Xie H.,Sichuan Institute of Metallurgical Geological Exploration |
Tian J.-C.,Chengdu University of Technology |
Wu L.-W.,Institute of Geological Survey of Inner Mongolia |
Zhu Y.-T.,Chengdu University of Technology |
And 4 more authors.
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2011
Aershan area makes up an important section of a polymetallic metallogenic belt in the mid-southern Da Hinggan Mountain. Three types of deposits (ore occurrences) are representative in the area, including hydrothermal vein-type Fe Mn-polymetallic, hydrothermal vein-type Mo (Cu) and skarn-type lead-zinc polymetallic deposits. However, no much attention has been paid on the forming age of their related granites. According to LA-ICP-MS U-Pb isotopic dating, the forming ages of the related ore-forming granites are as the followings: Early Indosinian ((237.8±2.3) Ma) and Middle Yanshanian ((152.2 ± 2.9) Ma), Late Yanshanian ((135.1±0.4) Ma), which are basically comparable with the those of the adjacent Wulanhaote-Suolun region. The Hercynian granite formerly designated is actually the Late Yanshanian granite and the Early Yanshanian granites formerly thought are actually the Early Indosinian and Middle Yanshanian ones. These dating could serve as an important basis for understanding the relationship between the intrusion of the granite magmas and the following hydrothermal polymetallic mineralization both in time and space. The present study is also helpful to comprehending the ages of the ore-forming granites related to different polymetallic mineralization type in the area.
Song J.-F.,Institute of Geological Survey of Inner Mongolia |
Zhang Y.-B.,Institute of Geological Survey of Inner Mongolia |
Xu H.-G.,Institute of Geological Survey of Inner Mongolia |
Zhang F.-S.,Institute of Geological Survey of Inner Mongolia |
Guo G.-F.,Institute of Geological Survey of Inner Mongolia
Northwestern Geology | Year: 2012
The Bayan Tal Mo deposit is located in the Ulji-Oubu La Cu-Au Metallogenic belt, with Mobearing orebodies hosted by the upper Carboniferous Amushan Formation. The shape of orebody is obviously controlled by structures (mainly faults) and formation lithology, and distribution of which is consistent with skarn and hornfelsed rocks. Nowadays, two ore bodies are blocked out. The average grade and highest grade of molybdenum of ore body No. 1-1 is 0.12 × 10 -2 and 8. 55 × 10 -2, respectively, with great variation coefficient, while the average grade of ore body No. 1-2 is 0. 73 × 10 -2. Alteration of this deposit is well developed, of which skarnization and hornfelization are closely associated with Mo mineralization. The geochemical anomalies have the element association of Mo, Au, Ag, Cu, Zn, W, Sn, and Bi, and they are consistent well with each other (abundence of each element in this deposit is four times more than its background value). Both the features of alteration and anomalous elements in the Bayan Tal Mo deposit have the characteristics of skarn deposit.