中朝板块北缘乌华敖包地块Sm－Nd同位素等时线年龄及其意义  

Sm-Nd ISOCHRON AND SIGNIFICANCE OF THE WUHUAOUBAO BLOCK IN NORTHERN MARGIN OF SINO-KOREAN PLATE

作　　者：徐备[1] 陈斌[1] 张臣[1] 白志强[1] 王宏伟 张强 

机构地区：[1]北京大学地质学系

出　　处：《地质科学》1994年第2期168-172,共5页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：霍英东教育基金会青年教师基金;地质矿产部填图项目

摘　　要：内蒙苏尼特左旗西南马华敖包地块绿泥绿市阳起片岩的Ｓｍ－Ｎｄ同位素全岩等时线年龄为１９１０±７２Ｍａ，表明这个位于中朝板块北缘古生代造山带内的地块属早元古代。样品的εＮｄ（ｔ）值为３．８７－４．０７，属中等─弱亏损地馒型，其构造背景为过渡性大陆边缘。uhuaoubao block which located in the early Paleozoic orogenic belt of northern margin of the Sino-Korean Plate, consists of guesses, quartz-schists, marble and chlorite epidote actinolite-schists. Four whole-rock samples from the actinolite-schists have been analysed. A Sm-Nd isochron of 1910±72 Ma has been determined and been used as an igneous age of the actinolite-schists. The date suggests that the Wuhuaoubao block belongs to an early Proterozoic block. εNd(t) values of the four samples are from 3.87 to 4.07, which give a proof of that the block formed in a transitional continental margin.

关 键 词：等时线 古地块 钐 钕 同位素 

分 类 号：P597[天文地球—地球化学]