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西藏羌塘地区火山岩主要见于第三系石坪顶组，主要岩石类型是呈熔岩被产出的火山熔岩，包括辉石粗安岩、角闪粗面岩、角闪英安岩、黑云母英安岩等，其次可见次火山岩相的黑云母英安质碎斑熔岩和黑云母粗面质碎斑熔岩，以及辉石黑云母花斑岩．它们均为陆相中心式喷发的产物．岩石化学上属钾玄岩组合，可进一步分为钾玄岩系列和高硅钾玄岩系列，具非常典型的二元岩浆混合成因火山岩的岩石化学特征．其ＲＥＥ及微量元素特点表明二元岩浆混合前两个端元岩浆分别来自幔源和壳源．这些火山岩岩浆热事件对盆地有机烃类转化为石油和天然气是有利的，而破坏作用仅仅发生在火山机构附近
The volcanic rocks in the Qiangtang area of Tibet are mainly found in the Shibeiping Formation of Tertiary. The main types of rocks are volcanic lava that is produced by lava, including pyroxene, amphibolite, amphibole, biotite Anan, etc. Secondly, the biotite amphibolite-hosted amphibolite lava and biotite coarse-grained crustal lava and pyroxene micaceous porphyry are observed. They are all products of continental facies eruptions. The petrochemistry is a combination of Potashites, which can be further divided into a series of Potashites and a series of high-K-type potashites, with typical petrochemical characteristics of volcanic rocks of mixed binary magmatic origin. The REE and trace element characteristics show that the first two terminal magmatic fluids from the magma are derived from the mantle source and the crust source, respectively. These volcanic magmatism events are favorable for the conversion of organic hydrocarbons from the basin to oil and gas, with destructive effects occurring only in the vicinity of volcanic institutions