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克兰河中游英云闪长岩和二长花岗岩的锆石LA-ICP-MSU-Pb年龄分别为400±2.3Ma(MSDW=1.1)和401±3.3Ma(MSDW=1.2),表明岩体侵位于早泥盆世早期,同时也暗示了岩体围岩康布铁堡组地层的形成时代早于401Ma。所有花岗质岩石具有高的SiO2(67.80%~76.54%)和Al2O3(12.39%~16.07%)含量,低P2O5(0.02%~0.17%)和MgO+FeO(2.22%~5.12%)含量,富碱(K2O+Na2O=5.58%~8.25%),具有低的CaO/Na2O(<0.3)比值和高的A/CNK值(0.96~1.39);富集LREE和Th、U,贫Ba、P、Sr、Ti、Nb,呈现明显的Eu负异常(δEu=0.22~0.73)。以上特征表明该岩体属钙碱性准铝质-过铝质岩类,具有岛弧花岗岩的典型特征。结合阿尔泰南缘的区域地质背景综合分析,推测岩体形成于活动大陆边缘环境,是在俯冲作用过程中由变泥质岩和变质杂砂岩脱水熔融的产物,在部分熔融过程中有磷灰石、斜长石、钛铁矿等矿物的残留。
The zircon LA-ICP-MSU-Pb ages of the Yingke and Changlong granites in the middle reaches of the Krane River are respectively 400 ± 2.3Ma (MSDW = 1.1) and 401 ± 3.3Ma (MSDW = 1.2) Located in the early Devonian, it also implied that the formation age of the Kangbubu Formation in the rock mass was earlier than 401 Ma. All granitic rocks have high content of SiO2 (67.80% ~ 76.54%) and Al2O3 (12.39% ~ 16.07%), low P2O5 content of 0.02% -0.17% and MgO + FeO content of 2.22% ~ 5.12% (K2O + Na2O = 5.58% ~ 8.25%) with low CaO / Na2O (<0.3) and high A / CNK values of 0.96 ~ 1.39; enrichment of LREE, Th, U, Sr, Ti and Nb show obvious Eu negative anomalies (δEu = 0.22-0.73). The above characteristics indicate that the rock body is a calc-alkaline quasi-aluminum-peridotite with the typical features of island arc granite. Based on the comprehensive analysis of the regional geological background in the southern margin of Altay, it is speculated that the rock mass is formed on the active continental margin and is the product of dewatering and melting of metamorphic and metamorphic sandy rock during the subduction. In part of the melting process, apatite , Plagioclase, ilmenite and other mineral residues.