摘要
海南岛北部广泛分布的新生代火山岩，严格受“雷琼坳陷带”边界的控制，其中碱性玄武岩系列的岩石，主要分布在坳陷带边部，形成于上第三纪；拉斑玄武岩系列的岩石，主要分布在坳陷带中心部位，形成于第四纪。玄武岩以富Ｋ，Ｐ，Ｒｂ，Ｚｒ，Ｓｒ，Ｂａ，Ｔｈ，Ｔａ，Ｎｂ，ＬＲＥＥ，贫Ｙ及Ｙ／Ｎｂ＜１为特征，显示板内大陆裂谷岩浆作用的特点。
Cenozoic volcanic rocks are widely distributed over northern Hannan Island and their distributing ranges are strictly confined in “Lei-Qiong depression Zone”, The studied region has rocks of alkalic and tholeiitic series. The former is distributed near the border of the depression zone and the forming age is older; the latter is distributed in the center position and the forming age is later. Basalts in this region are rich in K, P, Rb, Ba, Zr, Sr, Th, Ta, Nb, LREE and poor in Y and Y/Nb<1. Those wholely show characteristics of magmatism in the continental rift within plate.
出处
《桂林工学院学报》
1997年第1期26-33,共8页
Journal of Guilin University of Technology
关键词
玄武岩
火山作用
大陆裂谷
构造环境
火山岩
basalt
Cenozoic
volcanism
depression zone
continental rift
tectonic settings
Hannan Island
