全球大陆裂谷玄武岩数据挖掘的初步结果  

Preliminary Results of Data Mining of Global Continental Rift Basalts

作　　者：李玉琼 杜雪亮 马蓁 王金荣 

机构地区：[1]兰州大学地质科学与矿产资源学院甘肃省西部矿产资源重点实验室(兰州大学),兰州730000

出　　处：《矿物岩石地球化学通报》2017年第6期912-919,共8页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：中央高校基本科研业务费专项资金项目(lzujbky-2016-197)

摘　　要：大陆裂谷是大陆内部的拉张地带,与地幔软流圈的隆升有关。大规模玄武岩浆侵位是大陆裂谷发展的重要特征。新生代大陆裂谷玄武岩(CRB)的时空分布表明,CRB绝大部分出现在更新世,暗示更新世可能是全球拉张最明显的时期。大数据研究表明,CRB与洋岛玄武岩(OIB)、大陆溢流玄武岩(CFB)的地球化学特征虽然存在一些差别,但总体上类似。与CFB和OIB相比,CRB的LILE和LREE更加富集,可能与岩浆混染程度较高及部分熔融程度较低有关。与OIB相比,虽然它们都是深源的,但是,CRB的源区深度可能略浅一些,而混染程度略高一些。The continental rift, which is the tension zone of intra-continent, is related to the uplift of mantle astheno- sphere. Large-scale basaltic magmatic emplacement is an important feature of the continental rift development. The spatial and temporal distribution of the Cenozoic continental rift basalt （CRB） shows that most Cenozoic CRBs occur in Pleisto- cene, suggesting that it could be the predominant period of global tension in Cenozoic. Big data research shows that the CRB, oceanic island basalt （OIB） and continental flood basalt （CFB） have generally similar geochemical characteristics with a few exceptions. Comparing to the CFB and OIB, the CRB has relative enriched LILE and LREE. This could be re- lated to the magma was formed by relative high degree magmatic contamination and low degree partial melting. Comparing to the OIB, which was derived from deep source, the CRB could be formed in slightly shallower depth by the slightly high- er degree contamination.

关 键 词：大陆裂谷玄武岩 大陆溢流玄武岩 洋岛玄武岩 大数据 源区 混染作用 

分 类 号：P588.145[天文地球—岩石学]