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野外地质调查发现在阿尔泰南缘额尔齐斯构造带东段、额尔齐斯活动断裂与富蕴-锡泊渡断裂之间发育了一套未变形的酸性岩墙群。岩墙群侵位于海西期片麻岩化花岗岩和上石炭统深变质的额尔齐斯组岩层中,薄片鉴定和岩石地球化学分析确定为具有细晶结构的流纹斑岩。岩石的SiO_2含量为70.9%～75.38%,K_2O+Na_2O含量为7.55%～8.99%;大部分样品Na_2O>K_2O,里特曼指数值为1.8～2.5之间,Al_2O_3=12.80%～14.53%,A/CNK=0.9～1.1,NK/A=0.7～0.9,具有准铝质—弱过铝质、低镁、高钾钠、低钙和锶、高(Fe)_(mol)/(Mg)_(mol)特点,具A型花岗岩类特点,属于亚碱性脉岩。岩石轻稀土富集,大离子亲石元素相对富集,具有明显的中等负铕异常,壳源特征明显。锆石U-Pb二次粒子微探针测年显示岩墙群形成于277～286Ma。推断岩墙是阿尔泰海西期造山运动结束后,在拉张构造环境下的地壳局部熔融产物。
Field geological survey found that in the eastern margin of the Altay, the eastern part of the Qiqi Si tectonic zone, an undeformed acidic dyke swarm was developed between the Erqisi active fault and the Fuyun-Xipudu fault. The dyke swarms are located in the Hercynian gneissic granite and the Late Carboniferous metamorphic Irtysh group. The identification and lithogeochemical analysis of the dikes indicate the fine-grained rhyolite porphyry. The SiO_2 content of rock is 70.9% -75.38%, K_2O + Na_2O content is 7.55% ~ 8.99%, the Na_2O> K_2O of most samples is between 1.8 ~ 2.5 and Al 2 O 3 is 12.80% ~ 14.53% /CNK=0.9~1.1,NK/A=0.7~0.9, with quasi-aluminum - weak permalloy, low magnesium, high potassium sodium, low calcium and strontium, high (Fe) _ (mol) / (mol) characteristics, with A-type granite class, belonging to sub-alkaline veins. The rocks are enriched in light rare earths and relatively enriched in large ion-lithophile elements, with obvious moderate negative-negative Eu anomalies and obvious features of crustal sources. Zircon U-Pb secondary particle microprobe measurements showed that the dikes formed in 277 ~ 286Ma. It is inferred that the dyke wall is the crustal local melting product under the tensioned tectonic setting after the end of the Altay Hercynian orogeny.