An Experimental Study of Oxygen Isotope Fractionation in the Quartz-Wolframite-Water System  

作　　者：张理刚 刘敬秀 等 

机构地区：[1]YichangInstituteofGeologyandMineralResources,ChineseAcademyofGeoscience,Yichang,443003 [2]YichangInstitu

出　　处：《Chinese Journal Of Geochemistry》1993年第3期220-227,共8页中国地球化学学报

基　　金：This projects was financially supported by the National Natural Science Foundation of China.

摘　　要：Oxygen isotope fractionation was experimentally studied in the quartz-wolframite-water systemf rom 200 to 420℃.The starting wolframite was synthexized in aqueous solutions of Na2WOR·2H2O+FeCl2·4H2O or MnCl2·4H2O.The starting solutions range in salinity from 0 to 10 equivalent wt.% NaCl.Experiments were conducted in a gold-lined stainless steel autoclave,with filling degrees of about 50%.The results showed no significant difference in dquilibrium isotope fractionation between water and wolframite,ferberite and huebnerite at the same temperature(310℃）.The equilibrium oxygen isotope fractionation factors of wolframite and water tend to be equal with increasing temperature above 370℃.but to increase significantly with decreasing temperature below 370℃.Oxygen isotope fractionation was experimentally studied in the quartz-wolframite-water system from 200 to 420℃.The starting wolframite was synthesized in aqueous solutions of Na_2WO_4·2H_2O+FeCl_2·4H_2O or MnCl_2·4H_2O.The starting solutions range in salinity from 0 to 10 equivalent wt.% NaCl.Experiments were conducted in a gold-lined stainless steel autoclave, with filling degrees of about 50%.The results showed no significant difference in equilibrium isotope fractionation between water and wolframite,ferberite and huebnerite at the same temperature (310℃).The equilibrium oxygen isotope fractionation factors of wolframite and water tend to be equal with increasing temperature above 370℃,but to increase significantly with decreasing tempera- ture below 370℃: 1000 ln α_(wf)-H_2O=1.03×10~6T^(-2)-4.91(370℃±-200℃) 1000 ln α_(wf)-H_2O=0.21×10~6T^(-2)-2.91(420℃-370℃±)

关 键 词：石英 钨锰铁矿-水体系 温度 压力 氧同位素 热液矿床 

分 类 号：P611.1[天文地球—矿床学] P578.494[天文地球—地质学]