石油与天然气地质 ›› 1997, Vol. 18 ›› Issue (4): 314-318.doi: 10.11743/ogg19970410

• 论文 • 上一篇    下一篇

新疆三塘湖早石炭世玄武岩地球化学特征及构造环境意义

龚文平, 林克湘, 李艺斌   

  1. 江汉石油学院 湖北荆州 434102
  • 收稿日期:1996-10-28 修回日期:1997-04-11 出版日期:1997-12-25 发布日期:2012-01-18

GEOCHEMICAL CHARACTERISTICS OF EARLY CARBONIFEROUS BASALTS IN SANTANGHU REGION,XINGJIANG AND THEIR SIGNIFICANCE IN TECTONIC SETTINGS

Gong Wenping, Lin Kexiang, Li Yibin   

  1. Jianghan Petroleum Institute, Jingzhou, Hubei
  • Received:1996-10-28 Revised:1997-04-11 Online:1997-12-25 Published:2012-01-18

摘要:

三塘湖地区早石炭世火山活动强烈,发育以安山岩类为主的玄武岩、安山岩、英安流纹岩的岩石组合。玄武岩类具有Al2O3含量高,铁含量低,TiO2含量低,大离子亲石元素及轻稀土元素富集的钙碱性系列特点。微量元素比值蛛网图和稀土元素配分型式具有岛弧钙碱性玄武岩的特征。利用不同构造环境玄武岩的Nb-Zr-Y图式、Cr-Ce/Y图式判别出三塘湖地区在早石炭世为岛弧构造环境。

关键词: 玄武岩, 微量元素, 地球化学, 岛弧, 早石炭世, 三塘湖, 新疆

Abstract:

Volcanicity was violent during the Early Carboniferous in Santanghu region.The volcanic rocks consist of basalts,andesites and dacite liparite,with andesites playing the main part.Geochemical analysis indicates that the basalts are characterized by high content of Al2O3,low contents of FeO+0.9Fe2O3 and TiO2,rich macroion lithophile element(LIL)and LREE.The spider diagram of trace element ratio and the REE distribution patterns show the characteristics of the island arc calc alkaline series.In addition,basalt discrimination diagrams,such as Nb-Zr-Y and Cr-Ce/Sr,suggest that Santanghu area was in an island arc envirnment during the Early Carboniferous.