Fig. 4. (A) Zinc K-edge extended X-ray adsorption fine structure (EXAFS) spectra of untreated and sequentially extracted soil samples from increasing profile depths and reference spectra (solid lines). Linear combination fit (LCF) spectra of the soil samples are offset for clarity (thin dashed lines). Details indicated by arrows are mentioned in the text. (B) Fourier transforms of the EXAFS spectra of soil samples and references (solid lines = magnitude; thin dashed lines = imaginary part). Vertical lines mark the approximate positions of the peaks for first shell O and S coordinated with Zn in the reference spectra.