关键词: 中国东北, 钼矿床, 成矿时间, 矿床地质, 构造背景

Abstract:

The Northeast (NE) China is located in the combining area of the Central Asian orogenic belt and the circum-pacific orogenic belt, accommodating intensive and complicated mineralizations. The authors summarizes the progresses in exploration and geological research of the Mo deposits in the area, and draws out several conclusions as below: 1)More than seventy Mo deposits have been discovered in NE China, including three world-class giant and eighteen large deposits, with total  resource being next to the eastern Qinling Mo belt; 2)The main genetic types are Mo-bearing porphyry (including explosive breccia pipe) and skarn, and minor of hydrothermal vein; 3)The Mo-associated intrusions are generally Si-and K-enriched calc-alkaline I-type granites, and have been formed by multi-episodic and multistage magmatism; 4)The Mo deposits are concentrated in regions: the northern margin of North China craton, the southern Great Hinggan Range, the northern Great Hinggan Range and the Ji-Hei fold belt; 5)The Mo deposits were formed in multi-episodic and multistage events coinciding magmatic activities, but the majority were formed in Mesozoic, with three peak-mineralization pulses at 250-210, 190-160 and 150-110 Ma, respectively; 6)The Re contents in molybdenites from the Mo deposits are widely variable and generaly low, indicating that the metal sources vary from mantle to crust, but mainly from continental crust; 7)The Re contents in molybdenites and the reserve ratio of Cu/Mo increase along with the metallogenic time of the deposits; 8)The Mo deposits in NE China were formed in subduction-related accretionary orogenesis and continental collision orogenesis (including post-collisional tevtonism), but the Mo-only deposits began to appear in Triassic, i.e. only in continental collision setting (including post-collision).

Key words: Northeast China, molybdenum deposits, metallogenic time, ore geology, tectonic setting