| The NE-trending Yiwulushan Mountains is located in western Liaoning Province with the Fuxin basin as its western boundary and Xialiaohe depression as its eastern boundary. Our study area belongs to the Fuxin Au-concentrating zoning in northeastern part of the Yanshan intercontinental orogeny in northern margin of the Huabei (North China) Block, where converge the EW-trending Weichang-Chifeng-Fuxin Cu-concentrating zoning in northern Yanshan orogeny and the NE-trending Suizhong-Jinzhou-Fuxin Au-Pb-Zn-Mo mineralization sequence. Thus, it is very important to study the Mesozoic structure in the north segment of the Yiwulushan Mountains, western Liaoning Province and its controlling over the enrichment and distribution of gold deposits. In this dissertation the author mainly discussed the tectonic evolution of the Fuxin Au-concentrating area in the north segment of the Yiwulushan Mountains. The character of the regional structure and its relation to the enrichment of gold deposits since Mesozoic were deeply gone into by the author to provide the basis of regional ore-forming structures for the planning and evaluation as well as exploration of mineral resources.The north segment of the Yiwulushan Mountains, western Liaoning Province is well known because of the discovery of the super-large Paishanlou gold deposit. Based on the study of geological background and structural settings, and with the geological event as the main thread, the author analyzed the development history of the regional ore-forming structures, especially, the new-forming and inherited structural systems since Yanshanian movement, and the range-basin structures of marginal-Pacific ore-forming domain, and the thermo-uplifting structure of the Lushan ore-body as well as the Yiwulushan metamorphic core complex, which are three different scale ore-forming structural systems. The key studied areas are the Paishanlou, Daban, Dayintaogou, Wujiazi gold deposits. In terms of the study of regional structures, geophysics, and geochemistry, and necessary tectono-physical and numerical modeling, as well as studies of ore-forming and ore-controlling structures, the author holds that the detached-ductile shearing zone of the metamorphic core complex is the main ore-controlling structural system, and the regional mineralization is related with the regional ore-forming structural systems which are controlled by compounding of regional structural systems with different time and grade.After three-year hardwork both in field and laboratory, the main advancement achieved is as following:1. According to the study of regional ore-forming structures, the author renewedly expatiated on the evolution history of ore-forming structures. The division of regional structural systems in the study area, the timing and distribution range of the ductile shearing zone and the metamorphic core complex, and their compounding were made by the author in the light of results of the synthetic study on geology in deep, geophysical prospecting, and interpretation ofremote sensing image. The author also suggested that the Fuxin block developed on the base of the geosyncline in the Huabei craton, and had experienced three period process of orogeny, including Hercynian folding orogeny in continental margin, mainly Indo-Sinian to Early Yanshanian intracontinental fold-faulting orogeny, and Late Yanshanian to Early Himalayaian intracontinental range-basin post orogeny.2. Structural systems exposed in the studied area include latitudinal, NS-trending, NW-trending, Cathaysian, Neocathaysian, and rotated- and sheared-related structural systems, the enrichment and formation of gold and multi-metal deposit were tightly related with the formation and development of above-mentioned structural systems. Especially, the compound and joint of those structural systems, and their relation to the geological process in deep, were mainly ore-controlling factors of gold deposits in this area.3. Analyses of small-scale structures, microstructures, X-ray petrofabric showed that the s...
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