Yanshanian (Jurassic-Cretaceous) orogenic processes, magma sources and metallogenesis as well as coal formation in the Taihangshan-Yanshan-West Liaoning region

Abstract：The Taihangshan-Yanshan-West Liaoning region constitutes the Yanshanian Au-Mo-Pb-Zn-Ag-Cu-Fe metallogenic belt and also serves as an important coalfield area in East China. This paper first dealt with isotopic ages of both ore deposits and related intrusive rocks and then selected some relatively reasonable ages for ore deposits as well as ages for coal-formation. Based on the magmatic-tectonic event sequence available, the authors put forward a preliminary scheme for the magmatic-sedimentary-tectonic-metamorphic-metallogenic event sequence. During the pre-orogenic and initial orogenic episode（J1） and the post-orogenic episode（K21）, both the calm tectonics and the warm environment probably served as good geodynamic settings for the formation of large coalfields. During the syn-orogenic episode, the large-scale magmatism might have been a good geodynamic setting for the formation of ore deposits. Magmatism and related mineralization during the early, peak and late orogenic episodes (J2,J3,K11) are also discussed.