YE Qin-fu1, ZHANG Suo-qing1, LIU Yun-feng1, YANG Fei-xiang2, TAO Zhi-hua3
(1. Hualian Zinc & Indium Co. Ltd, Maguan 663701，China;
2. The Second Geological Brigade of Bureau of Geology and Mineral Resources Exploration and Development of Yunnan Province, Wenshan 663099, China;
3. Yunnan Hualian Mineral Resource Exploration Co. Ltd., Qujing 655000, China)
Abstract: The Laojunshan metallogenic area is one of the important parts of the southeastern Yunnan-western Guangxi metallogenic province. The Huasitou area in Maguan County is in southwest side of the Laojunshan granite batholith. Yanshanian Laojunshan granites of two stages are exposed in two sides of the Husshitou area in which there are a series of tin-tungsten quartz vein type mineral occurrences. A little geological research of the area has been carried out. The mineralization types in this area include the altered granite-type tungsten-tin mineralization, copper-tungsten mineralization in contact alteration zone and copper-lead-zinc polymetallic mineralization in the strong silicification zone. Types of wall rock alteration include the major greisenization, and minor silicification, potash K-feldspathization, kaolinization, and pyritization. Combined with the new information revealed by recent geological exploration, geological characteristics of tin and tungsten mineralization in the area have been basically summarized in this paper. It is suggested that the W-Sn mineralization was closely related to the late Yanshanian intermediate-acid magmatic intrusion (dominated by the second stage intrusion) in the Huashitou area. The mineralization belongs to the tin-tungsten quartz vein type formed by filling and replacement of the post-magmatic hydrothermal fluid. The late Yanshanian intermediate-acid intrusion, especially the medium to fine grained muscovite-biotite mozongranite of the second stage, is the main controlling factor for the mineralization. The internal and external contact zones between two stage granites and between the intrusion and wall rocks are favorable ore-forming zones. On the basis above, a magmatic hydrothermal W-Sn metallogenic model has been established for the W-Sn mineralization in the Huashitu area.
Keywords: The W-Sn mineralization; Late Yanshanian granite; the Laojunshan metallogenic area; the Huashitou area; Dulong in Yunnan Province
ACTA MINERALOGICA SINICA Vol. 39, No.1, 2019, page 117-125
