永登县鸡冠山石英岩矿地质特征和成因浅析

Geological Characteristics and Genesis of Quartzite Deposit in Jiguanshan,Yongdeng County

永登县鸡冠山石英岩矿赋存于长城系皋兰岩群第三段地层中,属浅变质的海相火山岩—碎屑岩建造,该套地层相变较大,火山岩和碎屑岩在纵横向上频繁交替出现,岩石组合较复杂,沉积厚度大,反映了地槽相的不稳定沉积环境。矿体主要受地层控制,呈层状、似层状产出,NW向主干构造严格控制着矿体的产状、规模及形态,断层沿皋兰岩群与长城系磨石沟组、下奥陶统阴沟群、下白垩统河口群接触带发育。通过总结该矿山石英岩矿的地质特征和成矿机理,为在本区内寻找同类矿山提供借鉴。

Jiguanshan quartzite mine in Yongdeng county is located in the third member of Gaolan group of Changcheng system.In the strata, it is a shallow metamorphic Marine volcanic-clastic formation, which has a large phase transition, volcanic rocks and clastic rocks frequently alternate in the vertical and vertical direction, and the rock assemblages are complexand the sedimentary thickness is large, which reflects the unstable sedimentary environment of geosynclinal facies. The ore bodies are mainly controlled by the structure, which are stratiform and quasi-stratiform. The NW trunk structure strictly controls the occurrence, scale and form of the ore bodies. The faults develop along the contact zone between Gaolan rock group and Moshigou formation of Changcheng system, Yingou group of Lower Ordovician and Hekou group of Lower Cretaceous. According to the geological characteristics and metallogenic mechanism of quartzite ore summarized in this paper, it can provide reference for searching similar mines and carrying out exploration in this area.