The Composite Character of Regional Crustal Sm-Nd Isotopes and Their Implication for Qinling-Dabie Orogenic Belt

• 责任者：Hou Guangshun (College of Resources and Environments ; Henan Polytechnic University ; Jiaozuo 454000 ; China) ; Cao Shukai
• 刊名：Gansu Geology
• 出版年：2010
• 卷期：19(1)
• 关键词：地壳 ; crust ; 同位素组成 ; isotope composition ; 钐—钕计时 ; Sm-Nd dating ; 秦岭 ; Qinling Mountains ; 大别山 ; Dabie Mountains
• 页码：p.15-20
• 图表：5 illus., 58 refs.
• 分类号：0600
• issnNo：ISSN1004-4116
• isbnNo：CN 62-1191/P

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.