REE geochemistry of Devonian Stratum, in the Dachang Ore District, Guangxi, South China

In the Dachang ore district, it is Devonian stratum that acts as the important wall rock, which is close to the Sn polymetallic deposit. Based on the REE chemistry, the characteristics of Devonian and its significance to mineralization were discussed. The total REE content has a large variation (being 2.9 to 318.77), LREE lies between 2.26 to 298.13, HREE lies between 0.64 to 20.64, the ration of LREE/HREE lies between 3.53 to 14.44, LaN/YbN lies between 0.47 to 3.18, δEu lies between 0.27 to 7.69, δCe lies between 0.52 to 1.01 (the average value being 0.71). The shape of North American shale normalized curve is roughly similar, which suggest the same feature for Devonian. In the whole, on the basis of the REE content, it could be divided into two types. The first is characterized by positive Eu anomaly (being higher than 0.1), the other kind is characterized by negative Eu anomaly (being lower than 0.1).