大兴安岭北端塔木兰沟组玄武质岩石的地球化学特征及构造背景

中国地质大学地球与资源学院，中国地质大学地球与资源学院，中国地质大学地球与资源学院，黑龙江省地质调查研究总院齐齐哈尔分院北京100083 黑龙江省地质调查研究总院齐齐哈尔分院，黑龙江齐齐哈尔161005，北京100083 黑龙江省地质调查研究总院齐齐哈尔分院，黑龙江齐齐哈尔161005，北京100083 黑龙江省地质调查研究总院齐齐哈尔分院，黑龙江齐齐哈尔161005，黑龙江齐齐哈尔161005

基金项目: 中国地质调查局国土资源调查项目(0100123059)资助

Geochemical characteristics and tectonic setting of basaltic rocks of the Tamulangou Formation at the northern end of the Da Hinggan Mountains, China

School of Earth Science and Mineral Resources,China University of Geosciences,Beijing 100083,China,2. Qiqihar Branch,Heilongjiang Institute of Geological Survey,Qiqihar 161005,Heilongjiang,China

摘要: 大兴安岭北部晚侏罗世塔木兰沟组玄武质岩石具有富碱(K2O+Na2O>5.45%),高K2O(2.15%～3.75%)、K2O/Na2O(0.48～1.12)和高的Th/Ta、Ce/Nb、Ta/Nb比值,以及强烈富集大离子亲石元素(LILE)和轻稀土元素(LREE)的特征,属于钾玄质系列。现有资料分析表明,该钾玄质岩石形成于大陆板内环境。元素地球化学特征揭示,形成钾玄质岩石的原生岩浆经过强烈的结晶分异作用,并混染了前中生代的基底物质。
- 钾玄质岩石 /
- 地球化学 /
- 晚侏罗世 /
- 大陆板内 /
- 大兴安岭北部
Abstract: Basaltic rocks of the Late Jurassic Tamulangou Formation in the northern Da Hinggan Mountains are characterized by rich alkalis (K2O+Na2O>5.45%),high K2O (2.15%- 3.75%),high ratios of K2O /Na2O (0.48- 1.12),Th /Ta,Ce/Nb and Ta/Nb and strong enrichment in large- ion lithophile elements (LILE)and light rare earth elements (LREE),belonging to the shoshonitic series. Analysis of the available data indicates that these shoshonitic rocks formed in a continental intraplate set- ting. Geochemical characteristics suggest that the primary magma of these shoshonitic rocks underwent strong crystallization dif- ferentiation and was contaminated with pre- Mesozoic basement materials.
- shoshonite /
- geochemistry /
- Late Jurassic /
- continental intraplate setting /
- northern Da Hinggan Mountains