大湖钼金矿床是小秦岭金矿田内一个新的矿床类型-金、钼共生矿床,矿床产于变质核杂岩内的脆韧性剪切带中.金、钼矿体赋存于断裂构造带的不同部位,金和钼含量呈负相关关系,但受同一韧脆性剪切系统控制,矿体均向NE侧伏,该韧脆性剪切带具有多期次构造活动及多次成矿作用特征.通过对硫、铅同位素、成矿流体、成矿物理化学、包裹体成分分析研究可知金矿属于岩浆期后中偏高温热液矿床,成矿时代为燕山期,金矿物质来源为太华群;钼的成矿时代为印支期和燕山期,钼矿物质来源为地壳流体.%Dahu Mo-Au deposit is a new type of deposit in Xiaoqinling goldfield which is Au-Mo intergrowth deposit. It formed in the brittle-ductile shear zone of metamorphism complex rock. Gold orebody mainly occurred in F5 while Mo orebody produced in F35 and F5. Gold and molybdenum orebodies occur in the different place of faulted structure belt independently, and the content of Au and Mo present a negative correlation relationship, but both are controlled by the same brittle-ductile shear zone which has the characteristic of multi-stages tectonic movements and repeated mineralization. The orebodies of Au and Mo lateral trend towards northeast. The surrounding of the orebody exist linear alteration zone, and silicification, sericitization and pyritization connect with gold mineralization while silicification and potassic feldspathization connect with mo mineralization. The contents of constant elements, trace elements and rare-earth elements obtain obvious difference in altered rocks of varying degrees. According to S-Ph isotopes, mineralizing fluid, physical and chemistry of mineralization and the components of enclosure, we can see that the gold mine of this area belonged to medium-high temperature hydrothermal deposit after the magmatic stage, it formed in Yanshan epoch and the substance of gold mine originated from Taihua group while the mineralization period of Mo ore is Indo-Chinese epoch and Yanshan epoch, and the substance of Mo element came from the crust fluid.
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