Geochemistry characteristics of rare earth elements in the Keluke Formation coal from Shihuihou Area,Qinghai

This paper presents the data on the mineral composition, major and rare earth elements and ytterbium (REY) in coal from the Keluke Formation in the northern margin of Qaidam Basin.The optical microscope, inductive coupling plasma mass spectrum, X-ray and XRF were applied for studying the contents, distribution characteristics, occurrence state, distribution pattern and facies significance of the major and rare earth elements.The results indicate that the content of rare earth elements is higher than that of Chinese coal, world coal and coal in the United States.The REY in the Keluke Formation's coal mainly occur in inorganic forms, mainly from terrigenous debris, and the part of rare earth elements originate from the plants or are affected by the micro-sedimentary environment.Through the study of geochemical parameters of rare earth elements, it is found that the light and medium rare earth elements are obviously enriched in the coal, and the rare earth elements in the coal seams are related to the acidic marsh water medium conditions and formed under the reducing conditions.Meanwhile, the rare earth elements in the coal seams are mainly received terrestrial control with basic igneous rock as the main source rock.