Research On The Regularities Of Tanlu Fault Zone Controls Zhaoyuan Gold Ore Deposits

Zhaoyuan is a main gold production base in China, for over90%gold oredeposits in Jiaodong area are located along Zhaoping Fault and Jiaojia Fault and theareas in between them. However, it still remains a great controversy on whetherthese faults controlling ore deposits, the mechanism of ore-controlling and theevolution characteristics of the fault zones.Based on collecting and summarizing abundant materials of the predecessorresearch results, guided by tectonic diagenetic mineralization theory and taken thefault structure study as the mainline, this paper studies systematically on thecharacteristics of fault structure and the regularities of ore-controlling and proposesthat they belong to the Tanlu Fault Zone. Via a massive amount of field andunderground work, this paper explores the geometric, kinematics and dynamicsfeatures of the two above-mentioned main fault zones, and three tectonic evolutionstages of these faults, i.e early stage as left-lateral slip, interim stage as stretchingnorm slip fault and late stage as thrust compressing have been proposed.Regional fracture fractal dimension value as1.48has been acquired through thecalculation of fault structure fractal dimension value, which manifests that thegeological bodies in this area are in good state of connectivity, thus provideschannels and rooms for the migration of mineral liquids and the enrichment ofore-bodies. The fractal dimension value of the four NNE, NE, near EW, NWtrending fault structures are1.223,1.194,0.864and0.781respectively, which infersthat the NNE trending fault structure is the most complex one with the biggestimpact on mineralization.Using the LA-IPC-MS zircon U-Pb dating techniques on the magmatic rocks inthe main fault zone, the age of the magmatic rocks in the fault zone can be dated at126-132Ma, which is consistent with the leading age of Guojialing rock mass fromprevious work. Therefore, not only the age of Jiaojia fracture extension period hasbeen defined, but also the controlment the faults put on the magmatic rocks has beensuggested.This paper has summarized the location of where the gold ore deposits in TanluFault Zone distributed and the regularities of Tanlu Fault Zone controls the types ofthe gold ore deposits, the sizes of the ore deposits and the ore bodies distributed. Ithas also concluded five favorable ore body occurrence positions, they are fault attitude variance position, fault gouge footwall, branch fault ore of the main fault,tensile fracture and composite part of the fault.