| 锡石硫化物型矿床中黄锡矿成因的实验研究 |
| 点此下载全文 |
| 引用本文：.1990.An experimental study of the origin of stannite in cassiterite sulflde type deposits[J].Mineral Deposits,9(1):49~55 |
| Hits: 2321 |
| Download times: 2057 |
|
|
| 中文摘要:本文用热液实验的方法研究了SnO2(Cs)+2CuFeS2(Cpy) 2H2S=CuFeSnS(St) + FeS2(Py)+2H2O反应形成黄锡矿的可能性及条件。实验研究得出如下几点结论：(1) 在实验条件下锡石与黄铜矿在含硫溶液中反应可以形成黄锡矿或似黄锡矿；(2) 形成黄锡矿的反应受温度和溶液H2S活度的控制，而H2S活度又与热液的酸碱度、氧逸度及硫逸度有关。在极酸的条件下锡石与黄铜矿反应形成的是似黄锡矿，St+Py组合则形成并稳定于弱酸性至中性溶液中，这是典型的热液硫化物矿化环境；(3) 实验结果还表明，Cs+St两个含锡矿物的共生在弱酸至中性热液环境中是可能的。这个环境即富硫及近中性的热液环境，正是大厂锡石硫化物型矿床的成矿环境。 |
| 中文关键词:锡石硫化物型矿床 黄锡矿成因 热液实验 |
| |
| An experimental study of the origin of stannite in cassiterite sulflde type deposits |
|
|
| Abstract:Stannite, a common mineral in cassiterite-sulfide type deposits like Dachng, is often found in close association with or even surrounding cassiterite. It is quite likely that stannite is formed by reaction be, between cssiterite and Fe-Cu sulfides. Nevertheless, few data are available concerning hydrothermal experiment of stannite. Hvdrotherlnal experiments were carried out by the author to ascertain the possibility and the conditions for the formation of stannite by the reaction SnO2(Cs)+2CuFeS2(Cpy) 2H2S=CuFeSnS(St) +FeS2(Py)+2H2O．Experimental work was conducted in high pressure Tuttle Vessels under the condition of 300℃, 600×105pa and pH=1-8, with synthetic cassiterite and chalcopyrite as starting material and H2S-bearing NaCI-HCl or NaF-HF solutions as reaction media. Starting material and solution were both welded in gold capsules, and heating period ranged from 4 to 9 weeks. Experimental products including newly-formed minerals were investigated by X-ray powder diffraction method. Results obtained from more than 20 runs are as follows: 1) stanite for stannoidite and pyrite are formed by reaction betweell cassiterite and chalcopyrite in H2S-bearing solutions under desired conditions. 2) Stannite-forming reaction is controlled by temperature and activities of sulfur species in solutions, which, in turn, are related to pH，fO2 and fS2 and fS2. Cs+Cpy assemblage is stable in alkaline condition. Stannoidite is formed in extremely acid solution, while St+Py assemblage is formed and remains stable in weak acid and neutral solutions, which are normal for hydrothehermal process of sulfides. 3) Cs and Cpy might coexist under the condition of 300℃,600×105 pa and pH=5-8, which is quite typical for cassiterite sulfide type deposits. It is obvious from this study that in cassiterite sulfide type deposits, as stannite is formed by reaction between cassiterite and chalcopyrite, mineralization of sulfides must be later than that of cassiterite. |
| View Full Text View/Add Comment Download reader |
|
|
|
