高峰100号矿体硫、铅同位素特征

The Feature of Sulfur and Lead Isotopes of No.100 Orebody in Gaofeng, Guangxi

10 0号矿体的成矿物理化学环境为 :成矿温度 30 0± 30℃ ;成矿压力为 84.2× 10 5Pa ;LogfO2 =- 30 .4～- 35 .6 ,LogfCO2 =- 2 .5 5～ +0 .36 ,LogfS2 =- 8.3～ - 11.0 ,pH =4.2～ 4.9。同位素的分析结果 :硫化物的硫同位素为 6 4‰～ 12 .3‰ ,δ3 4 SΣS 值为 6 6～ 13 8;2 0 6Pb 2 0 4Pb值为 17 4 91～ 18 96 0 ,2 0 7Pb 2 0 4Pb值为 15 5 39～15 940 ,2 0 8Pb 2 0 4Pb值为 37 95 7～ 39 4 90。表明 10 0号矿体的硫源是混合硫 ,铅源是两种异常铅混合的结果。

The physio-chemical environment of No. 100 orebody is that the main mineralization temperature is about 300±30℃, the pressure is 84.2×10 5Pa, logfo 2 from-30.4 to-35.6,logfco 2 from-2.55 to +0.36, logfs 2 from-8.3 to -11.0,and pH from 4.2 to 4.9. In order to grasp the source of sulfur and lead, the isotope composition of sample was measured. The result is that the sulfur isotope composition for sulfide is from 6.4‰ to 12.3‰, and the ratio of lead isotope is 206Pb/ 204Pb=17.491～18.960, 207Pb/ 204Pb=15.539～15.940, 208Pb/ 204Pb=37.957～39.490. Based on the above data, it is speculated that sulfur came from a mixed source and lead from two unusual lead sources at least.