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可可西里地区的新生代火山岩属于藏北火山岩带的东段。火山岩主要以熔岩台地、桌状山的形式产出，熔岩厚约４０—１００ｍ。除少量的高钾流纹岩、粗面岩和粗面英安岩外，在数量和分布上以普遍含二辉石斑晶的安粗岩占优势。岩石以富碱（尤其富钾）和富ＬＲＥＥ为特征。火山活动发生在中新世，根据Ｋ／Ａｒ定年结果划分为早、中、晚三期。本区火山岩的特征与西藏境内的同时代岩石完全可以对比。火山活动与高原新生代以来的岩石圈演化有密切的关系
The Cenozoic volcanic rocks in the Hoh Xil region belong to the eastern section of northern Tibet volcanic belt. Volcanic lava mainly in the mesa, table-shaped mountain output, lava thickness of about 40-100m. Except for a small amount of high-k rhyolite, mafic and mafic dacite, the abundance and abundance of dacitestone-bearing amphiboles predominate in quantity and distribution. Rocks are characterized by alkali-rich (especially potassium-rich) and LREE-rich. Volcanic activity occurred in the Miocene. According to the K / Ar dating results, it was divided into three phases: early, middle and late. The characteristics of volcanic rocks in this area can be completely contrasted with that of contemporaries in Tibet. Volcanic activity is closely related to the evolution of lithosphere since the Cenozoic