云南北衙矿区富碱斑岩正长石和白云母的^(40)Ar-^(39)Ar年龄  

^(40)Ar-^(39)Ar DATINGS OF ORTHOCLASE AND MUSCOVITE FROM ALKALI-RICH PORPHYRIES IN THE BEIYA MINE, YUNNAN

作　　者：应汉龙[1] 蔡新平[1] 

机构地区：[1]中国科学院地质与地球物理研究所,北京100029

出　　处：《地质科学》2004年第1期107-110,共4页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家重点基础研究项目 (编号 :G1 9990 43 2 0 0 )

摘　　要：云南北衙矿区石英正长斑岩岩体在空间上与金、铅锌矿体共生。红泥塘岩体地表岩石正长石的40 Ar 39Ar坪年龄和等时线年龄为 2 5 89± 0 1 3Ma和 2 5 72± 0 7Ma ,万洞山岩体地表以下 382m钻孔中岩石的正长石坪年龄和等时线年龄为 2 5 5 3± 0 2 5Ma和 2 5 5 0± 0 0 7Ma,分别为两个岩体的形成年龄。但是 ,万洞山岩体地表团块状白云母的坪年龄和等时线年龄为32 5 0± 0 0 9Ma和 32 34± 0 0 4Ma ,为白云母的结晶年龄 。The Quartz syenite porphyries were spatially closely associated with gold and lead zinc ore bodies in the Beiya mine, Yunnan. 40 Ar 39 Ar plateau and isochronal datings of the orthoclase from surface outcrop of the Hongnitang quartz syenite prophyry yielded 25.89±0.13 Ma and 25.72±0.7 Ma respectively and those of the orthoclase from drill core of the Wandongshan quartz syenite prophyry, 382 m below the surface,yielded 25.53±0.25 Ma and 25.50±0.07 Ma. These ages were crystallizing ages of the host intrusions. The 40 Ar 39 Ar plateau and isochronal ages of muscovite conglomeration from surface outcrop of the Wandongshan quartz syenite prophyry were 32.50±0 09 Ma and 32 34±0.04 Ma respectively, representing crystallizing age of muscovite and probably also the age of the host rock.

关 键 词：富碱斑岩 正长石 白云母 ^40AR-^39AR年龄 成岩时代 

分 类 号：P597[天文地球—地球化学]