公婆泉铜矿岛弧型含矿斑岩地质地球化学特征  

The ore-bearing porphyry at island-arc in the Gongpoquan Copper Deposit:its geology and geochemistry

作　　者：戴霜[1] 任育智 程彧[1] 高兆奎 张翔[3] 王方成[3] 

机构地区：[1]兰州大学西部环境教育部重点实验室,甘肃兰州730000 [2]甘肃有色金属地质勘查局,甘肃兰州730000 [3]中国地质大学工程学院,湖北武汉430074

出　　处：《兰州大学学报（自然科学版）》2002年第5期100-107,共8页Journal of Lanzhou University(Natural Sciences)

基　　金：国家科技攻关计划 (85 90 10 2 0 1);国家计划委员会科技招标 (G94 9170 1)资助项目

摘　　要：目前发现的斑岩型铜矿的含矿斑岩均产于陆相环境 ,公婆泉铜矿斑岩是目前为止发现的惟一产于海相环境的含矿斑岩 ,围岩沉积环境、岩石化学和地球化学研究表明 ,含矿次英安斑岩和花岗闪长斑岩产于海相环境 ,形成于水下 5 0 0～ 10 0 0 m,是中—晚志留纪哈萨克斯坦板块向 (南 )It is discovered for the first time that the ore-bearing porphyry has been developing under the sea in the Gongpoquan Copper Deposit. The ore-bearing porphyry is of dacito-porphyry and granodiorito-porphyry. They intrude in the middle of marine sedimentary-volcanic formation of Gongpoquan group,which comprises of the quartz trachyte,rhyolite,andesite and andesitic tuff and bears the intercalation of lensoid carbonates and banded magnetite quart-zites from upper to lower layers. The cito-porphyry is partially in gradual contact with the quartz trachyte. Its Rb-Sr dating is 420 Ma.The two porphyry is chemically calcalkalic and higher in SiO 2,K 2O,and lower in FeO,MgO,CaO,contrasting to the volcanic rocks of Gongpoquan group. Compared with the MORB,the porphyry is richer in lithophile elements and poorer in transition elements. The trance elements distribution is approximately flat which has a little of abnormal Eu.These indicate that two porphyrys are end-members of island-arc magma series along Gongpoquan-Dongqiyishan island-arc because the Hazakstan plate subducts at the Mid-late Silurian to the Tarim-S(ino)K(orea) plate.

关 键 词：地球化学 含矿斑岩 海相 岛弧型斑岩 公婆泉铜矿 岩石化学 微量元素 

分 类 号：P588.13[天文地球—岩石学] P597[天文地球—地质学]