| The Jinchang gold deposites of Dongning County, Heilongjiang province, located at the junction of Taipingling domes and Laoheishan fault basin, lies in the easternmost part of Songnen block of northern orogenic belt. This paper mainly studies the No.18 ore body, comes down to four aspects, including the characteristics of wall-rock alteration, the short-wave infrared spectroscopy technology and magnetic susceptibility of rocks, and the geochemistry characteristics. Primaryunderstandings achieved as follows:1. The wall-rock alteration sequence is feldspathization, silicification, chloritizat- ion, sericitization, calcitization and kaolinite, including propylitic, phyllic and potassic alteration zone from the central to the outword part of the complex. The phyllic zone ranges from -250m to -550m, where gold is enriched in. The gold mineralization occurs mainly in the overlapped part of the argillization and phyllic alteration zone.2. According to the Portable Infrared Mineral Analyzer, the gold mineralization is closely related with the sericitization. The mineral associations of propylitic alteration zone are chlorite + epidote + illite±halloysite±montmorillonite±quartz, the minerals in potassic alteration zone are k-feldspar + kaolinite + halloysite±montmorillonite±quartz, and the minerals in phyllic alteration zone are muscovite + halloysite±montmorillonite±kaolinite±quartz.3. According to the magnetic susceptibility of rocks, diorite's magnetization is much higher than granite's. The decline sequence of the alteration magnetization is: propylitic, phyllic, potassic alteration zone. Magnetic susceptibility is an negative correlation with the Au content, that is, the low magnetization is consistent with the rich ore section.4. According to the geochemistry,the fluid inclusion in quartz of ore body are mainly vapor-rich fluid inclusions. The homogenization temperature of fluid inclusions is mainly larger than 550℃; the main salinity is 43.69 wt% NaCl.eq. proving that jingchang gold deposite is porphyritic gold deposite. Abundant volatiles include H2O, CO2 and CH4 are favorable conditions for mineralization in the region. In addition to magmatic fluid, carbon-oxygen isotopic of calcites suggests that CO2 in the ore-forming fluids was also derived from rainwater. In the course of feldspathization and sericitization, ions of Si4+and K+ are brought into the rocks, while Na+, Ca2+ are brought out from the rocks. Fe3+, Fe2+are brought out from the rocks by feldspathization and then brought into by sericitization. Feldspathization granite and pyrite phyllic rocks have Eu negative anomaly and Ce positive anomaly. The content of Co, Ni, Cu, Ag and Au is positively related, these elements's geochemical anomalies can be used to guide the exploration of geological work.By comprehensive analysis of the results of the study, the author propose several prospecting criterial as fllows:①the overlapped part of the argillization and phyllic alteration zone.②the match part of muscovite's high value and illite's lowe value.③The high thermoelectricity coefficient and compensated thermoelectricity coefficient of P type pyrite.④low intensity and high peak points of thermo-conductivity luminescence of quartz.⑤aera of low magnetic susceptibility.⑥the high value area of Co, Ni, Cu, Ag.
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