摘要
对秦岭—大别造山带大量Nd同位素资料进行统计,获得了该地区陆壳基底和区域花岗岩类的147Sm/144Nd平均值,分别为0.136和0.108。基于区域资料获得的二阶段亏损地幔模式年龄(T2DM)比用147Sm/144Nd=0.118做参数的计算结果要普遍偏老,两种结果的差异随着模式年龄的偏老明显偏大。本研究获得的该区域地壳147Sm/144Nd组成特征与元素丰度资料之间存在较大差异,结合稀土元素综合对比,表明前人获得的该区域元素丰度资料偏酸性。
It is of important significance to calculate the two stage depleted mantle model age of Nd isotope for crustal residence age. But so far the important parameter ^147Sm / ^144Nd has not been determined. The mean ^147Sm / ^144Nd of crustal base and regional granite are 0.136 and 0.108 respectively on the basis of a large amount of Nd isotope in Qinling-Dabie orogenic belt. The two stage depleted mantle model age using regional data is older than that of ^147Sm / 144Nd=0.118. There is some difference on ^147Sm / 144Nd compositional features and the data of element abundance in Qinling-dabie orogenic zone, and this indicates that the regional crust is probably more evolved than earlier result from the REEs.
出处
《甘肃地质》
2010年第1期15-20,共6页
Gansu Geology
基金
河南理工大学博士基金资助
