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对海沟金矿的断层、节理进行野外和井下研究,应用赤平投影方法对节理产状进行统计与分析,确定研究区节理有6个较为明显的优势产状,构成3个节理系,并进一步确定了3期变形作用的构造应力场。海沟金矿早期受到NW--SE向伸展作用影响,使先存的近EW向海沟断层发生左行走向滑移,在海沟断层上盘形成NE向正断层组合,同时伴有含金石英脉的贯入;中期受到NEE--SWW向挤压作用,NE向正断层组合和发育于断层之中的含金石英脉受到压扭性变形作用的改造;晚期受到NW--SE向挤压作用,海沟断层表现为右行走滑的特征,NE向断层组合再次受到挤压作用改造,同时形成NWW向和NNW向走滑断层,使早期形成的断层和含金石英脉受到变形改造而发生空间上的错位。3期变形作用很可能是自白垩纪以来发生的,与太平洋板块向欧亚大陆的俯冲作用有关。
The fault and joint of Haigou gold mine were studied in the field and downhole. The statics of the joints were calculated and analyzed by using the stereopair projection method. It was found that there were 6 obvious dominant ones in the study area, which formed 3 joint systems and further confirmed The tectonic stress field of Stage 3 deformation. In the early period, the Hailou gold deposit was affected by the NW - SE extensional effect, leading to the left - trending slippage of the preexisting near - EW trending Haitao fault and NE - normal fault assemblage on the Haigou fault, accompanied by the Au - bearing quartz veins In the middle period, NEE - SWW extrusion, NE - normal fault assemblage and gold - bearing quartz vein developed in the fault were transformed by compression - deformation. In the late stage, NW - SE extrusion was applied, The Trench fault is characterized by a right-lateral strike slip. The NE-trending fault assemblage is once again subjected to crustal deformation and NWW-trending and NNW strike-slip faults are formed. The faults and Au-bearing quartz veins formed in the early stage are deformed and spatially transformed dislocation. Stage 3 deformation is likely to have occurred since the Cretaceous, and the subduction of the Pacific plate to the Eurasian continent.