摘要
近年,在大兴安岭柴河地区开展1∶5万区调时发现了碎斑熔岩体.区内发育晚侏罗世满克头鄂博组(J3m)、玛尼吐组(J3mn)及白音高老组(J3b)火山岩,广泛分布在二十四道沟、敖尼尔-四道沟及柴河-固里河3个火山喷发盆地中.所发现的固里河、敖尼尔两个碎斑熔岩体,即是白音高老期火山活动晚期侵出的重要组成部分.固里河碎斑熔岩体呈一北东向延伸的椭圆形穹状岩体,可划分出内部相(似斑状)、过渡相(霏细质)和边缘相(玻质)3个相带,主要由流纹质碎斑熔岩构成;敖尼尔碎斑熔岩主体呈近东西向,平面上呈似蘑菇状,可划分出2～3个相带,其岩石类型基本同固里河碎斑熔岩体.它们的发现,对研究大兴安岭地区火山岩的形成、演化及指导找矿等具有重要意义.
The porphyroclastic lava in Chaihe, Daxinganling region was found in recent years during the 1：50000 regional geological survey. Late Jurassic volcanic rocks of Manketouebo, Manitu and Baiyingaolao formations are developed in the Ershisidaogou, Aonier-Sidaogou and Chaihe-Gulihe volcanic erupted basins. The Gulihe porphyroclastic lava body, occurring as an oval dome extending in northeast direction, can be divided into internal facies （porphyritic）, transitional facies （felsitic） and external facies （hyaline）. The porphyroclastic lava in Aonier, trending in east-west, can be recognized in two or three facies. The lava bodies are composed of mainly rhyolitic lava, formed in the late stage of Baiyingaolao volcanism. The discovery of the porphyroclastic lava is significantly important to the study of the forming and evolving of the volcanic rocks, as well as the prospecting in the region.
出处
《地质与资源》
CAS
2012年第1期35-41,共7页
Geology and Resources
基金
中国地质调查局基础地质调查成果集成与综合研究项目(编号1212011121134)资助
关键词
碎斑熔岩
晚侏罗世
大兴安岭中段
柴河地区
porphyroclastic lava
Late Jurassic
middle Daxiangling Mountains
Chaihe area
