Geological characteristics, rock-forming epoch and genesis of the Danizhuang Cu deposit in Luzong basin

The Danizhuang copper deposit is a small porphyry deposit discovered from Luzong basin in recent years. The authors investigated wall rock alterations of the Danizhuang copper deposit on the basis of detailed field observations and petrographic and mineralogical studies, and revealed that the alterations include potassic alteration, beresitization and carbonatization. The characteristics of mineralization, the sequence of mineral deposition and the ore-forming stages, i.e., potassium silicate stage, sulfide stage, carbonate stage, were determined. The sulfide stage can be further divided into quartz sulfide sub-stage and epidote-chlorite sub-stage. The authors collected magmatic rocks (orthophyre) related to mineralization and obtained the age of (126.6± 1.8 Ma) by LA-ICP-MS zircon U-Pb dating, which belongs to Early Cretaceous and was related to the intrusive activity of Shuangmiao Formation. Based on a comparison with similar deposits in other volcanic basins of eastern China, the authors discussed ore-control factors for the formation of this type of deposits, which provides reference for finding porphyry copper deposits in this area.