坦桑尼亚克拉通西—西南边缘的乌本迪带一直被视为是一个形成于古元古代的造山带,主要由一系列高级变质、变形的地体组成.该造山带中产出2个大型金矿区,即卢帕金矿田与姆潘达矿区,它们是坦桑尼亚境内仅次于维多利亚湖金矿集区的最重要黄金产地,而且卢帕金矿田内众多矿床(点)很可能属于造山型金矿.近年来,以乌本迪带新元古代榴辉岩的发现为标志,不同研究者相继在乌本迪带的区域构造演化和金成矿作用研究等方面陆续取得了一系列新突破,这表明乌本迪带的实际地质情况远比传统观点认为的更加复杂.本文全面回顾了乌本迪带的内部构造单元划分、地球动力学演化和金矿床成矿作用等研究概况,尤其是系统地总结了前人对乌本迪带在造山作用过程以及金矿成因方面所取得的认识,从而形成了本文最新的研究进展.最后,本文还将乌本迪带的金矿与我国胶东及小秦岭地区的造山型金矿进行了对比研究,并分析了二者之间的异同点,以期为乌本迪造山带下一步基础地质研究及找矿实践提供一些线索或启示.%The Ubendian Belt is considered as an ancient orogenic belt formed during the Paleoproterozoic in the past,which developed around the westernsouthwestern margin of the Archaean Tanzanian Craton.It is mainly composed of several high-grade metamorphic and highly deformed terranes.There are two large gold occurrences in this belt,namely Lupa goldfield and Mpanda Mineral Field,respectively.They are the most important place of production of gold after the famous Lake Victoria area in Tanzania,and many mines of the Lupa Goldfield are most likely belong to the orogenic gold deposits.With the findings of Neoproterozoic eclogite outcrops,a series of new breakthroughs are reported in recent years,primarily on the studies about the tectonic evolution and the gold metallogenesis,all these evidences show that the evolution of the Ubendian Belt is far more complex than the outcomes conclude from the traditional researches.After a comprehensive review of the previous studies,including the divisions of internal tectonic units,geodynamic evolution,gold mineralization,and so on,this paper summarizes the existing views proposed by the former researchers,especially on the process of Ubendian Orogeny and gold mineralization,then it can be used to represent the latest research progresses.Finally,in this paper,the gold mines within the Ubendian Belt are compared with the orogenic gold deposits in Jiaodong and East Qinling (China).It shows there are many similarities or differences between them,the authors also hope this study will throw light on the next step of basic geological researches or prospecting practices.
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