辽河群含硼岩系基性火山岩地球化学特征及形成环境  

Geochemical characteristics and forming environment of boron-bearing rock series base volcano rock in Liaohe Group

作　　者：杨玉伟 余超 YANG yu-wei YU chao(Liaoning material testing exploration institute, Shenyang 110121, Liaoning, China Liaoning Institute of Geology and Mineral Resources Survey, Shenyang 110031, Liaoning, China)

机构地区：[1]辽宁省物测勘查院,辽宁沈阳110121 [2]辽宁省地质矿产调查院,辽宁沈阳110031

出　　处：《吉林地质》2016年第3期44-47,共4页Jilin Geology

摘　　要：以往研究认为辽东古元古界地层中存在基性火山岩和中酸性火山岩组成的双峰式火山岩,并以此作为辽吉大陆裂谷的重要证据。本文重点讨论了辽河群含硼岩系中基性火山岩的地球化学特征,结果表明,这些基性火山岩原岩为玄武岩,属高钾—中钾玄武岩,具有拉斑玄武岩和碱性玄武岩双重特征。主量元素表现为富钠、低硅、高铁的特征。稀土元素配分曲线主要显示平坦型曲线,与大洋环境下形成的正角闪岩具有较为相似的稀土元素分布模式。辽河群含硼岩系中基性火山岩原岩的形成环境为大洋环境。The previous studies indicate that Paleoproterozoic Erathem formation in eastern Liaoning Province has bimodal volcanic rocks, which is composed of basic volcanic rock and intermediate-acid volcanic, and as an important proof for Liaoning-Jilin continental rift. This article mainly discusses the geochemical characteristics of intermediatebasic volcanic rocks in boron-bearing rock Series of Liaohe Group. The result shows that the protolith of this intermediatebasic volcanic rocks are basalts, which belong to high-K or medium-K basalts and have the double characteristics of tholeiite and alkali basalt. The major elements has characteristic of rich K, poor Si and high Fe. REE distribution patterns are mainly flat types which is similar with oceanic orthoamphibolite＇s. The intermediate-basic volcanic rocks in boronbearing rock series of Liaohe Group formed in oceanic environment.

关 键 词：辽河群 玄武岩 地球化学特征 大洋环境 

分 类 号：P588.14[天文地球—岩石学]