| Abstract: | A radionuclide-excited energy-dispersive X-ray fluorescence (EDXRF) device has been used for geochemical mapping of soils over the Orberg deposit of the Kaiserstuhl carbonatite near Schelingen. About 500 samples were collected from an area of 0.2 km2. The mobile EDXRF equipment was used in field laboratories to determine twelve trace elements (Cu, Zn, As, Rb, Sr, Y, Zr, Nb, Ba, La, Ce and Pb) quantitatively, and the major components K2O, CaO, TiO2, MnO and Fe2O3 semiquantitatively. Additional information on bulk chemistry was obtained by determining the average atomic number from scattered radiation. An attempt is made to identify the different carbonatite subcrops in this area by use of trace element patterns and inter-element relationships. Since part of the survey area is covered with loess, relations and ratios between elements were used to estimate the dilution effect due to loess. |
