摘要:
Each of the Jiaojia and the Sanshandao ore fields in the Jiaodong Peninsula consists of several independent deposits. Recent deep prospecting revealed that the main gold ore bodies in the two ore fields were connected deep down. The shallow and deep prospecting show that the Jiaojia and the Sanshandao are two giant gold deposits with gold reserves amounted to 1200 tons and 1000 tons respectively. The Jiaojia and the Sanshandao giant gold deposits are located along the Jiaojia and the Sanshandao faults, respectively. The main ore bodies of the two giant gold deposits occur at the gentle dip parts of the ore-controlling faults, and form stepped shape of distribution from shallow to deep. The main ore bodies of the Jiaojia giant gold deposit dip SW, lateral prostration to S, and left-handed arrangement. While the main ore bodies of the Sanshandao giant gold deposit dip NE, lateral prostration to N, and right-handed arrangement. Considering the regional geology, formation of the two giant gold deposits and the adjacent gold deposits are genetically related to the contemporaneous granite magmatism (110.6-123 Ma) in the Jiaodong Peninusula. The extensive magma activity provided thermodynamic conditions and some fluid source for gold mineralization. We propose that the gold mineralization in the Jiaodong Peninusula was formed in a thermal uplift-extension tectonic background, and the deposits features and metallogenic setting are unique and different from the other types of gold deposit in the world. In addition, the Tanlu fault cutting deep to the upper mantle might have triggered activity of magmas and fluids, and thus contribute to the gold mineralization.%胶东焦家和三山岛地区过去认为是由若干个独立矿床组成的2个金矿田.近年来深部找矿揭示, 以往确定的浅部金矿床, 其主矿体在深部连为一体.本文通过对浅部和深部找矿成果的综合分析, 提出焦家和三山岛是2个金资源储量分别达1200余吨和1000余吨的巨型金矿床, 二者分别沿焦家和三山岛二条相邻断裂对应产出, 主矿体在剖面上各形成浅部和深部二个缓倾斜的赋矿台阶.焦家巨型金矿床主要金矿体向南西倾伏, 向南侧伏, 呈左列式分布.三山岛巨型金矿床主要金矿体向北东倾伏, 向北侧伏, 呈右列式分布.结合区域地质资料认为, 胶东伟德山型花岗岩的形成时代与焦家和三山岛巨型金矿床及邻区金矿床成矿年龄 (110.6~123 Ma) 相近, 因此, 早白垩世伟德山型花岗岩、崂山型花岗岩、脉岩和青山群火山岩属于成矿期地质体, 大规模岩浆活动为金成矿提供了热动力条件和部分流体来源.分析指出, 胶东型金矿床形成于伸展构造背景, 具有独特的矿床特征和成矿机制, 是不同于国际其他金矿的独特金矿类型;郯庐断裂深切地幔, 可能诱发了成矿期岩浆和流体活动.