摘要
本文通过该区火山岩的岩石化学特征分析和研究，确定了此火山岩的碱性程度为碱性─钙碱性，岩石系列为高铝玄武岩系列，拉斑玄武岩系列及碱性玄武岩系列，求得钙碱指数为52，属张性环境，并且在TAS图上样品落入玄武岩区及流纹岩区，在火山岩DI频率曲线图上表明具有大陆拉张的双峰式特点，并进而得出该区早二叠世卡拉岗组火山岩为双峰式大陆拉张构造环境的结论．
By analyzing and studying the volcanic rock's petrochemistry characterlstics of Saerbuer mountain,the author concludes that the alkalinity of this volcanic rock is alkaline and calcqlkaline suites and its rock series consist of high - alumina basalt, tholeiite and alkaline basalt. The calc-alkaline index of the suites is 52 which indicates the tensional tectonic setting. The dlstrlbution of these suites on the TAS diagram is the area of basalt and rhyolite,their DI frequence curve shows bimodal of rift valley. So the tectonic setting of the volcanic rock of Kalagang formation of Lower Permian setting in bimodal continentlal rift valley is confined.
关键词
早二叠世
卡拉岗组
火山岩
岩石化学
构造环境
Saerbuer mountanin
lower permian volcanic formation of kalagang
petrochemistry
tectonic setting
