摘要
In order to date the metallogeny of the Diaoquan silver-copper polymetallic deposit,the authors selected and analyzed six molybdnite samples from this ore deposit.The Re-Os isotopic model ages range from 130.5 Ma to 132.8 Ma,with an isochron age of(131.9±2.9)Ma(MSWD=1.7)and an weighted average age of(132.01 ±0.85)Ma(MSWD=1.05).The molybdnite was formed at 132 Ma,later than the formation of copper minerals.The rock-forming and ore-forming processes of the Diaoquan silver-copper polymetallic deposit took place simultaneously with the Yanshanian volcanic and subvolcanic activities in northeastern Shanxi,which suggests that the sub-volcanic rocks had close relationship with metallogeny and provided metallogenic matter and heat for the Diaoquan silver-copper deposit.The Diaoquan silver-copper polymetallic deposit was formed during the largescale metallogenic activity in the northeast platform and occurred in a continental intraplate tectonic setting.As a result of re-activation of ancient orogeny under the background of thinning of the deep lithosphere,the Diaoquan deposit was formed during the transformation of tectonic regime in the east of the northeast platform.