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北祁连造山带中存在“南方型”和“北方型”构造基底岩块。“南方型”构造基底岩块和柴达木古陆相似 ,“北方型”构造基底岩块则和华北古陆相似。两种不同的构造基底岩块随着祁连洋的消失而相遇于北祁连造山带 (缝合带 )中。在祁连洋的俯冲过程中 ,形成了不同的成矿系统 ,与“北方型”构造基底岩块有关的成矿系统为加里东期活动大陆边缘成矿系统———白银、清水沟铜及多金属成矿组合 ;与“南方型”构造基底岩块有关的成矿系统为中、新元古代活动大陆边缘弧后裂解成矿系统———镜铁山—柳沟峡铁成矿组合 ,加里东期活动大陆边缘与俯冲作用有关的成矿系统———岩浆热液钨成矿组合及铅锌成矿组合。两种构造基底岩块的确认 ,可为北祁连缝合带的成矿系统的建立及找矿工作 ,提供新的思路 ,也为北祁连造山带性质的认定 ,提供成矿作用信息方面的限制。
In the North Qilian orogen, there are “southern” and “northern” tectonic basement rocks. The “southern type” tectonic basement rock is similar to the Qaidam ancient continent. The “northern type” tectonic base rock mass is similar to the ancient North China. Two different tectonic basement rocks met the North Qilian orogenic belt (suture zone) with the disappearance of the Qilian ocean. During the subduction of the Qilian Ocean, different metallogenic systems have been formed. The metallogenic systems related to the “North-type” structural basement rock are the continental margin metallogenic systems of the Caledonian continental margin --- Baiyin, Qingshuigou copper and polymetallic Metallogenic assemblages. The ore-forming system related to the “southern” basement rock is the mid-and late Neoproterozoic continental margin post-arc cleavage metallogenic system-the Jingtishan-Liuligou iron ore-forming assemblage, the Caledonian Period-related continental margin and subduction-related metallogenic systems --- magmatic hydrothermal tungsten mineralization and lead-zinc mineralization. The confirmation of two kinds of tectonic base rock blocks may provide a new idea for the establishment of the metallogenic system and ore prospecting of the North Qilian suture zone and also provide information for identifying the nature of the North Qilian orogenic belt and providing information on the mineralization limit.