Metallogenesis within continental collision zones: Comparisons of modern collisional orogens

作     者：Hongrui ZHANG Zengqian HOU 

作者机构：Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of Geology Chinese Academy of Geological Sciences 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2018年第61卷第12期

页      面：1737-1760页

核心收录：

学科分类：07[理学] 

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 41472067, 41772088, 41320104004, 41773042, 41773043) the China Geological Survey (Grant No. DD20160024) 

主　　题：Pyrenees Alps Zagros Himalaya Collisional orogeny Accretionary orogeny Collisional metallogenesis 

摘      要：Modern collisional orogens represent the natural laboratory for the study of metallogeny in continental collision zones. The Pyrenees, Alps, Zagros and Himalaya are all associated with Neo-Tethyan subduction and represent the youngest collisional orogens on Earth. Here, we compare these four orogens in terms of their composition, architecture, tectonic evolution,and metallogenic systems. The four orogens can be divided into simple and composite types. Simple orogens are represented by the Pyrenees and the Alps, and are characterized by narrow linear shapes in plain view and symmetric structures in cross-section,are free of arc magmatism, and are associated with the Mississippi Valley Valley-type Pb-Zn and orogenic gold deposits. The mineral deposits that form in these simple collisional orogens are generally related to processes that occur in the middle and upper crust. In contrast, composite orogens, as exemplified by the Zagros-Iranian and Himalayan-Tibetan Plateaus, are associated with broad orogenic plateaus in plain view and asymmetrical structures in cross-section, record extensive arc magmatism in continental margins, and are associated with a variety of deposit types including carbonatite-related rare earth element(REE),porphyry Cu-Mo, orogenic Au, Mississippi Valley type Pb-Zn, and detachment-fault-related polymetallic deposits. Although the subduction of Neo-Tethys oceanic crust occurred before the creation of simple collisional orogens in the Pyrenees and the Alps,these areas do not show the record of continental arc magmatism. In contrast, the composite collisional orogens are associated with the development of huge continental margin arcs prior to continental subduction, and the subduction was followed by reactivation of the subduction-modified arc lithospheric material, generating the ore-forming systems in these regions.