Metallogenic series refers to the natural combination of different minerals and different types of deposits formed in different metallogenic periods (and stages) and different geological structures, which are related to certain geological processes or metallogenic events in a geological structural unit and a geological historical development stage.

Metallogenic series can be divided into six levels, namely, metallogenic series combination, metallogenic series type, metallogenic series, metallogenic sub-series, deposit type and deposit (Chen Yuchuan et al., 1994, 1999). The metallogenic series combination is based on three geological processes, namely magmatism, sedimentation and metamorphism. Each geological process is accompanied by corresponding mineralization, which forms various metallogenic series of different geological structural units in different geological periods, and forms metallogenic series combinations related to magmatism, sedimentation and metamorphism. Some deposits related to a certain horizon can temporarily belong to the metallogenic series combination of other deposits after various mineralization superposition or transformation. Metallogenic series types refer to metallogenic series formed in different geological ages and different geological structural units, but with similar geological environment, similar metallogenic characteristics and similar deposit combinations, and with their own time and regional characteristics. The induction of metallogenic series of similar deposits is beneficial to regional metallogenic correlation. Metallogenic series refers to a group of deposits formed in a certain geological age and a certain geological structural unit and related to a certain geological process or metallogenic event, including different minerals and types, but with genetic relations. Metallogenic sub-series refers to the unique mineral deposit combination formed in different metallogenic stages in the secondary structural units within the distribution range of metallogenic series, and the sub-series have genetic relations and obvious * * *. A metallogenic series can be divided into several sub-series or not. The deposit types are summarized from a group of typical deposits with similar metallogenic characteristics, which represents a basic deposit model and contains profound genetic significance. A metallogenic series and sub-series should at least include more than one deposit type. Deposit is the basic unit of metallogenic series, and a deposit type should at least contain more than one deposit.

Metallogenic series is a new concept of ore deposits put forward by Chinese geologist Cheng (1979, 1983). From the point of view of system theory, it studies the basic laws of mineralization in four-dimensional space-time, explores the laws of space-time and material evolution of mineralization in the process of earth evolution, and studies the relationship between various types of deposits in a certain area related to certain metallogenic events and formed in different stages of evolution and under different ore-controlling conditions. Metallogenic series has scientific foresight and high practical value. According to the spatial or temporal characteristics of different types of deposits contained in each metallogenic series and the law that they can be roughly repeated under similar geological background conditions, when a certain type of deposit is discovered in an area, other types of deposits belonging to the same metallogenic series can be predicted and searched. Transition deposits can be found by using the transition laws between two metallogenic series and between two end-member deposits. Applying the concept of metallogenic series to mineral exploration practice can better discuss and expound the regional distribution law and time evolution law of mineral deposits, thus giving full play to the guiding role of metallogenic geological theory in prospecting prediction.

Since Cheng (1979, 1983) and others have successively published important papers such as Preliminary Discussion on Metallogenic Series of Deposits and Re-discussion on Metallogenic Series of Deposits-Also on Metallogenic Series of Some Deposits in Mesozoic, the concept and theory of Metallogenic Series have attracted extensive attention of domestic deposit scholars and mineral exploration workers, and a series of important progress and achievements have been made in the study of regional metallogenic regularity and metallogenic prediction. Chen Yuchuan and Pei introduced the concept and theory of metallogenic series to foreign geologists at the 9th Scientific Seminar of the International Association of Deposit Genesis in 1994 and the 30th International Geological Congress in 1996, which made the concept and theory of metallogenic series formally move towards the international geological science forum and aroused great interest of international geologists.

Since 1980s, Chinese geologists have been working in Nanling area (Chen Yuchuan et al., 1989), iron-copper metallogenic belt in the middle and lower reaches of the Yangtze River (Yin Chang Buddha et al.,1991; Zhai Yusheng et al., 1992), Sanjiang Pb-Zn metallogenic belt (Ye, 199 1), northern Guangxi (Chen Yuchuan et al., 1995), Daxinganling and its adjacent areas (Zhao et al., 1997). 1998) and Altai orogenic belt (Wang et al., 2002), * * * has divided 69 metallogenic series, including 34 Mesozoic metallogenic series (accounting for 49.3%). In 1998, Chen Yuchuan and others divided more than 400 magmatic and metamorphic deposits in the 19 metallogenic belt into 66 metallogenic series, 4 1 metallogenic sub-series and 170 deposit types for the first time in China. In 1999, Chen Yuchuan and others compiled the metallogenic series map of1:500,000 China deposit for the first time, and divided 930 representative deposits in China into 4 metallogenic series combinations and 32 metallogenic series types. 1999 ~ 2003, Xinjiang, Qinghai, Gansu, Ningxia, Shaanxi, Sichuan, Guizhou, Inner Mongolia, Heilongjiang, Jilin, Liaoning, Hebei, Shanxi, Shandong, Henan, Hubei, Hunan, Anhui, Jiangsu, Zhejiang, Jiangxi, Fujian, Guangdong, Guangxi and Hainan and other 25 provinces. These research results and data have important reference value for further dividing and determining the metallogenic series of Mesozoic deposits in China.