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对觉罗塔格地区南缘的晚石炭世土古土布拉克组火山岩进行了岩相学、岩石地球化学研究。结果显示:该组以中酸性岩为主,岩石组合包括玄武岩、安山岩、英安岩和流纹岩,从基性到酸性有明显的演化趋势,具有富钾的高钙碱性特征。大部分岩石具有大离子元素和轻稀土元素富集,重稀土平坦,高场强元素相对亏损,富铝低钛的地球化学特征,属于典型的岛弧火山岩。其形成及成岩过程与北部古亚洲洋的演化有关,即该组火山岩是古亚洲南缘洋壳向南俯冲作用的产物。结合已有研究成果,认为觉罗塔格南缘在晚石炭世早期仍处于岛弧环境。
Phyolithotectonics and lithogeochemistry were studied on the volcanic rocks of the Late Carboniferous Turbula Group in the southern margin of Jueluotag area. The results show that the group is mainly composed of medium-acid rocks. The rock assemblages include basalts, andesites, dacite and rhyolite. They evolve evidently from base to acidity, and have the characteristics of high-calcium-rich alkaline potassium. Most of the rocks are characterized by large ion and light rare earth elements, flat heavy rare earth elements, relatively high depletion of high-field elements and geochemical characteristics of aluminum-rich and low-titanium rocks, which are typical of island arc volcanic rocks. Its formation and diagenesis are related to the evolution of the Paleo-Asian Ocean in the north, that is, the volcanic rocks of this group were the result of the southward subduction of the oceanic crust in the southern margin of the ancient Asia. Combined with the existing research results, it is concluded that the southern edge of Jueluotage is still in the arc environment in the early stage of Late Carboniferous.