The metallotectonics in Eastern Shandong gold metallogenetic province, China

Based on research into the macro-and micro-structures within the Eastern Shandong gold metallogenetic province, fractures are the main ore-controlling and ore-bearing structures, revealing a process of ductile deformation in the early period and brittle deformation in the later period, when gold mineralization mainly occurred. The ore-bearing structures can be classified into five types: (a) fracture structures; (b) fissure structures; (c) fracture and fissure structures; (d) fracture, fissure and concealed explosion breccia pipe structures; and (e) fracture and explosive breccia structures. NE-trending fractures are the most favourable to the formation of gold orebodies, next in importance are the NNE-trending fractures. NW-trending fractures controlled the distribution and the maximum depth of gold ore shoots during mineralization and intercept the veins with dextral offsets subsequent to mineralization. The different types of orebodies each have their own specific structural controls. Furthermore, the vertical zonation between the auriferous silicified rock and sericite-quartz rock is interpreted as resulting, from convective circulation. The author analyses the areal structural history, sets up a structural model and suggests that the difference between the orebodies in the Zhaoyuan-Yexian and Mupin-Rushan metallogenetic areas results from the distinct structural controls on the ore-bearing fractures in the two areas.