贵州麻江金云火山岩(钾镁煌斑岩)的地质特征  

Geology of the Lamproites in Majiang, Guizhou

作　　者：任怀翔 张光文 

机构地区：[1]贵州省地质矿产局101地质大队

出　　处：《贵州地质》1993年第3期189-191,共3页Guizhou Geology

摘　　要：1992年我队在麻江地区发现一批金云火山岩(钾镁煌斑岩)岩体,其中岩管5个。产出的大地构造部位在江南台隆与黔南坳陷的交接部位偏向坳陷一侧,围岩为下、中寒武统。岩石具斑状结构、交代结构、环边结构及块状构造。组成矿物有云母、橄榄石、辉石、铬铁矿、钛铁矿、锐钛矿、碳硅石、磷灰石、钙钛矿、刚玉、金红石、紫苏辉石、石榴石、锆石、独居石、电气石等。岩石化学分析显示偏碱性超基性特征,稀土元素含量特高。新发现岩石命名为橄榄金云火山岩及(过渡型)金云火山岩。其含金刚石性待定。40 lamproite bodies including five lamproite volcanic pipes were found in Majiang county of Guizhou provicne in 1992. These lamproites tectonically in the transition between the Jiangnan Uplift and the South Guizhou Depression occur in the the mid-upper Cambrian, these rocks display porphyritic, metasomatic and corona fextures and their structures are mainly massive. The minerals composed of the rocks are mica, olivine, pyroxene, chromite ,ilmenite ,anatase ,moissanite, apatite ,perovsckite ,corundum, rutile ,hypersthene, garnet, zircon, monazite, tourmaline and so on. Chemical analyses of the lamproites show these rocks are bias alkli to ultrabasic ones, named as olivine-lamproites with quite high content of REE. The study of the mineralization in this type of rocks is currently in progress.

关 键 词：火山岩 地质特征 钾镁煌斑岩 

分 类 号：P588.14[天文地球—岩石学]