| Guided by mineralization system theory, the thesis focus on the analysis of mineralization factors. On geological setting, author analyzed 'the Great Wall type gold deposits' within the geological setting evolvement of regional and Lengkou basin, from regional geological setting to Lengkou basin, then proceed to the next step- 'the Great Wall type gold deposits' . On study objects, author not only paid attention to the characteristics of gold mineralization of alterated breccia type gold deposits, but also thought much of the comparison with those of other type gold deposits. On research methods, author integrated information of geology, geochemistry, geophysics and remote sensing.Based on the integrative study, author analyzed the ore-controlling factors, discussed the deposit genesis, set up the metallogenic pattern and prognosis model, which would guide the geological exploration in this area. The progresses of study are mainly as follows:1. Author summarized roundly the geological setting of gold deposits, analyzed the characteristics of geological tectonic structure in eastern Hebei. Based on the characteristics of mineralization forms and country rocks, author classified the gold deposits of eastern Hebei into 5 types and 10 sub-types. Author not only summarized the geological characteristics of gold deposits, analyzed the relationship between regional tectonic evolvement and distributing laws of gold, silver, copper, lead and zinc ore deposits, but also set up the metallogenic pattern of eastern Hebei, which built up the basis of the study of geological characteristics and genesis of Lengkou basin gold deposits on metallogenic system theory, these conclusions would guide the geological exploration effectively in study area.2. Author brought forward a new view on the age of Malanyu duplex anticline. There were three kinds of views on the age of Malanyu duplex anticline: first is that Manlanyu-Shanhaiguan was a palaeohigh, and the Malanyu duplex anticline formed in early Mesozoic. Second is that the Malanyu duplex anticline formed in Indo-Chinese epoch(Zhaoyue, 1990, Yangnong, 1996). Third is that Malanyu duplex anticline formed in early stage of middle Yanshanian epoch(J1-J2, Hebei geological bureau, 1988). Studying on stratigraphy, magmatic activities, tectonic evolvement and structure compatibility, author thought that the Malanyu duplex anticline was formed in Indo-Chinese epoch-early Yanshanian epoch (T-J1) by the continuous collision which Siberia Plate pressed the North China Plate from north to south after Mongolia anti-ocean closed. Theseviews about Malanyu anticline are helpful to understand the forming-age and genesis of Malanyu diplex anticline deeply, are benefit for studying the geological setting and tectonic evolvement of Lengkou faults and Lengkou basin.3. Author put forward a new view about the forming-age and genesis of Lengkou faults and Lengkou basin. There were also three views on the problem, first view is that the Lenglou basin was the joint zone of archean Qianxi-Zhunhua terrane and Qianan terrane (Yangwensi, Qiuyoushou, 1998), second view is that the Lengkou faults were basement faults, formed in Dahongyu epoch of middle Proterozoic, these faults were growth faults in early stage, which controlled the forming and development of Lengkou basin, that is to say that Lengkou faults and Lengkou basin were formed in middle Proterozoic (Dingfu, Lizailu etc, 1998), third view is that Lengkou faults and Lengkou basin were formed in late stage of middle Yanshanian epoch(J3, Hebei geological Bureau,1988). Based on the study on characteristics of stratum, comparison of magma, and analysis of tectonic evolvement and stress field, author thought that Lengkou faults were formed in Indo-China epoch to Yanshanian epoch (T-J1) while the Malanyu duplex anticline was forming. Controlled by the Lengkou faults and the Qinglong-Luanxian deep fault, Lengkou basin went through squeezing, rifting and imbalance uplifting in Mesozoic.4. Author studied systematically the relation between tecton...
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