新疆西天山艾肯达坂组火山岩的地球化学特征

THE GEOCHEMICAL CHARACTERISTICE OF AIKENDABAN GROUP VOLCANIC ROCKS IN WEST TIANSHAN MOUNTAINS,XINJIANG

新疆西天山艾肯达坂组火山岩的岩石学和稀土元素的地球化学等研究证明,本区火山岩由基性火山岩和中性火山岩组成,火山岩均属于钙碱性系列,二者均具有低钾、富钠的特点。这些火山岩的稀土元素配分曲线均属于轻稀土富集型,明显地表现为轻稀土元素配分曲线陡倾,而重稀土元素配分曲线相对平坦的特征。这些岩石学和地球化学的特征证明本区火山岩形成于裂谷环境。

Abstract：It is suggested basic lava and intermediate lava constitute the volcanic rolcanic by the lithology and the testing of rare earth element in west Tianshan Mountains. They are all belong to calcic-alkalic series. Both of them have lower potassium and high sodium. The REE distribution patterns of the volcano indicate that they have a rich light REE. The curve is steep in light REE while relatively flat in heavy REE. All these characteristics reflect that the volcano was formed in the rift-valley environment.