东天山尾亚复式岩株形成时代讨论  

AGE OF FORMATION OF WEIYA COMPOSITE STOCKS IN EASTERN TIANSHAN MOUNTAINS

作　　者：李嵩龄[1] 李文铅[1] 冯新昌[1] 董富荣[1] 

机构地区：[1]新疆维吾尔自治区地质矿产勘查开发局第一区域地质调查大队,新疆乌鲁木齐830011

出　　处：《新疆地质》2002年第4期357-359,共3页Xinjiang Geology

摘　　要：尾亚复式岩株由尾亚超单元(外环)及环形山超单元(内环)组成。由完全不同成分、不同岩浆源的两个独立岩浆作用,沿同一通道就位的产物。外环为碱性辉长岩、石英正长岩、碱长花岗岩,内环为钙碱系列的石英闪长岩-花岗闪长岩-二长花岗岩-钾长花岗岩。北侧侵入于早石炭世卡拉火大山组及白尖山超单元中。依据同位素年龄测定,其生成年龄270.67～267.3Ma,为早二叠世;环形山超单元生成年龄230～250Ma,为晚二叠世。Weiya composite stocks comprise a circular body including Weiya super-unit (outer circle) and Huanxinshan super-unit (inner circle). It is a product of two phases of magmatic intrusion with different composition and magmatic source along the same intrusive passage. The outer circle consists of alkaline gabbro, quartz syenite and alkali-feldspar granite. The inner circle consists of quartz diorite-granodiorite-adamellite-moyite of calc-alkaline series. The stocks intruded into mylonitized Karahodashan Formation with early Carboniferous fossils and Baijianshan super-unit. The isotopic dating gives an age of 270.67-267.3 Ma for Weiya super-unit, and 230-250 Ma for Huanxinshan super-unit. Therefore the age of formation of Weiya composite stocks is constrained as Permian.

关 键 词：形成时代 复式岩株 同位素年龄 晚二叠世 岩浆 

分 类 号：P597[天文地球—地球化学]