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Portable X-Ray Fluorescence (pXRF)

Overview

Thumbnail image of Portable X-Ray Fluorescence Portable X-ray fluorescence (pXRF) is analytically useful for a subset of elements whose abundances are high enough for detection and that produce X-rays sufficiently energetic for quantifiable analysis. When X-ray radiation from the instrument’s X-ray tube excites atoms within a sample, those atoms emit characteristic fluorescent X-rays that are detected by the instrument’s detector. The energy of the emitted X-rays is unique to each element, allowing for elemental identification based on the measured energy spectrum. Elements from magnesium (Mg) to uranium (U) can be detected.

Instrument Make and Model

Bruker AXS Tracer 5G

Estimated Measurement Time

  • Sample Measurement: ~3–5 mins/measurement

Quantity of Sample Material

1 cm2 or larger flat surface, equivalent to approximately 15–25 g powdered material

Principles & Analytical Capabilities

The Bruker Tracer 5G, which employs a rhodium X-ray source, operates in air, under helium purge, or in vacuum measurement atmospheres which allow for improved sensitivity for light elements like Na, Mg, Al, Si when helium or a vacuum is used.

This list of elements varies somewhat with rock type but commonly includes K, Ca, Ti, V, Cr, Mn, Fe, Ni, Zn, Cu, Rb, Sr, Y, and Zr. S and P are also quantitatively accessible at higher concentrations, as may be encountered in sulfate-, sulfide-, or phosphate-rich lithologies. The unit has the capability to measure both sediment and hard rock cores, as well as powders. The instrument includes an X-ray safe enclosure to measure powders.

Users may request specific pXRF standards for their analyses. We maintain a variety of standards suitable for rock and sediment analysis.

The instrument has integrated software (ARTAX and EasyCal) that support real-time spectral analysis and custom calibration development.

Data Generated

Data components:

  • Elemental raw data (unitless) can be generated for: Ag, Al2O3, As, Au, Ba, Bi, Ca, Cd, Ce, Cl, Co, Cr, Cu, Fe, Ga, Hf, Hg, K2O, La, MgO, Mn, Mo, Nb, Ni, P, Pb, Pt, Rb, Rh, S, Se, SiO2, Sn, Sr, Ta, Te, Th, Ti, Tl, U, V, W, Y, Zn, Zr

Data files:

  • XRF Results (XLSX): tabular file of spectra for all measurements and element concentrations (if standards used)

Raw files:

  • GeoExploration (TSV): tabular file of spectral data (energy v. counts) for each measurement. Elemental results reported in weight %.
  • GeoExploration (PDZ): instrument file with spectra and element concentrations for each measurement

Data Example

Graph of portable X-ray fluorescence geochemistry data of section half measurements from Hole U1612A of IODP Expedition 402 in the Tyrrhenian Sea.
Portable X-ray fluorescence geochemistry data of section half measurements from Hole U1612A of IODP Expedition 402 in the Tyrrhenian Sea.1

Procedures & Manuals

References

1  Malinverno, A., Zitellini, N., Estes, E. R., Abe, N., Akizawa, N., Bickert, M., Cunningham, E. H., Di Stefano, A., Filina, I. Y., Fu, Q., Gontharet, S. B. L., Kearns, L. E., Koorapati, R. K., Lei, C., Loreto, M. F., Magri, L., Menapace, W., Morishita, T., Pandey, A., … Zhao, X. (2025). IODP Expedition 402 Portable X-ray fluorescence (p-XRF) [Data set]. International Ocean Discovery Program. https://doi.org/10.5281/zenodo.15238667