豫西沙沟银铅锌矿床构造控矿分析及找矿预测

Analysis of ore-controlling structures and prospecting predicting of the Shagou Pb-Zn-Ag deposit in the western Henan Province

沙沟铅锌银矿床位于豫西有色金属重点成矿区,华北地台南缘与秦岭造山带相接带,出露的地层主要为新太古界太华岩群高级变质岩系,属于薄脉状构造蚀变岩型矿床,矿体严格受断裂构造控制。含矿构造破碎带以北北东向为主,其次为近南北向和近东西向。该矿床形成于晚侏罗世中国东部构造体制大转换初期。北西西—南东东向主压应力场迁就、利用、改造已经形成的近南北向主压应力场产生的断裂构造体系,原来的断裂构造的产状没有发生大的变化,但叠加了新的力学性质。文章认为该矿区找矿潜力很大,通过构造分析提出了下一步找矿的重点部位和方向。

The Shagou lead -zinc - silver deposit is located in the key metallogenic belt of non -ferrous metallic deposits in western Herman Province, occurred at the jointed section of the south China platform and Qinling orogenic belt. The outcropped host strata is the Archean high metamorphic rocks of Taihua group. The deposit is a thin vein structural - controlled altered type Pb - Zn - Ag deposit, the ore bodies are controlled by faults. The fracture zone mainly strikes NNE - trendign, secondly SN - trending and EW - trending. The deposit was formed in the early stage of tectonic system transformation of East China during the period of from late Juras- sic to early Cretaceous age. The NWW - SEE trending tectonic stress field stransformed the fault structure system formed by the previ- uous nearly NS - trending tectonic stress field, the attitude of the fault system had not been changed actually, but the new mechanical properties were superposed to the fracture system. Based on the study, it pointed out that there is great prospecting potential for pros- pecting in the deposit area, and the key prospecting targets were proposed based on the structural analysis result.