REE geochemical characteristics of volcanic rocks in Zhejiang and Jiangxi provinces and their geological significance

Abstract

Based on the data of 64 samples, the REE geochemical characteristics of volcanic rocks in northern Zhejiang and eastern Jiangxi provinces are discussed in this paper. The REE distribution patterns in acid and intermediate-acid volcanic rocks in these areas display some similarities, as indicated by rightward-inclined V-shaped curves with negative Eu anomalies, which are parallel to each other. In addition, their REE parameters (ΣREE, ΣLREE/ ΣHREE, δEu,Ce/ Yb, La/ Sm, La/ Yb, etc.) also vary over a narrow range with small deviations. HREE are particularly concentrated in the volcanic rocks associated with uranium mineralization. The initial87Sr /86Sr ratio in the volcanic rocks is about 0.7056–0.7139. All these features in conjunction with strontium isotopic data indicate that the rock-forming materials come from the sialic crust. The REE distribution patterns and REE geochemical parameters of the volcanic rocks, as well as La/ Sm-La and Ce/ Yb-Eu/ Yb diagrams may be applied to the sources of rock-forming and ore-forming materials.