| 蒙古国南部欧玉陶勒盖铜(金)矿田找矿勘查与成矿理论研究新进展 |
| |
| 关键词:Southern Mongolia Oyu Tolgoi Porphyry copper-gold deposit Hercynian magmatism Geological features |
| 基金项目:国家科技支撑课题(编号: 2007BAB25B02)；地质调查项目(编号: 1212010911029) |
|
| 摘要点击次数: 3588 |
| 全文下载次数: 6658 |
| 摘要: |
| New Advancements in Exploration Practice & Theoretical Studies of the Oyu Tolgoi Copper (Gold) Orefield in the Southern Mongolia |
| The Oyu Tolgoi copper-gold porphyry deposits system in the Turquoise Hill in the Gobi region of the Southern Mongolia is a world-scale super-large copper-gold orefield first discovered in the beginning of this century. Geological exploration results reveal that the present explored gross copper-gold ore resource reaches 3.5 billion tonnes (CuEq at 0.6% as cut-off); the metal resources of copper and gold in the orefield have reached respectively 35.80 million tonnes and 1280 tonnes with average grades respectively at 1.022% and 0.37×10?6 (the highest gold grade at 51.6×10?6), in addition to the inferred molybdenum metal resources of 110,000 tonnes averagely grading at 142×10?6. The Oyu Tolgoi orefield has discovered 8 explored copper-gold porphyry deposits (occurrence); and behind all these figures, the most significant fact is that all the 8 deposits (occurrence) are mostly open to expansion in all directions; that means a tremendous prospective of the Turquoise Hill. Presently, the deposits are under exploitation and the commercial mining is reportedly scheduled in 2013. Some experts believe that the Oyu Tolgoi metallogenic structural corridor, embracing the 8 deposits (occurrence), may represent one single zone of porphyry mineralization, cut by later faults, dykes, and post-mineral intrusions. Research has indicated that the copper-gold mineralization occurs in the Devonian volcanic-sedimentary rocks, and is intimately related to the Hercynian tectonic-magmatic activities in time and space. The geological background of mineralization and the mineral property features of the Oyu Tolgoi copper-gold orefield coincide with that of the typical porphyry cop-per-gold deposits worldwide; and the orefield can thus be classified as the porphyry type copper-gold deposits. The Re-Os isotopic ages of 373~370 Ma from the molybdenite sample stand for the epoch of the porphyry copper mineralization; while the K-Ar ages of 117 Ma and 93 Ma from the two alum samples stand for the time span of copper mineralization in the supergenesis stage. The exploration practice has confirmed the effectiveness of the combination method of ground high-precision magnetic exploration and induced polarization method. The Si-no-Mongolia geological contrastive researches have revealed that the metallogenic belt embracing the Oyu Tolgoi porphyry copper-gold orefield has extended into China’s Alax-Beishan Mountains. The investigation of the exploration history and the successful theoretical studies of the Oyu Tolgoi orefield will offer valuable references for the realization of the exploration breakthrough of copper and gold in China. |
| ZHANG Xin-yuan,NIE Xiu-lan.2010.New Advancements in Exploration Practice & Theoretical Studies of the Oyu Tolgoi Copper (Gold) Orefield in the Southern Mongolia[J].Acta Geoscientica Sinica,31(3):373-382. |
| 查看全文 查看/发表评论 下载PDF阅读器 |