Apsorption units at wavenumbers and mineral content of several samples

In combination with other indicators, they contribute to the understanding of changes in sediment sourcing as well as in weathering and depositional processes. Fourier transform infrared spectroscopy (FTIRS) spectra contain information on mineralogical composition because each mineral has a unique absorption pattern in the mid-IR range.

Although easily obtained, FTIR spectra are often too complex to infer mineral concentrations directly. In this study, we use a calibration set of ca. 200 sediment samples conventionally measured using X-ray diffraction (XRD) in order to develop multivariate, partial least squares (PLS) regression models relating mineral contents to sediment spectra. Good correlations were obtained for the most common minerals (e.g. quartz, K-feldspar, illite, plagioclase, smectite, calcite).