内蒙古柳坝沟一哈达门沟金矿田是华北地台北缘成矿带上的一处以广泛发育钾长石化为特色的超大型金矿田。本文在成矿地质条件分析的基础上,系统研究了柳坝沟、哈达门沟金矿床的氢、氧、碳和硫同位素组成特征,探讨了成矿热液类型和成矿物质来源。研究表明,成矿热液早期以岩浆水或初始岩浆水为主,后期有部分大气降水的加入,且柳坝沟金矿床中大气降水的参与程度更高。热液中碳主要为深源岩浆来源。矿石中硫化物的硫同位素组成特征反映了硫具有地层和岩浆的混合硫特征。柳坝沟金矿床的δ34S值低于哈达门沟金矿床;哈达门沟金矿床东段的δ34S值低于西段,可能反映了柳坝沟金矿床较哈达门沟金矿床剥蚀程度小,哈达门沟会矿床东段较西段剥蚀程度小。
Located in the northern margin of North China Craton, the Liubagou-Hadamengou gold deposit is one of the superlarge ore deposits characterizing by widespread K-feldsparthization. Based on metallogenic setting, this paper has analyzed the composition characteristics of H, O, C and S isotopes and their indicative meaning to the chemistry of the ore fluids and the sources of the ore-forming materials. Hydrogen and oxygen isotopic geochemistry shows that the early ore-forming fluids were mainly derived from magmatie water or initial mixing magmatie water, and also mixed with small amounts of meteoric water. The Liubagou gold deposit had more contribution of meteoric water than the Hadamengou deposit. Carbon isotopie data suggest that the ore-forming materials were mainly derived from deep magma. Sulfur isotopes indicate that the sulfur were derived from the mixture of magmatic and stratigraphie sulfur. The average B34S values of pyrite in the western section are higher than the ones in the eastern part in the Hada- mengou deposit; the overall average δ34S value of pyrite in the Hadamengou deposit is relatively higher than the one in the Liubagou deposit. It implies that the western part was less denudated than the eastern one in the Hadamengou deposit; while there is a less degree of denudation and a better ore prospecting potential for the Liubagou gold depos- it.