摘要
为探讨沂沭断裂带中段地区金矿的成矿温度和物质来源,对蚀变岩型和石英脉型金矿内方解石、石英中流体包裹体的研究表明,这2类金矿中流体包裹体较为发育,有单一液相包裹体、气液两相包裹体和富气相包裹体等3种类型;其冰点温度为-2～-8.6℃,盐度w(NaCleq)为3.39%～12.39%;其均一温度变化范围较宽,为107～550℃,可分为125～160℃、177～230℃和260～330℃3个温度峰值集中区,分别反映了以中温石英为代表的早期成矿阶段(260～330℃),以中低温石英和方解石为代表的中期成矿阶段(177～260℃)和以低温方解石为代表的晚期成矿阶段(125～160℃)。沂沭断裂带中段地区金矿的流体包裹体特征及其所反映的成矿条件与鲁西金矿相似,而不同于胶东的金矿。沂沭断裂带是鲁西和鲁东构造区之间的一个转换断层,从流体包裹体的特点来看,该断裂带内的金矿与鲁西平邑地区的金矿更为相似。
In order to understand the ore-forming temperature and source materials, this paper studied fluid inclusions well developed within calcite and quartz from both alteration type and quartz vein type gold deposits in the central part of the Yi-Shu fault belt. Three types of fluid inclusions were recognized, namely, single liquid inclusion, gas-liquid inclusion, and gas inclusion. The freezing temperature of the inclusions is about - 2～- 8.6℃, and the salinity w（NaCleq） is 3.39 % ～ 12.39 %. The homogeneous temperatures of the inclusions vary in a wide range of 107～550℃, and can be divided into three temperature concentrated areas, i.e., 125～160℃, 177～230℃ and 260～330℃. These concentrated temperature areas suggest three ore-forming stages, i.e., the early stage represented by the formation of moderate-temperature quartz at 260～330℃, the second stage by low to moderate temperature minerals of quartz and calcite at 177～260℃, and the late stage by low-temperature calcite at 125～160 ℃. The Yi-Shu fault belt is a transform fault between eastern Shandong and western Shandong, and the characteristics of fluid inclusions and mineralization conditions in this area are similar to characteristics of western Shandong, especially to characteristics of the Pingyi gold deposit, but not similar to characteristics of gold deposits in Jiaodong area.
出处
《矿床地质》
CAS
CSCD
北大核心
2007年第6期659-665,共7页
Mineral Deposits
基金
中国地质调查局大调查项目(项目编号:200110200051)资助
关键词
地球化学
沂沭断裂带
金矿
流体包裹体
物质来源
成矿温度
geochemistry, Yi-Shu fault belt, gold deposit, fluid inclusions, source material, ore-forming temperature
