SU Hang^1,2, WEI Wen-biao², TAO Zhi-hua², DAO Xue-qiang², LI Ting-jun³

 

(1. 317 Team, Bureau of Nonferrous Metal Geology of Yunnan Province, Qujing 655000, China;
2. Yunnan Hualian mineral Resource Exploration Lt. Co., Qujing 655000, China;
3. Hualian Zinc & Indium Co. Ltd, Maguan 663701, China)

 

Abstract: Dulong Sn-Zn polymetallic ore deposit, Maguan, Yunnan Province is the 3rd largest scale cassiterite-sulfide deposit in China, and the geological prospecting of the mining area is very important for sustainable development of the company. Major elements, trace elements and rare earth elements and isotopic chronology of the concealed granite in the deep mining area were studied. Results show that the petrochemistry of concealed granite is similar to that of the Late Yanshanian 1st period Laojushan granite, and the rock mass has a LA-ICP-MS zircon U-Pb age of 117.1±0.9 Ma, implying it belonging to the southern Laojunshan granite. The new geological phenomenon has been revealed by the geological exploration in Jinshipo and Lazizhai block in the recent 5 years, showing that the Sn-Zn polymetallic mineralization is related to the Late Yanshanian concealed granite. The granite provided not only the metallogenetic materials, but also the thermal energy, and the detachment faults were the migration channel and the advantageous space of ore-forming elements. It is suggested that the Dulong deposit is a magmatic hydrothermal skarn type deposit related to the Late Yanshanian granite. The geological exploration will focus on the conceal granite in the feature, and the deep mining area and Wukoudong-Yanshan area in the southern mining area are good prospecting potential area.

 

Keywords: Late Yanshanian conceal granite; petrological and geochemical characteristics; Isotopic chronology; Magmatic hydrothermal skarn type deposit; Dulong Sn-Zn polymetallic ore deposit

 

 

ACTA MINERALOGICA SINICA Vol. 36, No. 4, 2016, Page 488-496