中国胶东焦家式金矿类型及其成矿理论

胶东焦家式金矿是中国最重要的金矿类型，是受构造控制的热液型金矿，可分为破碎带蚀变岩型、含金石英脉型、破碎带石英网脉带型、硫化物石英脉型、层间滑动构造带型、蚀变砾岩型和盆缘断裂角砾岩型等亚类。金矿成矿时期为早白垩世，成矿物质来源于强烈的壳幔相互作用，常具有绢英岩化、黄铁矿化、硅化、钾化等矿化蚀变，金矿体产出具有尖灭再现、分支复合、侧伏、斜列、叠瓦规律。岩浆热隆、流体活动、伸展拆离是导致胶东大规模金矿形成的三大关键要素;早白垩世壳幔同熔岩浆活动分凝和激活的围岩流体是金矿迁移、富集的载体;岩浆上隆产生的伸展拆离构造为金矿成矿提供了有利空间。据此，提出了焦家式金矿“热隆-伸展”成矿理论。焦家式金矿形成于早白垩世中国东部岩石圈大规模减薄阶段，受伸展构造系统控制。控矿构造沿倾向呈现陡缓相间的倾角变化规律，金矿主要沿断裂倾角变化的平缓部位和陡、缓转折部位富集，构成“阶梯式”分布型式。

Classification and Metallogenic Theory of the Jiaojia-Style Gold Deposit in Jiaodong Peninsula,China

The Jiaojia-style gold deposit in Jiaodong Peninsula, the most important type of gold deposit in China, belongs to the structure-controlled hydrothermal gold deposit. It can be subdivided into the altered-rock type in the fracture zone, gold-bearing quartz vein type, stockwork quartz vein type along the fracture zone, quartz-sulphide vein type, interlayer type along the detachment belt, altered-conglomerate type and breccia type along the basin margin faults. These types of gold mineralization took place mainly in the Early Cretaceous period. The ore-forming materials were derived from an intensive crust-mantle interaction. The Early Precambrian and Mesozoic ore-hosting rocks were experienced generally phyllic, pyritization, silicification and potassic alteration. Gold bodies are characterized by pinch out, branches, composite, repetition, lateral extension, lateral tilting, echelon and imbrication. The uplifting of hot magma, fluid activities and extensional detachment resulted in the massive formation of gold deposits in Jiaodong Peninsula. The coeval-melted segregation magma and activated fluids derived from the Early Cretaceous crust-mantle interaction are important carriers of migration and enrichment of gold materials. The extensional detachment resulted from magma uplifting provided favorable ore-hosting spaces for the gold mineralization. Therefore, a thermal uplifting-extension-controlled metallogenic theory is proposed. The Jiaojia-style gold deposit was caused by the large-scale thinning of the lithosphere in the Early Cretaceous period in the Eastern China, being controlled by extensional tectonics. The ore-controlling faults have the ladder-style variation from steep to gentle dip angles. The gold deposits are emplaced and enriched at the gentle angle fault segments and the break part from steep to gentle dip angles, displaying a ladder-like distribution pattern.