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该成矿带位于北祁连加里东优地槽的东南缘。这里是向南俯冲敛合板块残留的岛弧。根据大地构造环境,伴生的岩石类型,矿床沉积时间短、地层狭窄,受两组相交断裂控制的火山机构制约,蚀变带比较完整,矿体形态、规模、产状、矿石物质成分、矿石结构构造、矿石类型、分带特征,硫同位素组成,矿物包裹体特征、成分、温度,矿床与围岩年龄等,本矿区均可与日本黑矿对比。矿石与围岩变质程度接近,含矿层上部层位见有火山矿石角砾,矿体和不纯大理岩接触见不到交代现象,小铁山矿体上部无化探异常,以及稀土元素地球化学特征等,为该类矿床提供了新的依据。块状矿体应是海底火山—喷气沉积成因,围绕块状矿体的细脉浸染状矿体,应属变质层控矿床。
The metallogenic belt is located in the southeastern margin of the Caledonian Trough in North Qilian. Here is the subduction of convergence plate convergence south island arc. According to the tectonic setting of the tectonic environment, associated rock types, short deposition time and stratigraphic strata, it is restricted by volcanic structures controlled by two intersecting faults. The alteration zone is relatively complete. The ore body morphology, scale, occurrence, ore composition and ore structure Structure, ore type, zoning characteristics, sulfur isotopic composition, mineral inclusion characteristics, composition, temperature, ore and rock age, the mine area can be compared with the Japanese black ore. The degree of metamorphism of the ore and the surrounding rock is close to that of volcanic ore breccia in the upper strata of the ore-bearing layer. No contact occurs between the ore body and the impure marble, there is no geochemical anomaly in the upper part of the Xiaotieshan ore body, and rare earth element geochemistry Features, etc., provide a new basis for this type of deposit. Massive orebodies should be the origin of submarine volcano-jet deposition. The veinlets disseminated around massive orebodies should belong to the metamorphic stratabound ore deposit.