摘要
本文选择区内4个花岗岩体,对其中REE、Rb、Sr、Ba、Sc等痕量元素的分配特征进行研究。这些岩体产于不同地区,形成不同时代,大致可以代表区内主要类型的花岗岩类岩石。研究表明,在四类花岗岩中,随着岩石SiO_2含量和分异系数DI值的增大,岩石的Rb/Sr值相应增大,LREE/HREE、La/Yb、K/Rb值相应减小,意味着岩石的痕量元素分配与岩石的主元素成分间具有一定的相关关系。对比清湖和扶溪岩体REE在矿物之间的分配特征得知,除矿物的晶体化学性质是决定REE分配的主要因素外,REE在矿物之间的分配与矿物的晶出顺序也有关系。
Granitoids are widely spread in the Nanling Region of China. Four rockbodies in the region have been studied for their REE,Rb,Sr, Ba and Sc distributions. The four rockbodies occurred in different locations and are characterized as being different in forming age and rock type. The rock types are presented as follows: Qinghu monzonite, Guangxi; Fuxi granodiori-te, Guangdong; Jiufeng monzonitic granite, Hunan; and Zoudong K-feldspar granite. From, the major and trace element distributions in these granitoids it is clearly shown that Rb/Sr ratios in the rocks tend to increase with increasing SiO2 content and differentiation index(DI), but LREE/HREE, La/Yb and K/Rb ratios tend to decrease, suggesting a correlation between trace element distribution and major element composition for the granitqids. The distribution characteristics of trace elements in each of the rockbodies is discussed in detail. It is evidenced that the REE distribution is closely related to the sequence of crystallization for the minerals, and also to the petrochemical types of these granitoids in addition to their crystal chemistry.
出处
《地球化学》
CAS
CSCD
北大核心
1992年第4期333-345,共13页
Geochimica
基金
国家自然科学基金
