Abstract The Cerro de Pasco district in central Peru hosts one of the world largest porphyry-related epithermal polymetallic deposits. The district is centered onto a large diatreme-dome complex crosscut by numerous dacite to rhyodacite bodies showing domal structures and quartz-monzonite dykes. Three temporally distinct high-temperature porphyry-type mineralization events have been recognized (PM1, PM2, and PM3). Dating of the latter by molybdenite Re-Os and by zircon U-Pb (LA-ICP-MS and CA-ID-TIMS) geochronology complements the already available dataset of zircon U-Pb ages of the subvolcanic and volcanic rocks mostly dacitic in composition occurring in the district and shows the existence of successive short-lived episodes ( 50%) at pressures between 0.9 and 3.4 kbar and at temperatures between ~680 °C and ~725 °C. At such conditions, magma is beyond the point of rheological lock-up and is not eruptible. The emplacement of the mostly dacitic subvolcanic and volcanic rocks has required a series of rejuvenation events of the upper crustal high-crystallinity silicic magma reservoir. Field relationships and geochronology indicate that emplacement of the subvolcanic and volcanic rocks is preceded each time by high-temperature (>600 °C) quartz-pyrite-magnetite ± chalcopyrite and quartz-molybdenite veining forming the three recognized porphyry-type mineralization events. Hydrothermal quartz of these veins host silicate melt inclusions, a rare feature in hydrothermal veins. Their composition determined by LA-ICP-MS analysis indicates that the mineralizing fluids, potentially sourced from intermediate magma recharges, have circulated in a magma reservoir in which the residual interstitial melt was more evolved than the melt trapped as inclusions in the magmatic quartz. The combined geochemical and geochronological data obtained show that several episodes of rejuvenation of a highly crystallized upper-crustal silicic magma reservoir, probably triggered by intermediate magma recharges and by circulation of CO2- and S-rich fluids exsolved from them, are at the origin of the large diatreme-dome complex and porphyry-type mineralization events at Cerro de Pasco.

中文翻译：

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Cerro de Paso（秘鲁）大型硅质圆顶复合体和斑岩型矿化事件起源处的硅质岩浆储层的多次再生事件

摘要 秘鲁中部的 Cerro de Pasco 地区拥有世界上最大的与斑岩相关的浅成热多金属矿床之一。该地区以大量英安岩到流纹英安岩体为中心，形成了一个巨大的圆顶圆顶复合体，显示了圆顶结构和石英-二长岩脉。已识别出三个时间上不同的高温斑岩型矿化事件（PM1、PM2 和 PM3）。通过辉钼矿 Re-Os 和锆石 U-Pb（LA-ICP-MS 和 CA-ID-TIMS）地质年代学对后者进行定年补充了已经可用的次火山岩和火山岩的锆石 U-Pb 年龄数据集，主要成分为英安岩发生在该地区，并显示在 0.9 至 3.4 kbar 之间的压力和~680 °C 至~725 °C 之间的温度下存在连续的短暂发作（50%）。在这样的条件下，岩浆超出了流变锁定点，不会喷发。主要为英安质次火山岩和火山岩的就位需要上地壳高结晶硅质岩浆储层的一系列复兴事件。现场关系和地质年代学表明，每次在次火山岩和火山岩就位之前都是高温（>600°C）石英-黄铁矿-磁铁矿±黄铜矿和石英-辉钼矿脉脉，形成三个公认的斑岩型矿化事件。这些脉的热液石英含有硅酸盐熔体包裹体，这是热液脉中罕见的特征。通过 LA-ICP-MS 分析确定的它们的成分表明，矿化流体可能来自中间岩浆补给，已经在岩浆储层中循环，其中残留的间隙熔体比作为岩浆石英中夹杂物捕获的熔体演化得更多。获得的地球化学和地质年代学综合数据表明，一个高度结晶的上地壳硅质岩浆储层的几次复兴，可能是由中间岩浆补给和从中溶出的富含 CO2 和 S 的流体的循环引发的，是起源于Cerro de Pasco 的大型火山岩圆顶复合体和斑岩型矿化事件。