| Heilongjiang Province is tectonically located among Siberia, North China and Pacific plates. In this area are distributed a great number of ore deposits. On the basis of wide collecting and systematical sorting out a lot of geological and economic geological data, detailed field investigation and comprehensive study have been carried out on the regional geology and ore deposits in the area.The following are the major achievements obtained through this study.1. A new classification scheme of regional strata is proposed, and an analysis of sedimentary environment, sedimentary formations and their relation to mineralization carried out in this paper.2. Volcanic activities are divided into two cycles of Paleo-Asia and continental margin bordering on Pacific, including 6 sub-cycles of the Xingkai, Caledonian, Variscan, Indosinian, Yanshanian and Himalayan, and magmatic intrusive activities into three periods of platform crystallization base formation, Paleo-Asia orogenic movement, and tectonic movement in the active continental margin bordering on Pasific, including 8 stages of the Fuping, Lǔliang, Jinning, Xingkai, Caledonian, Variscan, Indosinian, Yanshanian, and Himalayan. A summarization based on these divisions is made on the characteristics of tectonic setting, lithological associations, and metallogeny in this area.3. Characteristics of metamorphic rocks and their relation to mineralization are ascertained, indicating a close relation of the Early Proterozoic Kongci, Early Proterozoic iron-bearing, Middle Proterozoic mixed ophiolitic, Late Proterozoic Luomahu Group metamorphic, and Late Proterozoic Wolegen Group metamorphic rock series to gold, iron-gold-tungsten, gold, gold-stibium, and copper-lead-zinc mineralization, respectively.4. Features of large deformation structures and their relation to mineralizeation are revealed, showing a close relation of the Middle Proterozoic Taipinggou- Yilan-Muleng, Late Proterozoic Huanyu-Xinlin, Late Paleozoic Hegenshan-Heihe, and Early Mesozoic Wandashan tectonic mixed rock belts as well as the upper Heilongjiang, Ningan Xiaobeihu-Dongweitang, and Jiamusi-Xingkai large tough shearing belts to gold metallogeny.5. Based on summarization of basic tectonic characteristics, lithospheric and tectonic units and tectonic evolution stages are divided, with a focus on major characteristic of different tectonic evolution stages and relation of tectonic evolution to metallogeny. Meanwhile, occurrence of the Xiaoxinganling NW-extending polymetallic tectonic-metallogenic belt on the right bank of Heilongjiang River is proved.6. Distribution areas of the major ore deposits are divided into two metallogenic provinces, including 7 gradeⅢmetallogenic belts that are divided into 29 gradeⅣsub-belts of metallogeny or clusters of ore deposits. Characteristics of 19 metallogenic systems responsible for the formation of the major ore deposits in the area are analysed, leading to proposing several metallogenic models for important metallogenic systems.7. Main types and periods of mineralization are determined, indicating that nonferrous ore deposits are predominated by porphyry and skarn-hydrothermal types and formed in the Xingdong, middle Caledonian, middle to late Variscan, late Indo-Sinian, and middle Yanshanian periods, gold deposits by sedimentary metamorphic-migmatized hydrothermal, superficial middle-low temperature hydrothermal, magmatic hydrothermal, and hot spring types in the Xingdong, late Indo-Sinian, and middle Yanshanian periods, platinum-palladium deposits by magmatic differential type in the late Variscan period, and iron deposits by sedimentary metamorphic, magmatic differential, and skarn-hydrothermal types in the Paleo-Proterozoic, Late Proterozoic, middle Caledonian, late Indo-Sinian, and middle Yanshanian periods.8. New gold and gold- molybdenum deposits have been discovered over the Tongshan copper deposit and in the Wudaogou-Nanshan region, respectively, through this study.
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