| 西藏阿里地区火山岩的岩石系列及特征 |
| |
| 引用本文： | 路凤香
,赵崇贺.西藏阿里地区火山岩的岩石系列及特征[J].地球科学,1987(3). |
| |
| 作者姓名： | 路凤香 赵崇贺 |
| |
| 作者单位： | Wuhan College of Geology，Wuhan 430074 |
| |
| 摘 要： | 西藏阿里地区冈底斯构造带分布有早白垩世的玄武岩-安山岩-英安岩系列及晚白垩—第三纪的玄武岩-安山岩-流纹岩系列,它们分别属于拉斑玄武及钙碱性系列。前者主要由地幔导源的玄武岩浆经分离结晶作用形成,而钙碱性系列主要由混合作用及同化作用形成。此外其岩浆房的fO_2与fH_2O高,液相线温度偏低并与地壳导源的岩基活动有密切的关系.
|
| 关 键 词： | 拉斑玄武系列 钙碱性系列 分离结晶作用 混合作用 |
SERIES AND CHARACTERISTICS OF VOLCANIC SUITE IN ALI, XIZANG ( TIBET ) |
| |
| Lu Fengxiang Zhao Chonghe.SERIES AND CHARACTERISTICS OF VOLCANIC SUITE IN ALI, XIZANG ( TIBET )[J].Earth Science-Journal of China University of Geosciences,1987(3). |
| |
| Authors: | Lu Fengxiang Zhao Chonghe |
| |
| Abstract: | The earliest volcanic suite in Kalakunlun zone, Ali, Tibet is tholeiitic-alkali basalts in character, and it is formed under a relatively stable environment in Permo-Triassic. The second volcanic suite(k1)consists of basaltic lava and a few intermediate-acidic lava. These rocks are accompanied with serpentine peridotites, clastic sedimentary rock and radiolarites. This suite belongs to tholeiite series (TH).The evolution of TH series was mainly controlled by crystal fractionation involving olivine, pyroxene and no many iron-ores. The third volcanic suite (K22-E)which belongs to calc-alkali series (CA) is characterized by a thick (4500m) and good sequence of intermediate-acidic lava, pyroclastic rocks and a few sedimentary rocks. Magma mixing and assimilation are more important petrogenetic processes in CA series. It seems quite possible that the processes of magma in CA were more complicated than that in TH and the fo2 and fH2O estimated in basalts of CA were higher than that in basalts in TH. |
| |
| Keywords: | tholeiite series calc-alkali series crystal fractionation mixing |
| 本文献已被 CNKI 等数据库收录！ |
