Distribution characteristic of rare earth elements of mudstone of Hebei plain area

The abundances of rare earth element ( REE) in 32 mudstone samples from Hebei plain area were deter- mined by inductively couple-plasma mass spectrometry (ICP-MS). The contents of the REE,geochemical parameters, geological significance,spatial distribution and distribution patterns were studied in this paper. The results are as fol- lows:compared with North American shale,the REE are obvious in the study area,and the REE content in the Shanxi Formation are higher than in the Taiyuan Formation. The correlation between ΣREE and external elements,like Ti,Ni, Pb,Rb,Ga,Cr and Zn is very good,which indicates that the REE is mainly supplied by terrigenous minerals. The de- positing rate,rare earth element and trace element ratios have obvious variation at sedimentary interface between the Taiyuan Formation and the Shanxi Formation,respectively,reflecting tectonic uplift in Huabei plain area.