腾冲火山岩同位素地球化学研究  

Geochemistry of the Isotopes in the Volcanic Rocks in Tengchong, China

作　　者：周真恒[1] 向才英[1] 杨海林[2] 

机构地区：[1]云南省地震局,昆明650041 [2]昆明理工大学,650093

出　　处：《地震研究》2000年第2期194-200,共7页Journal of Seismological Research

基　　金：云南省科技攻关项目

摘　　要：研究了腾冲火山岩的Pb、Sr、Nd同位素地球化学特征 :该区火山岩具高的2 0 6 Pb 2 0 4Pb、2 0 7Pb 2 0 4Pb、2 0 8　Pb 2 0 4Pb、87Sr 86 Sr和低的1 4 3Nd 1 4 4 Nd值 ,所反映的岩浆源区为EMⅡ。模拟计算表明 :地幔源中下地壳组分(含少量大洋沉积物 )占 2 0 % ,地幔源相当于榴辉岩组成。In this paper, the geochemical characteristics of Pb, Sr and Nd isotopes in the volcanic rocks in Tengchong have been studied. That the volcanic rocks have the high 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, 208 Pb/ 204 Pb and 87 Sr/ 86 Sr and low 143 Nd / 144 Nd values reflects that their magmas originate from the enriched mantleⅡ(EMⅡ). Simulating computation shows that in the mantle source, the lower crust component (including a few oceanic sediments) accounts for 20% and the mantle source matches the eclogite.

关 键 词：铅铜位素 锶同位素 火山岩 腾冲地区 地球化学 

分 类 号：P588.14[天文地球—岩石学] P595[天文地球—地质学]