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十里坪锑矿床受赵川陆缘隆_滑构造的主滑脱拆离带的控制。矿体呈脉状赋存于韧_脆性主滑脱带上部的脆性次级断层_节理中,矿石类型主要为萤石石英辉锑矿型。围岩为太古宙_元古宙变质岩系,围岩蚀变弱。成矿流体属H2O_CO2_NaCl体系,流体包裹体盐度w(NaCleq)为3.6%～11.3%,均一温度为109～232℃,形成压力大致为800×105Pa。硫、铅同位素研究表明,矿质主要来源于变火山岩围岩;氢、氧同位素显示,成矿流体以大气降水为主,初步将该矿床定为变质岩源就地式大气降水热液矿床。矿石中萤石Sm_Nd等时线年龄为(392±24)Ma,与南秦岭北部晚古生代拗陷区热水喷流_沉积成矿时代相一致,它们都形成于秦岭微板块泥盆纪非造山裂解阶段。
The Shilipping antimony deposit is controlled by the main detachment belt of the Zhaochuan uplift-slip tectonics. The ore bodies are vein-shaped in the brittle subfacies-joints in the upper part of the ductile-brittle main slip zone. The ore types are mainly fluorite quartz stibnite. Surrounding rocks for the Archean _ Proterozoic metamorphic rocks, wall rock weakened. The ore-forming fluid belongs to the system of H2O_CO2_NaCl. The fluid inclusions have a salinity w (NaCleq) of 3.6% ~ 11.3%, a uniform temperature of 109 ~ 232 ℃ and a pressure of about 800 × 10 5 Pa. Sulfur and lead isotope studies show that the mineral originates mainly from volcanic rocks. Hydrogen and oxygen isotopes show that the ore-forming fluid is dominated by atmospheric precipitation, and the deposit is tentatively designated as a metamorphic rock source in situ hydrothermal precipitation. The fluorite Sm_Nd isochron age is (392 ± 24) Ma, consistent with the hydrothermal jet-sedimentary mineralization in the Late Paleozoic depression in the northern part of South Qinling. All of them are formed in the Devonian non-orogenic Cracking stage.