可可西里北缘中新世火山活动带的基本特征

可可西里北缘火山活动带为可可西里中新世火山活动区数条火山活动带之一,其特征十分典型。本文以火山地质、同位素、岩石化学以及稀土元素地球化学为基础对其岩浆来源、演化、火山活动规律进行了研究。该火山带粗安岩-粗面岩-亚碱性流纹岩组合与世界高原溢流玄武岩类似,同时反映大陆伸展的构造环境。

FUNDAMENTAL CHARACTERISTICS OF MIOCENE VOLCANIC ACTIVE BELT IN THE NORTHERN MARGIN OF HOH XIL

As one of several belts of Miocene volcanic active area of Hoh Xil,the volcanic belt islocated in the northern margin of Hoh Xil,and has its typical characteristics.In terms of volcanic geology,isotope,petrochemistry,and REE geochemistry,the magmatic sourceand evolution,the volcanic active regularity have been discussed in this paper.The association of trachyandesite-trachyte-subalkaliliparite is similar to the plateau effusion basaltdeveloping over the world,and reflects a tecctoriic pattern of the continental expansion.