胶东地区除产出大量金矿外，还发现有钼、钨、铜、铅、锌等有色金属矿。为了探讨这些不同矿化类型矿床之间的成生联系，本文对典型矿床特征、成岩成矿时空关系、成矿物质来源和成矿条件等进行了研究。研究表明，成岩成矿时代主要集中在127.6~105 Ma之间，物质来源具有壳幔混合源特点。由胶东东部到西部，表现出金矿床数量渐趋增多，有色金属矿床及与之相关的花岗岩数量和规模逐渐减少的趋势，呈现出由伟德山花岗岩内部向外依次出现钼矿、钼钨矿→铜、银、铅锌、多金属矿→金矿化的特点。金矿赋存于伟德山花岗岩侵位之前的各种围岩中，包括产于较大规模的缓倾断裂中的焦家式破碎带蚀变岩型金矿和产于低序次的陡倾裂隙中的玲珑式石英脉型金矿。有色金属矿成矿显示出“一源、二岩、三带、四化”的矿化规律。胶东金及有色金属矿床具有密切的成因联系，由于形成时的物理化学条件及产出位置的不同，导致了成矿的差异性；它们均为燕山期同一阶段岩浆活动的产物，具有相近的成岩成矿时代，构成了一套与伟德山花岗岩岩浆作用有关的热液矿床成矿系列。岩浆作用、流体活动、伸展构造是成矿的关键因素，在中国东部中生代岩石圈减薄的构造背景下，胶东地区大规模岩浆侵位形成的热隆‒伸展构造为成矿提供了有利空间。成矿过程可概述为：由伟德山花岗岩岩浆分异演化出的流体和幔源流体萃取岩体内部金属元素，形成斑岩‒矽卡岩型钼矿、钼钨矿、铅锌矿床；由围岩中的活化流体、岩浆分异演化流体及幔源流体形成的复合流体，共同萃取花岗岩内部及围岩中的金属元素，形成蚀变岩型、脉型等金矿和脉型多金属矿床。%Besides the famous and extensive gold mineralization, molybdenum, tungsten, copper, lead and zinc ore mineralization are also commonly found in the eastern Shandong Peninsula. In order to delineate the metallogeny of the ore deposits, characteristics of the typical deposits, temporal and spatial relationship of the ore deposits and the plutons, sources of ore-forming material, and ore-forming conditions are studied in this paper. The results show that the age of magmatism and ore-formation is mainly concentrated in the interval of 127.6‒105 Ma, and the ore-forming material was originated from crustal and mantle sources. The density and size of the gold deposits decreased eastward in the eastern Shandong Peninsula, while those of the nonferrous metal deposits increase. The dominant ore metals change from molybdenum and wolfram—copper, lead, zinc, silver, polymetallic to gold from the interior of the Weideshan-type granite to exterior. The gold deposits are commonly occurred in various wall rocks intruded by the Weideshan granite. And the gold deposits include two major types. One is the Jiaojia-type that occurs in the altered rocks commonly related to fracture zones of large and gently-dipping faults. The other is the Linglong-type which occurs as quartz veins in steeply-dipping secondary fractures. The characteristics of the nonferrous metal deposits may conclude as “the same source of metallogenic material, two kinds of surrounding rocks, three types of ore-forming structural zones, and four alteration styles”. Gold and nonferrous metal deposits are closely related genetically in the eastern Shandong Peninsula. The variety of the mineralization is due to different physiochemical condition of ore-formation and location of ore occurrence. These deposits are all the products of the Yanshanian magmatism. Their isotopic ages are very similar and consistent with the age of the Weideshan-type granite. These deposits form a metallogenic series of hydrothermal deposit which is related to the Weideshan-type granite. Based on the analysis above, we conclude that magmatism, fluid activity and extensional structures are key factors for ore-formation. During the lithospheric thinning in the Cretaceous at the Eastern China, the“thermal upwelling-extensional structures”caused by the large-scale magmatism in the eastern Shandong Peninsula provided favorable spaces for mineralization. The course of ore-forming can be summarized as follows: The metallic elements extracted by the magmatic fluids related to the Weideshan-type granite and the mantle-derived fluids, formed the molybdenum, molybdenum-wolfram and lead-zinc deposits of porphyry-skarn type. Whereas the metallic elements extracted by the compound fluids, which are composed of the magmatic fluids, the activated fluids of surrounding rocks and the mantle-derived fluids, formed the altered rocks type and the quartz vein type gold deposits and the vein-type polymetallic deposits.
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