Rapid whole-rock mineral analysis and composition mapping by synchrotron X-ray diffraction

Abstract

We show that 25–140 keV X-rays from high-brilliance synchrotron sources can penetrate through 25 mm of intact rock. Powder diffraction patterns are obtained rapidly by energy-dispersive detection. Data acquisition time is reduced by a large factor (say 10²–10³) compared with standard laboratory powder diffraction methods. Data are presented on sedimentary rock cores and mineral standards. Full-pattern fitting is used for quantitative modal analysis of the composition. Using acquisition times of only 20 s for each pattern, we show the feasibility of line traverse (conveyor-belt) X-ray diffraction analysis and compositional tomography with sub-millimeter resolution.