Locating Mechanism of Quartz Vein Gold Deposits in Rushan, Shandong Province

Abstract  According to the differences in ore‐controlling structural systems and the characteristics of host rocks, textures and structures of ores and mineral associations of ores, quartz vein‐type gold deposits in the Rushan area can be divided into the Rushan and Tongling styles. Rushan style gold deposits, occurring in the Kunyushan complex, include Rushan, Tangjiagou and Tongxishan gold mines. They are distributed along four NNE‐trending and sinistral, compresso‐shear faults with a right stepping array. A prominent characteristic of the gold mineralization is that the orebodies in neighbouring gold deposits distributed in a single ore‐controlling fault zone take opposite pitches. Study of the locating structures of the quartz vein gold deposits shows that the Rushan‐style gold deposits are characterized by NNE and NE zoning. Therefore, the intersections of the NE direction of the known gold deposit and the neighbouring NNE‐trending fault zones are favourable for looking for gold deposits, and the ends of the curving segments of sinistral and right‐stepping faults are favourable for looking for large gold deposits. Tongling‐style gold deposits occur in the Sanfosan porphyritic monzonitic granite. Emplacement of gold deposits is controlled by arcuate and radiate structures formed during the intrusion of the Sanfoshan porphyritic monzonitic granite; the radiate faults controlled the distribution of orebodies and the arcuate faults controlled the pitch of the orebodies.