Contrasting ore styles and their role in understanding the evolution of the Altaids
Contrasting ore styles and their role in understanding the evolution of the Altaids
复制标题
DOI：
10.1016/j.oregeorev.2016.08.025
复制
发表时间：
2017
影响因子：
3.3
通讯作者：
B. Wan;W. Xiao;B. Windley;Jun Gao;Lianchang Zhang;Keda Cai
中科院分区：
文献类型：
--
作者：
B. Wan;W. Xiao;B. Windley;Jun Gao;Lianchang Zhang;Keda Cai
阿尔泰斯是中亚地区的一座古生代造山带。它占欧亚大陆约10%，是世界上矿藏最丰富的集中地之一，可与环太平洋造山带和特提斯造山带相媲美。特别是，它含有多种对其寄主地体的性质和成因敏感的热液矿床，包括斑岩型铜(金钼)、火山成因块状硫化物铜铅锌和造山型金矿，它们都是会聚大陆边缘、伸展弧型海底盆地和挤压地体边界的诊断标志。在阿尔泰内部，斑岩铜矿床主要集中在哈萨克斯坦和图瓦-蒙古微大陆，从早奥陶世到二叠纪几乎是连续形成的，只有少数是寒武纪和三叠纪，大多数是晚石炭世。大多数火山成因块状硫化物矿床分布在阿尔泰西部的南乌拉尔和鲁德尼-阿拉泰一带，形成于早、中泥盆世的短时间窗内。从新元古代到二叠纪，重要的造山型金矿床沿克拉通、岛弧或微陆边界之间的区域走滑断裂形成，主要形成于早二叠世。在有限的关键地区，火山成因的大量硫化物矿床形成在比同时代斑岩矿床更古老的基岩(>；约100 Ma)上，这表明阿尔泰斯不可能从单一的弧形发展而来。此外，斑岩沉积还勾勒出几个大陆碎片的分布，它们的总面积远远小于阿尔泰斯的面积，这表明岛弧系统中增加了大量新的年轻物质，这些新物质可能已经沉积到周围的大陆边缘。这些局部区域的成矿分布是阿尔泰斯整体构造演化过程中地壳生长机制的结果，与阿尔泰斯是多次俯冲-吸积拼贴的解释相一致。
The Altaids is a Paleozoic orogenic collage in central Asia. It occupies ~ 10% of the Eurasian continent, and it is one of the richest concentrations of mineral deposits in the world, comparable to those of the Circum-Pacific and Tethyan orogenic belts. In particular, it contains many types of hydrothermal ore deposits that are sensitive to the nature and origin of their host terranes, including porphyry copper (gold–molybdenum), volcanogenic massive sulfide copper–lead–zinc and orogenic gold deposits, which are all diagnostic of convergent continental margins, extensional arc-related submarine basins, and transpressional terrane boundaries. Within the Altaids, porphyry copper deposits are mostly concentrated within the Kazakhstan and Tuva–Mongolia micro-continents, where they formed almost continuously from the Early Ordovician to Permian; only a few are Cambrian and Triassic, and most are Late Carboniferous. Most volcanogenic massive sulfide ore deposits are distributed along the South Urals and Rudny Altai in the western Altaids, where they formed in a short time-window from the Early to Middle Devonian. Important orogenic gold deposits formed along regional strike-slip faults between craton, island arc or micro-continent boundaries from the Neoproterozoic to Permian, mostly in the Early Permian. In limited key areas volcanogenic massive sulfide deposits formed upon much older (> 100 Ma) basement rocks than those of coeval porphyry deposits indicating that the Altaids could not have developed from a single arc. Furthermore, the porphyry deposits outline the distribution of several continental fragments, the combined area of which is far less than that of the Altaids, which suggests that extensive new juvenile material has been added into island arc systems, which may have been accreted to surrounding continental margins. These metallogenic distributions in localized areas were a result of the mechanisms of crustal growth within the overall tectonic evolution of the Altaids, and they are consistent with the interpretation that the Altaids is a multiple subduction–accretion collage.