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藏北唐古拉坳陷中央隆起带与北部凹陷带海相体罗－白垩纪地层中，夹杂一套以高钾安山岩、高铝玄武岩为主体的高钾钙碱性火山岩系列。主要岩石类型有玄武岩、高铝玄武岩、高钾安山岩、英安岩、流纹岩及流纹质角砾凝灰岩。根据火山岩产出特征和全岩同位素年龄测定，将本区火山活动划分为中生代晚期和老第三纪两个旋回。这套火山岩系的REE、相容元素和不相容元素分布特点与造山带火山岩类似；在构造判别图解上，其投影点均落在造山带大山岩区域内。对火山岩特征分析表明，它们的形成与俯冲作用有关，显示出在俯冲造山带的构造背景下演变而来。
In the central uplift belt of the Tangula depression in the northern Tibet and the marine syncro-Cretaceous strata in the north depression zone, a series of high-K calc-alkaline volcanic rocks are mainly composed of high-K andesite and high-Al basalt. The main rock types are basalt, high-alumina basalt, high-potassium andesite, dacite, rhyolite and rhyolitic breccia tuff. Based on the volcanic output characteristics and the isotopic dating of the whole rock, the volcanic activity in this area is divided into two cycles of Late Mesozoic and Oligocene. The REE, compatible elements and incompatible elements in this volcanic series are similar in distribution to volcanic rocks in the orogenic belt. On the tectonic discrimination diagram, the projection points of the REE, volcanic rocks and the volcanic rocks fall within the orogenic rock zone. Analysis of the volcanic rocks shows that their formation is related to subduction and evolves from the tectonic setting of the subducted orogenic belt.