武当地块基性岩墙群的Sm-Nd定年及其相关问题讨论  

Sm Nd Dating of Basic Dykes from Wudang Block and a Discussion of Related_Questons

作　　者：周鼎武[1] 张成立[1] 刘良[1] 王居里[1] 刘颖宇[1] 张宗清[2] 

机构地区：[1]西北大学地质系 [2]中国地质科学院地质研究所

出　　处：《地球学报（中国地质科学院院报）》1998年第1期25-30,共6页Acta Geoscientia Sinica

基　　金：国家自然科学基金

摘　　要：武当地块是卷入南秦岭构造带的前震旦纪基底岩块，该基底岩块中广泛发育变形变质的基性岩墙群，获得岩墙群的ＳｍＮｄ全岩等时年龄为ｔ＝７８２±１６４（２σ）Ｍａ，ＩＮｄ＝０．５１１７１±１６（２σ），εＮｄ（ｔ）＝＋１．５±１．０。据此并综合区域地质实际，对南秦岭元古代古陆块的存在及其裂解等相关问题进行了讨论。The Wudang Block is a Presinian basement block involved in the South Qinling belt,in which a large number of deformed and metamorphosed basic dykes are widely developed.We have determined isochron dating of Sm Nd whole rock: t =782±164(2σ)Ma, I Nd =0.51171±164(2σ),ΣNd( t )=+1.5±1.0.Besed on the result,the questions related to basement signature of South Qinling and rifting of ancient continental block in Neoproterozic,character are also discussed with original geology.

关 键 词：武当地块 基性岩墙群 钐 钕 同位素测年 

分 类 号：P597.3[天文地球—地球化学] P583[天文地球—地质学]