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安家营子金矿位于华北克拉通北缘金矿成矿带的中部,其北紧邻兴蒙造山带.华北陆块与兴蒙造山带之间的边界断裂即赤峰-开原断裂从附近经过,是区域性控矿断裂.安家营子金矿为一中型矿床,矿体主要赋存于安家营子花岗岩体中.与金矿化相伴生广泛分布着流纹斑岩、煌斑岩等岩脉.对安家营子花岗岩、穿切矿体的流纹斑岩岩脉的锆石U-Pb年龄测定表明,安家营子花岗岩的侵位时代为132～138 Ma,流纹斑岩的成岩时代为124.9～126.5 Ma.根据矿体与花岗岩、脉岩之间的穿切关系将安家营子金矿成矿时代限定在126～132 Ma,即早白垩世.这一年龄与华北克拉通上其他主要金矿集中区的成矿年龄是一致的,也与华北克拉通中生代动力学体制发生转折的时间相吻合.这表明华北克拉通上绝大多数金矿床,包括安家营子金矿床形成的动力学背景是相同或相似的,即形成于中生代大规模的岩石圈减薄的构造背景下.
The Anjialingzi gold deposit is located in the middle of the gold ore belt on the northern margin of North China Craton and to the north of the Xingmeng orogenic belt.The boundary fault between the North China block and the Xingmeng orogenic belt is the Chifeng-Kaiyuan fault passing nearby, Is a regional ore-control fault.Anjiayingzi gold deposit is a medium-sized deposit, the ore body mainly occurs in the granite body of the Anyjiayingzi granite.The rhyolitic porphyry and lamprophyre dykes are widely distributed along with the gold mineralization The zircon U-Pb dating of the rhyolite porphyry dike from the Anyijiayingzi granite shows that the emplacement age of the Anyjiayingzi granite is 132 ~ 138 Ma, and that of the rhyolite porphyry is 124.9 ~ 126.5 Ma.According to the relationship between orebodies and granites and veins, the mineralization age of the Anyijiayingzi gold deposit is limited to 126-132 Ma, ie, the Early Cretaceous.The age is similar to that of the other major The ore-forming age of gold deposits is consistent with the timing of the turning of Mesozoic karst craton in North China, indicating that the dynamics of the formation of most of the gold deposits in the North China Craton, including the Anjiayingzi gold deposit The background is the same or similar, that is formed in the Mesozoic large-scale Rock circle thinning on the tectonic background.