In-Situ Parts-Per-Million Analysis of Marine Sediments by X-Ray Fluorescence Techniques

An energy-dispersive X-ray fluorescence analyser has been applied to the in-situ elemental analysis of marine and freshwater sediments. This technique allows upwards of 20 elements to be quantitatively measured to the 10 ppm level at water depths to 300 ft. The analyzer system consists of a solid cryogen-cooled Si(Li) X-ray detector with a 20 mil Be window, a 50 mCi¹⁰⁹Cd excitation source, and an analyzer/computer system for data storage and manipulation. Details of the detector system, the actual in-situ spectra, and the recorded data with respect to the detection of pollutants at existing environmental concentrations are discussed. The system response illustrates the usefulness of the technique for rapid environmental pollutant studies and mineral exploration of the marine sedimentary materials.