Regional Differences of Gold Deposits on the North China Craton(PDF)
《地球科学与环境学报》[ISSN:1672-6561/CN:61-1423/P]
- Issue:
- 2018年第04期
- Page:
- 363-380
- Research Field:
- 基础地质与矿产地质
- Publishing date:
Info
- Title:
- Regional Differences of Gold Deposits on the North China Craton
- Author(s):
- ZHANG Lian-chang; BAI Yang; ZHU Ming-tian; HUANG Ke
- 1. Key Laboratory of Mineral Resources, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China； 2. Institutions of Earth Science, Chinese Academy of Sciences, Beijing 100029, China; 3. University of Chinese Academy of Sciences, Beijing 100049, China
- Keywords:
- North China Craton; craton destruction; lithospheric thinning; tectonic evolution; Mesozoic; gold deposit; metallogenic difference
- PACS:
- P611
- DOI:
- -
- Abstract:
- The gold mineralization of the North China Craton (NCC) is not uniform. This inhomogeneity mainly is reflected by the spatial dispersity and local concentration, and the multiperiods of goldforming. Gold deposits are mainly converged in Jiaodong, western Shandong, Xiaoqinling, Xiong’er Mountain, eastern Hebei, western and eastern Liaoning and southern Jilin. The northern margin of the NCC is strongly enriched in Au, Mo and Cu, and the southern margin is enriched in Au and Mo, while the eastern margin is characterized by Au. Early period is Au-Mo-Pb-Zn combination, the peak is Au, and the late is Au-Ag combination. Early Cretaceous is the main gold metallogenic epoch of the NCC, then is the Middle-Late Triassic and Jurassic. Generally, the gold mineralization time of Xiaoqinling, Xiong’er Mountain and Taihang Mountain is a little earlier than Jiaodong gold deposit; Jinchangyu, Yu’erya and Niuxinshan gold deposits in the eastern Hebei, as well as Baiyun and Maoling gold deposits in the western Liaoning are formed in Triassic-Jurassic. Overall, the inhomogeneity of gold deposits in the NCC is characterized by the differences of the ore-forming time. The uneven distribution of the NCC gold deposits is comprehensive controlled by the tectonic evolution and interaction of the regional geological bodies, the hydrothermal alteration and gold activation and migration of the metamorphic basement, and the Mesozoic magma activity. In the Middle Jurassic and before, the tectonic evolution of the NCC is mainly influenced by the Central Asian orogenic belt and the Qinling-Dabie orogenic belt. The northern margin of the NCC occurs the transition from extrusion to extension, and in local develops mantle upwelling and lithospheric thinning, and a series of Triassic to Early Jurassic magmatic activities along the EW direction, and even the presence of alkaline rocks, generating a series of Au-Mo-Cu deposits. This is the first craton destruction and gold mineralization event that occurred in the northern margin after the formation of the NCC. In the Cretaceous and after, the geological evolution of the NCC is mainly led by the ancient Pacific Plate. The NCC is subjected to the extensive lithospheric thinning which leads to a more large-scale gold mineralization. In addition, it is found that the ore-forming materials supplied from the metamorphic rock is not entirely dependent on the gold content, but depends on one or more geological processes, which activate and extract gold in the wall-rock, and transport in the hydrothermal fluid, and enrich in a suitable tectonic environment. The influence of granitoids and intermediate-mafic dike rocks in gold deposits seems like a “hot machine”, which is the source of metallogenic hydrothermal fluid (magmatic fluid), and is also a possible source of some ore-forming minerals.
Last Update: 2018-07-27