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根据主量元素、微量元素和Sr-Nd同位素地球化学研究结果,觉罗塔格构造带中企鹅山群火山岩企鹅山群火山岩分为拉斑玄武岩和钙碱性玄武岩,拉斑玄武岩和钙碱性玄武岩均具有高铝、低钛和相对富集轻稀土元素(LREE)、大离子亲石元素的特征,与典型的岛弧玄武岩相似。钙碱性玄武岩具有显著的Eu的负异常,其不相容元素含量显著高于拉斑玄武岩,在La/Sm-La图解中,钙碱性玄武岩为结晶分异作用的产物,拉斑玄武岩则为平衡部分熔融的产物。Sr-Nd同位素特征表明企鹅山群火山岩源自亏损地幔。在玄武岩构造环境判别图中样品均落入岛弧玄武岩范围内。通过综合该区岩石组合特征、地球化学特征、地球物理特征,认为企鹅山群为康古尔洋壳向北俯冲在大南湖岛弧南侧形成的石炭纪岛弧火山岩。
Based on the results of major elements, trace elements and Sr-Nd isotope geochemistry, the volcanic rocks in Penguishan Group, Penguashan Group, in the Jueluotag tectonic belt are divided into tholeiitic basalts and calc-alkaline basalts, tholeiitic basalts and calc-alkaline Basalts are characterized by high-aluminum, low-titanium, and relatively enriched LREEs and LILEs, similar to typical island-arc basalts. The calcareous basalts have significant negative anomalies of Eu and their incompatible elements contents are significantly higher than that of tholeiite basalts. The calcareous basalts are the product of crystallization differentiation in La / Sm-La diagram, while the tholeiite basalt To balance the partial melting of the product. Sr-Nd isotopic characteristics indicate that the Penguin Group volcanic rocks originated from depleted mantle. In the basalt tectonic setting, the samples all fall into the range of island arc basalt. Based on the characteristics of the rock assemblages, geochemical characteristics and geophysical characteristics in this area, Penguin Mountain Group is thought to be the Carboniferous island arc volcanic rocks formed on the south side of the Da Nanhu Island arc by the Kanggur oceanic crust northward.