Journal
CHEMICAL GEOLOGY
Volume 453, Issue -, Pages 35-54Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.chemgeo.2017.01.023
Keywords
Portable X-ray fluorescence; Calibration; Major and minor oxides; Trace elements; Rock billets; Powdered rock; Powdered basalt; Powdered rhyolitic pumice
Categories
Funding
- NSF [EAR-1145127]
Ask authors/readers for more resources
Advances in portable X-ray fluorescence (pXRF) technologies have made such instruments an attractive choice for geologists who wish to collect chemical data in the field. The acceptance of pXRF data for research purposes such as, for example, petrogenetic studies by the geologic community has been hampered by a perception of poor quality. Here, we show that current-generation pXRF instruments can yield high-quality data when deployed either in the laboratory, or as a base-camp field instrument. We have developed four calibrations for major, minor and trace elements in geological materials using minimal sample preparation: one for the broad range of geologic compositions (0-100%SiO2) using rock powders, and three with an emphasis on volcanic rock samples: rock billets ranging from primitive basalt to rhyolite, basalt rock powder, and rhyolitic pumice powder. The calibrations use influence coefficients to correct for absorbance and secondary enhancement of one element by X-rays of other elements present in the sample. Nugget effects can have a significant influence over the determination of the concentration of elements such as Zr if proper care in sample homogenization is not taken. We evaluate data quality for each element in each calibration, and find that for several elements (Ti, Mn, Fe, Ca, K, P, Cr, Ni, Zn, Rb, Sr, Y, Zr, Nb), precision and accuracy approach those obtainable from full-size wavelength-dispersive XRF analysis. Maximization of data quality is achieved by matching of calibration material types and unknowns. (C) 2017 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available