【摘要】 康马岩体位于西藏南部康马县城北侧 ,其内部可划分出 5种不同的岩石类型 :(1)片麻状黑云二长花岗岩 ;(2 )眼球状黑云二长花岗岩 ;(3)片麻状二云母二长花岗岩 ;(4 )弱片麻状细粒黑云二长花岗岩 ;(5 )变质的暗色辉长辉绿岩。前两类为康马岩体的主体岩石类型 ,侵位时代为加里东早期 (约4 78～ 4 6 1Ma) ;其余均呈脉状产出 ,其中片麻状二云母二长花岗岩与康马岩体主体岩石类型属于同期产物 ,弱片麻状细粒黑云二长花岗岩形成于海西早期 ((339.0± 1.2 )Ma) ,暗色辉长辉绿岩的形成时代目前还不十分清楚。不同类型的岩石其Ar Ar冷却年龄约为 18～ 14Ma。更多还原

【Abstract】 The Kangmar gneissic dome is located in the north of Kangmar County, southern Tibet, including five different rock types as follows: (1) gneissic biotite adamellite; (2) augen gneissic biotite adamellite; (3) gneissic di-micaceous adamellite; (4) weakly-gneissic fine-grained biotite adamellite; and (5) dark-colored diabase (diabase-porphyrite) which was metamorphosed and deformed to amphibotite. The former two, whose emplacement age is the early Caledonian epoch (461～478 Ma), are the major rock types of the Kangmar gneissic dome; the others are developed as veins, among which gneissic dimicaceous adamellite is as old as the major rock type of the Kangmar gneissic dome, and weakly-gneissic fine-grained biotite adamellite is formed in the early Hercynian ((339.0±1.2) Ma), and the formation age of dark-colored diabase (diabase-porphyrite) is not clear.更多还原