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干树金矿是豫西熊耳山西段最重要的金矿之一。主成矿阶段包括黄铁绢英岩以及多金属铁白云石成矿阶段,黄铁绢英岩化蚀变与金矿的关系最密切。主成矿阶段石英中流体包裹体的均一温度为130~388℃,峰值为150~250℃;盐度为6.16%~12.51%,峰值为7%~11%;包裹体液相成分中阳离子主要为Na~+、Ca~(2+),阴离子主要为Cl~–;Na~+/K~+比值为0.17~1.28,平均0.73;F~–/Cl~–比值为0.04~0.06;根据含CO_2包裹体估算成矿压力为90~119 MPa,获得成矿深度为3.3~4.4 km,表明主成矿阶段成矿流体为浅成、中低温、低盐度、富钠钙的岩浆热液。主成矿阶段石英中H、O、C同位素研究显示,成矿流体的δ18O值为0.79‰~6.27‰,平均3.34‰;δD值为–104.1‰~–87.7‰,平均–95.6‰,表明主成矿阶段成矿流体中的水主要源于岩浆水,并混入大气降水,这与流体包裹体的研究结果相吻合。δ~(13)CPDB值为–4.1~–2.7‰,平均–3.4‰,与火成岩或岩浆系统相关,表明可能是在岩浆热液作用下,矿石发生蚀变而形成白云石、方解石等碳酸盐矿物,这与主成矿阶段铁白云石化的发育相吻合。综合研究认为干树金矿床属中低温岩浆热液型金矿床。
Dried tree gold mine is one of the most important gold mines in western section of Xierishan Mountain in western Henan Province. The main metallogenic stages include pyrites and phytonic dolomite metallogenic stages, and the pyritic alteration of pyrites is most closely related to gold deposits. The homogenization temperature of the fluid inclusions in the quartz during the main mineralization is 130 ~ 388 ℃ and the peak value is 150 ~ 250 ℃; the salinity is 6.16% ~ 12.51% and the peak value is 7% ~ 11% The ratio of Na ~ + / K ~ + is 0.17 ~ 1.28, average 0.73; F ~ - / Cl ~ - ratio is 0.04 ~ 0.06; The ore-forming pressure of CO_2 inclusions is estimated to be 90-119 MPa and the ore-forming depth is 3.3-4.4 km, indicating that the ore-forming fluids in the main ore-forming stage are shallow, moderate-low temperature, low salinity and sodium-rich magmatic hydrothermal fluids. The H, O, C isotope studies of quartz in the main metallogenic stage show that the δ18O values of ore-forming fluids range from 0.79 ‰ to 6.27 ‰, with an average of 3.34 ‰ and δD values of -104.1 ‰ to -87.7 ‰ with an average of -95.6 ‰, The water in ore-forming fluid is mainly derived from magmatic water and mixed with precipitation in the ore-forming stage, which is consistent with the study of fluid inclusions. δ ~ (13) CPDB values ranged from -4.1 to -2.7 ‰, with an average of -3.4 ‰, which were related to igneous or magmatic systems, indicating that the ore may have altered under the action of magmatic hydrothermal fluids to form dolomite and calcite Salt minerals, which coincide with the development of iron dolomitization at the main metallogenic stage. Comprehensive study suggests that dry tree gold deposit is a low-temperature magmatic hydrothermal gold deposit.