摘要
在La/Sm-La协变图解中,基性-超基性岩浆系统成岩过程呈现两种不同的排列方式:一种为水平线;另一种为斜线。由于花岗岩岩浆系统中总分配系数不能忽略不计,因而其产物在La/Sm-La图解中的协变图形,一方面有别于基性-超基性岩浆系统,另一方面具多解性。因此,对这种协变图必须结合地质关系进行综合解释。
Theoretical calculations and case studies show that La/Sm-La covarianceplots for petrogenetic processses in an ultrabasic-basic magmatic systemarrange either in a horizontal line or in a inclined line. Owing tounnegligible rock/melt distribution coefficients of the granite system theirLa/Sm-La covariance plots are different from those of the ultrabasic-basicsystem and have multiplicity of solutions. Explanation of these plots must betaken into full consideration of their geological relations.
