Trace elements in a Pliocene-Pleistocene lignite profile from the Afsin-Elbistan field, eastern Turkey

We present the results of proximate and ultimate analyses, mineralogical de termination, and trace element analysis of a lignite profile from the Afsin -Elbistan field (eastern Turkey). The lignite, which developed during the P liocene-Pleistocene transition under freshwater lacustrine conditions, cont ains white gastropod (Planorbidae) shells composed of calcite and a little aragonite. Other identifiable mineral constituents, analyzed by X-ray powde r diffraction, include quartz, pyrite, clay minerals, and rare feldspars. P etrographical studies demonstrate the immature nature of these lignites and very low degree of compaction during diagenesis. The mean concentrations o f trace elements in the lignite, determined by inductively coupled plasma m ass spectrometry (ICP-MS) show relative enrichment in Mo (avg. 20 ppm), W(a vg. 15 ppm) and U (avg. 25 ppm) when compared to the global range for most coals, while the others (Ti, P, Sc, Be, Mn, Co, Cu, Zn, Ga, As, Rb, Sr, Zr, Nb, Cs, Ba, Y, Ta, Tl, Pb, Bi, Th, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu) fall within their global ranges. Many of the trace elements sh ow a good correlation with the ash yield, implying an inorganic affinity Ho wever Mo and Sr show a negative correlation with the ash yields and are tho ught to be organically associated. A lack of correlation of U with either t he ash yield or the total sulfur content, together with its relative enrich ment, suggests secondary mobility of this element.