摘要
银山矿区次火山岩主要可分为三类 ,1石英斑岩 2英安斑岩 3安山玢岩 ,它们均属于一套高钾钙碱性的中酸性花岗岩系列。矿区次火山岩中 ,Cu、Ag、Pb、Zn等成矿元素均高出同类岩性克拉克值 1倍以上 ,表明次火山岩与矿床形成关系密切。岩石地球化学特征表明 :矿区次火山岩属幔壳混合源 ,它们分别形成于幔源花岗岩区 ,板块碰撞前消减区 (消减的活动板块边缘 )和板块碰撞后隆起花岗岩区 ,这说明与矿床有关的火山活动发生在成熟的陆壳构造之上受太平洋板块向陆壳板块俯冲影响而形成的活动大陆边缘。
The subvolcanic rock in the Yinshan ore district can be classified into three types: ①quartz porphyry, ②dacite porphyry, ③andesite porphyrite. Their protolith belongs to a series of calcic alkaline intermediate acid granitoid. Rich Cu, Ag, Pb, Zn and other ore forming elements in the subvolcanic rock show that the rock is closely related to mineralization. Its petrologic geochemical characteristics indicate that it was mantle crust mixed type magma and formed in the mantle derived, pre plate collision (subducting active plate edge) and post collision uplift. It formed on an active continental margin in the late stage of early Yanshanian age.
出处
《大地构造与成矿学》
EI
CAS
CSCD
2000年第4期385-389,共5页
Geotectonica et Metallogenia
关键词
岩石地球化学
次火山岩
大地构造环境
微量元素
Petrologic geochemistry
subvolcanic rock
tectonic significance
Yinshan, Jiangxi
