胶东地区招平断裂带南段构造地球化学特征及找矿方向

胶东是我国最大的金矿集区，已探明金资源储量5000余吨。招平断裂带是胶东地区重要的控矿断裂，通常将其分为北、中、南三段，其中北段、中段目前都赋存大型-特大型金矿床，而南段仅有几个小型矿床。为揭示该断裂带的关键控矿因素，评估其南段成矿潜力，本文以招平断裂带南段为研究对象，通过元素相关性和聚类分析，确定成矿元素共生组合，进而圈定成矿有利地段。结果显示：Au、Bi、Pb、Ag等元素在绢英岩化碎裂岩、绢英岩化花岗质碎裂岩、碎裂状花岗岩中明显富集；糜棱岩中各元素含量与围岩大致相当，富集不明显。相关性分析和聚类分析显示，Au与Bi、Ag、Hg聚为一类，相关性好，是成矿的指示元素。与北段、中段相比，南段糜棱岩和构造片岩发育，南段由南向北韧性变性作用变弱，而脆性破碎逐渐变强。金矿的形成与脆性碎裂关系密切，韧性变形不利于金矿的形成。研究认为南段的北端、南端成矿条件好，具有较好的找矿潜力，而中部不利于成矿，找矿前景不大。

Tectono-geochemical characteristics and prospecting direction of the southern section of the Zhaoping fault zone in the Jiaodong area, Shandong Province

The Jiaodong area of Shandong Province is the largest gold concentration area in China, with proven gold reserves of more than 5000 tons. The Zhaoping fault zone is a major ore controlling structure in this area, which is usually divided into three sections: north, middle and south. At present, large-scale and super large-scale gold deposits have been found in the north and middle sections, while only a few small deposits in the south section. In order to reveal the key ore controlling factors and evaluate the metallogenic potential of the southern segment of the Zhaoping fault zone, the paragenetic association of ore-forming elements is determined by element correlation and cluster analysis, and then the favorable metallogenic areas are delineated. The results show that Au, Bi, Pb, Ag and other elements are obviously enriched in sericitized cataclastic rocks, sericitized granitic cataclastic rocks and cataclastic granites. The contents of elements in mylonite are similar to those in surrounding rocks, but the enrichment is not obvious. Au, Bi, Ag and Hg are clustered into one group with good correlation, which is an indicator element of mineralization. Compared with the north and the middle sections, more mylonite and tectonic schist developed in the south section, the ductile deformation is weakened from south to north, and the brittle fracture is gradually strengthened. The formation of gold deposits is closely related to brittle fracture, and ductile deformation is not favorable to the formation of gold deposits. The study suggests that the northern and southern ends of the southern section of the fault zone have good metallogenic conditions and good prospecting potential, while the central part is not favorable to mineralization, so its ore-search prospect is relatively poor.