摘要
通过对岩石学、地球化学元素特征的分析,得出王家庄中二叠世玄武质火山熔岩属钙碱性系列,其轻稀土相对富集,重稀土相对亏损,具不明显的负铕异常,表明岩浆分异较强,具有早期岩浆的特点.微量元素Cr和Ni表现为明显的负异常,Sc和Mn为弱负异常,符合板内火山岩的特点.结合构造环境判别图解,推测早—中二叠世,该区发生了深部裂陷,形成了局部小规模的基性—超基性火山喷发.
It has been shown that the basaltic volcanic lavas in Wangjiazhuang belong to calc-alkalic basalts by the analysis of the petrology and geochemical elements. It is also found that its LREE are rich, but the HREE are relatively poor, which has negative Eu anomalies inconspicuously. Thus it shows the character of high magmatic differentiation of early magma. Trace elements Cr and Ni shows significant negative anomaly, and Sc and Mn show a weak negative anomaly, which are accord with inside volcanic character. With the combination of structural environment discrimination diagram, it is conjectured that there was a big rift happened in early middle permian which led the local small-scale basic and ultrabasic vulcanian eruption formation.
出处
《宁夏工程技术》
CAS
2014年第4期299-301,共3页
Ningxia Engineering Technology
关键词
火山岩
构造环境
大陆板内
volcanic rock
tectonic environment
continental intraplate setting
