In situ trace element determination of carbonates by LaserProbe Inductively Coupled Plasma Mass Spectrometry using nonmatirx matched standardization

Journal Article · Tue Mar 01 00:00:00 EST 1994 · Geochimica et Cosmochimica Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(94)90563-0· OSTI ID:7107669

Feng, Rui ^[1]

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1. Universite de Montreal, Quebec (Canada)

The LaserProbe Inductively Coupled Plasma Mass Spectrometry (LP-ICP-MS) has shown great potential to precisely and quickly determine trace element compositions of minerals in situ at a scale of [le]60 [mu]m. However, standardization is complicated, due to the lack of matrix-matched, homogeneous mineral standards. In this study, a nonmatrix matched calibration standard, the NIST 612 silicate glass, was employed to determine Sr, Y, Ba and REE concentrations in calcite and dolomite grain mounts. Using [sup 43]Ca as an internal standard, the results demonstrate that it is not essential to have a matrix-matched mineral standard by LP-ICP-MS. Routine limits of detection are [approx] 10 ppb for REEs, and [approximately] 200 ppb for Sr, Y, and Ba, depending on laser operating conditions. Evaluation of precision and best within-grain precision (determined from several LP sampling pits within an individual mineral grain) is considered to represent the maximum analytical error, and is generally <5% RSD for REEs [ge] 1 ppm, <10% RSD for REEs between 0.1-1 ppm, and [approx] 15-25% for lower concentrations. Nonmatrix matched standardization for quantitative analysis can successfully be used, because the small size laser probe ([approx] 10 [mu]m) used in this study can generate much higher power density than the conventional size laser beam. At high power density, the sample ablation mainly results from plasma plume expansion induced by the laser, not from absorption of the laser bean and related thermal vaporization, as for conventional, low power density laser analysis. The plasma plume expansion as a major ablation process permits the ablation of even those materials usually transparent to laser (e.g., calcite). This technique can be applied to the analysis of trace elements of carbonates in thin sections, grain mounts, and rock or mineral chips, thus avoiding extensive sample preparation with significant implications for studies of near-surface and environmental processes.

• OSTI ID: 7107669
• Journal Information: Geochimica et Cosmochimica Acta; (United States), Vol. 58:6; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
BARIUM
ABUNDANCE
CALCITE
ICP MASS SPECTROSCOPY
DOLOMITE
STANDARDIZATION
RARE EARTHS
STRONTIUM
YTTRIUM
CALCIUM 43
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METALS
CALCIUM ISOTOPES
CARBONATE MINERALS
ELEMENTS
EVEN-ODD NUCLEI
INTERMEDIATE MASS NUCLEI
ISOTOPES
MASS SPECTROSCOPY
METALS
MINERALS
NUCLEI
SPECTROSCOPY
STABLE ISOTOPES
TRANSITION ELEMENTS
400102* - Chemical &amp; Spectral Procedures