中文摘要:小西南岔矿床是与燕山期花岗岩有关的斑岩矿床，以金、铜为主，伴有银、铋矿化。金属硫化物主要是黄铁矿、毒砂、磁黄铁矿、黄铜矿。金矿物是金-银系列的自然金、银金矿及金银矿。金的成色低，平均成色728，且变化在305～993这一较大范围内。另外，还发现了碲银矿、硫碲银铋铅矿、自然铋、赫碲铋矿、富硫铋铅矿等多种银、铋矿物。成矿早期只有微弱的铜（钼）矿化，大量金和铜富集于成矿中期( 210～475℃)，而银、铋矿化则出现在成矿作用晚期(160～240℃)。
Abstract:As a porphyry deposit related to Yanshanian granite porphyry, the Xiaoxinancha gold-copper deposit is dominated b}r gold and copper, associated with silver, bismuth as well as weak molybdenum mineralization. Gold-copper (silver-bismuth) orebodies occur in chloritized, sericitized, silicified and carbonatized altered wall rocks; weak molybdenum mineralization exists in the concealed granite porphyry alteration zone. Spatially, mineralization vary approximately in downward succession of gold (silver, bismuth) copper (gold) molybdenum. Ore minerals are rather complex, with the typical metallic sulfides being pyrite, arsenopyrite, pyrrhotite and chalcopyrite. Ores contain fairly abundant arsenopyrite, which is different from character of most porphyry copper deposits, suggesting arsenic concentration of the solution was pretty high at the early ore-forming stage. Gold minerals ars native gold, electrum and kustelite of gold-silver series, and the fineness of gold is in the range of 305~993. Besides native bismuth and minor sulfosalt-heyrovskyite, the silver and bismuth minerals are mainly such tellurides as hessite and hedleyite. The gangue minerals include quartz, calcite, chlorite and sericite. In the ore-forming process, the typical associations of ore minerals formed from early to late are in order of pyrite-arsenopyrite, native gold-pyrite-pyrrhotite-chalcopyrite, and native gold-tellurides of silver and bismuth, suggesting that the formation of ores underwent variation from Fe-As-S to Au-Cu-Fe-S and Au-Ag-Bi-Te systems. Statistics of 600 samples show the existence of certain correlation between gold and copper, with the correlation coefficient being 0.3~0.6. Therefore, gold and copper commonly exhibit similar enrichment characteristics, as mainly finds expression in the fact that they are both obviously concentrated at the quartz-calcite-native gold-chalcopyrite stage of the middle ore-forming phase, and gold tends to be concentrated wherever copper is rich. In spite of this, there exist some differences between gold mineralization and copper mineralization: copper mineralization started at the early biotite (less sulfides) stage, and attained the highest enrichment at the quartz-calcite-native gold-chalcopyrite stage. In contrast, although the highest gold enrichment occurred at the quartz-calcite-native gold-chalcopyrite stage, it continued to the late calcite-quartz-native gold-telluride stage, causing for the second time the enrichment of gold. Silver-bismuth mineralization merely occurred at the late ore-forming stage, namely calcite-quartz-native gold-telluride stage. Ores were formed at 500~160℃ and under 4.5～74 MPa. During the formation of ores, sulfur fugacity tended to decrease with the drop in temperatrure. There are three major ore-forming stages, namely quartz-sercite-pyrite-arsenopyrite, quartz-calcite-native gold-chalcopyrite, and calcite-quartz-native gold-tellurides, and the temperature and sulfur fugacity of these three stages are 500~340℃ and -5～-7, 350～210℃ and - 6.1～-13.9, and 240～160℃ and -9.3～-16.7 respectively.
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基金项目:国家自然科学基金资助项目(49070102)
引用文本：
陈殿芬, 周文茂.1995.吉林小西南岔金铜矿床的金属矿物及矿石特征。[J].矿床地质,14(2):127~149.1995.Ore minerals and characteristics of ores in the Xiaoxinnancha gold-copper deposit, Jinlin Province[J].Mineral Deposits14(2):127~149
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