Multielement analysis of continental and lacustrine ferromanganese nodules by WDXRF, TXRF, and ICP-MS methods. Intercomparison study and accuracy assessment.

Specific elemental and mineral composition of lacustrine and continental nodules differ substantially from silicate sedimentary rock, oceanic nodules, and crusts. The examination of this rock type requires study of the applicability of analytical methods to get accurate data on the elemental composition due to the lack of matrix-matched certified reference materials. In this study, multielement analysis of continental and lacustrine ferromanganese nodules was performed using various analytical methods. Samples were prepared as fused glasses and pressed pellets for wavelength-dispersive X-ray fluorescence, suspensions for total reflection X-ray fluorescence, and solutions after fusion for inductively coupled plasma mass spectrometry measurements. An intercomparison test was carried out to study the results using several analytical methods.

Wavelength dispersive X-ray fluorescence determination of major oxides in bottom and peat sediments for paleoclimatic studies.

The wavelength dispersive X-ray fluorescence method was applied to identify the distribution of major oxides within bottom and peat sediments containing organic matter of up to 70 wt.%. Samples were prepared as glass beads by fusing with lithium metaborate. The accuracy of results was assessed by flame photometry, spectrophotometry, and flame atomic absorption techniques. The proposed technique requires a sample weighing only 110 mg, which allows to analyze each centimeter of core collected at high-mountainous sites with undisturbed environment and eventually achieve uniquely high resolution of paleoclimatic reconstructions of global and regional climatic and environmental changes.