摘要
甘肃省北祁连西段黑下佬二长花岗岩是加里东造山期同碰撞期产物,是以岩墙扩张机制形成的被动就位岩体,为下地壳部分熔融形成的花岗岩岩浆经分异结晶作用形成的I型花岗岩。按其副矿物组合特征,相当于磁铁矿系列,具有轻稀土富集的右倾式稀土元素配分形式,岩石的δ18OSMOW值与I型花岗岩的一般特征相符,岩石的微量元素蛛网图特征与同碰撞期花岗岩相似。
Heixialao monzonitic granite in the west sector of northern Qianlianshan was formed during syn-collision by passive emplacement of dyking. It is an Ⅰ-type granite that was formed by differential crystallization of a granite magma derived from partial melting of the lower crust, which corresponds with ilmenite series in accessory mineral assemblage. It has a right-inclined, enriched-LREE REE distribution pattern. The δ18OSMOW of the granite is analogical with that of Ⅰ-type granite. It is similar to syn-collision granites in the trace element spider diagram.
出处
《地质调查与研究》
2007年第2期110-114,共5页
Geological Survey and Research
基金
国土资源大调查项目(1212010534102)资助
关键词
同碰撞花岗岩
地质特征
北祁连
syn-collision granite
Geological Characteristics
Northern Qianlianshan
