炭窑口矿区基性火山岩地球化学特征及其构造意义  

Geochemical Characteristics of Metamorphic Basic Volcanic Rocks of the Tanyaokou Ore District,Inner Mongolia and Its Tectonic Significance

作　　者：陈喜峰[1] 

机构地区：[1]中国冶金地质总局矿产资源研究院,北京100025

出　　处：《地质与勘探》2010年第1期113-119,共7页Geology and Exploration

基　　金：国家科技支撑计划课题(编号:2006BAB01A09)资助

摘　　要：为探讨炭窑口矿区变质基性火山岩的地球化学特征及其构造意义,对其产出特征、岩石学、岩石化学、地球化学等方面进行了综合分析研究。结果表明,其原岩为钾质细碧岩,属碱性火山岩,富集轻稀土和不相容元素,而亏损重稀土和相容元素(如Nb、Ta和Ti),具有与火山弧基性火山岩相似的地球化学特征。其稀土元素分配型式表明其成岩物质来源于地幔。通过构造环境分析,并结合区域地质资料,认为矿区变质基性火山岩的形成构造环境为大陆边缘火山弧造山带。In order to investigate the geochemical characteristics of metamorphic basic volcanic rocks of Tanyaokou ore district and its tectonic signifi- cance, the occurrence characteristics, petrology, petrochemistry and geochemistry characteristics of metamorphic volcanic rocks are studied. The results show that the primary part of metamorphic basic volcanic rocks is potassic spilite. Geochemical analyses demonstrate that metamorphic basic volcanic rocks are strongly enriched in LREE and incompatible elements and depleted in HREE and other compatible elements,such as Nb,Ta and Ti ,and have the similar geo- chemical characteristics with the volcanic arc basic volcanic rocks. The model of rare earth element （REE） of the basic volcanic rocks shows that its rock- forming elements came from mantle. Based on the research of rock-forming environment and the regional geological researches, it can be confirmed that the metamorphic basic volcanic rocks of Tanyaokou ore district is formed in continental marginal volcanic arc orogenic belt environment.

关 键 词：基性火山岩 地球化学 火山弧造山带炭窑口内蒙古 

分 类 号：P595[天文地球—地球化学]