摘要
木孜塔格地区蛇绿岩位于华北板块与华南板块所夹的昆仑结合带中.通过1∶25万区域地质调查,发现结合带中分布着畅流沟中元古代Sm-Nd等时线年龄为(950±82) Ma/(1 138±42) Ma及含二叠纪放射虫Pseudoalbaillella的蛇绿岩,反映了不同时期古洋壳的存在.其中,畅流沟蛇绿岩中的变质橄榄岩、超镁铁堆积岩为富集的大洋岩石圈地幔残迹;镁铁岩部分具P-MORB性质,部分具有岛弧的性质,表明其形成于过渡型洋脊环境.
The ophiolite of Changliugou of muzitage lies in Kunlun suture belt between North China plate and south China plate .By 1∶250000 regional geological survey ,middle proterozoic ophiolite was found Sm-Nd isochron method :its age is (950±82) Ma/(1138±42) Ma) and stretched uncontinually in the suture belt. These indicated the existence of old oceanic crust. Metamorphic peridotite and ultramafic cumulate in the basic-ultrabasic rock was the relicts of abundant oceanic lithosphere mantle. Some of mafic rock have P-MORB features, others have arc features. All these showed the basic-ultrabasic rock of Changliugou formed in the surrounding of interoceanic ridge.
出处
《新疆地质》
CAS
CSCD
2003年第3期263-268,共6页
Xinjiang Geology