ion counting system. Goldschmidt Conference, May 20-24, 2005, Moscow, ID. [Pg.704]

Cucina, A., Neff, H., Tiesler, V. (2005) Detecting provenience of African-origin individuals in the colonial cemetery of Campeche (Yucatan) a new approach using trace elements and LA-ICPMS. In Laser Ablation JCP-MS in Archaeological Research, edited by Speakman, R.J., Neffi H. Albuquerque University of New Mexico Press, pp. 187-197. [Pg.839]

A wish list of the main requisites that a technique should fulfill for its use in elemental archaeological research would certainly include the following aspects (1) nondestructive or minimally destructive nature (2) minimal sample preparation, regardless of the type of sample targeted (3) potential to achieve simultaneous multielemental data for major, minor, and trace elements in a straightforward way (4) capabilities for isotopic analysis and (5) potential to provide spatially resolved information, laterally, and in depth. Nowadays, the technique that complies with all of these requirements to the largest extent is laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS). [Pg.859]

The use of LA-ICPMS was first reported by Gray in 1985, who started evaluating a ruby laser for that purpose [1]. However, its application has risen signifi-... [Pg.859]

FIGURE 39.1 The number of archaeological pubhcations during the last years of the current decade. The bars represent the number of journal publications that have reported the use of LA-ICPMS for archaeological research during the last 18 years. The dots indicate the number of those papers that focus on isotopic analysis. Source ISI Web of Science. Papers that appeared in proceedings and book chapters have not been included. [Pg.860]

The goal of this chapter is to discuss the potential of LA-ICPMS for archaeological research. The basic operating principles of this technique, together with its capabilities and limitations, will be discussed in detail. The main applications developed by researchers in this field will be reviewed in a tutorial way, in order to highlight the most relevant parameters that significantly affect the performance of LA-ICPMS, in the hope of making the development of new methods in this field easier. [Pg.860]

This technique uses a high-energy laser beam to remove a minute amount of the sample under investigation. A typical scheme that shows the basic components of an LA-ICPMS instrument is shown in Figure 39.2. The sample is typically placed inside a closed ablation chamber, and the laser beam is usually focused onto the surface. Generally, the ablation cell is mounted on a software-controlled translation stage that can be steered in all three spatial directions. Moreover, the cell is monitored by a video camera and/or microscope, such that it is possible to select the exact location for ablation with an accuracy of a few micrometers. [Pg.860]

FIGURE 39.2 Schematic setup of a typical LA-ICPMS instrument. [Pg.860]

This process shows an apparent simplicity, as stated by Gunther and Hattendorf [12], which might be one of the reasons for the increasing popularity of this technique. In theory, one just needs to put a sample inside the chamber, fire a few laser pulses, and a portion of the sample will be vaporized and swept into the inductively coupled plasma mass spectrometer (ICPMS). In a few seconds, the corresponding transient signals that can provide qualitative, quantitative, and isotopic information for tens of elements appear on the screen. Examples of typical LA-ICPMS signal profiles are shown in Figure 39.3. [Pg.861]


See other pages where LA-ICPMS is mentioned: [Pg.136]    [Pg.137]    [Pg.197]    [Pg.306]    [Pg.18]    [Pg.177]    [Pg.840]    [Pg.842]    [Pg.844]    [Pg.138]    [Pg.140]    [Pg.142]    [Pg.257]    [Pg.616]    [Pg.404]    [Pg.404]    [Pg.2870]    [Pg.860]    [Pg.860]    [Pg.860]    [Pg.861]    [Pg.861]   


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