公婆泉铜矿岛弧型含矿斑岩地质地球化学特征

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500－1000m,是中一晚志留纪哈萨克斯坦板块向（南）塔里木－中朝板块俯促时公婆泉－东七一山岛弧岩浆晚期分异的产物。

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

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.