Wang X.J.,Chinese Academy of science |
Wang X.J.,University of Chinese Academy of Sciences |
Liu Y.P.,Chinese Academy of science |
Miao Y.L.,Yunan Hualian Mineral Resource Exploration Lt. Co. |
And 4 more authors.
Acta Petrologica Sinica | Year: 2014
The Dulong Sn-Zn polymetallic deposit, Yunnan Province, is one of the largest cassiterite-sulfide deposits in China. Being lack of the accurate and reliable geochronological data, the genesis of this deposit is controversial greatly, so that it is very serious to restrict the further development of the geological prospecting. This paper has reported the U-Pb isotope dating of cassiterite by the method of in-situ LA-MC-ICP-MS from the Manjiazhai section of the Dulong ore-field. The result showed that the Pb/Pb-238U/ 207Pb isochron ages of cassiterite samples DL12-716, DL12-722 and DL12-740 were 89. 2 ±4. 1 Ma (N = 22, MSWD = 4. 5), 88. 0 ± 1. 6Ma (N = 24, MSWD = 2. 3) and 87. 2 ± 3. 9Ma (N = 31, MSWD = 14) respectively, and the 207Pb/206 Pb-238 U/ 206 Pb concordia ages of the corresponding cassiterite samples were 96. 6 ± 3. 5Ma (MSWD = 8. 1), 93. 6 ± 1. 6Ma (MSWD =5.8) and 82. 0 ±2. 5 Ma (MSWD = 11) separately. Combining with geology and previous petrogenetic-minerlization geochronology, indicated that the tin minealization of this deposit might mainly be in the Late Cretaceous, which related closely to the later Yanshanian magmatic hydrothermal events. Meanwhile, the basis of the geological facts revealed that the later Yanshanian magmatic hydrothermal events were the key factor of the W-Sn polymetallic deposit mineralization in the Laojunshan area. Moreover, regional geology and geochronology further suggested that there were Late Cretaceous larger-scale granitic magmatism and relative tin mineralization events in the southeastern Yunnan.
Zhang S.-K.,Yunan Hualian mineral Resource Exploration Lt. Co. |
Su H.,Yunan Hualian mineral Resource Exploration Lt. Co. |
Tao Z.-H.,Yunan Hualian mineral Resource Exploration Lt. Co.
Acta Geoscientica Sinica | Year: 2013
The Dulong Sn-Zn polymatallic deposit is one of the largest cassiterite sulfide deposits in China. Geological exploration around the Dulong ore district is very important for the continual development of the mining company. Based on the previous exploration and research achievements, this paper discussed ore-controlling factors. It is suggested that this deposit is controlled jointly by Yanshannian granites, the detachment fault system and the Tianpeng Formation. The Yanshanian Laojunshan granites, which seemed to be the most important factor, provided major ore-forming materials and energy; the detachment fault system was favorable for the movement and precipitation of the ore-forming fluid; the Tianpeng Formation offered the profitable physical and chemical conditions for the concentration of ore-forming materials. On such a basis, the authors hold that this deposit should mainly be of magmatic hydrothermal genesis. The ore-prospecting orientations in the area are also pointed out in this paper.