Abstract Different genetic and timing models for gold mineralization in the Kalgoorlie gold camp (Yilgarn craton, Western Australia) suggest either broadly synchronous, late-stage mineralization related to metamorphic fluids at ca. 2640 Ma or a punctuated mineralization history from ca. 2675 to 2640 Ma with the involvement of early magmatic-hydrothermal systems (represented by the Fimiston, Hidden Secret, and Oroya gold-telluride lodes) and late metamorphic fluids (represented by the Mt. Charlotte gold stockwork veins). The results of U-Pb and Sm-Nd geochronological studies of zircon, apatite, and titanite from pre-ore dikes and syn-ore dikes constrain the absolute timing of mineralization and provide new evidence to this timing controversy. Emplacement ages constrained by U-Pb sensitive high-resolution ion microprobe (SHRIMP) zircon data are interpreted to be similar for both the pre-ore dikes (n = 10) and syn-ore dikes (n = 7) at ca. 2675 Ma. An inferred emplacement age of ca. 2675 Ma for the syn-ore dikes is supported by a Sm-Nd isochron age from apatite (laser ablation-inductively coupled plasma-mass spectrometry; LA-ICP-MS) of 2678 ± 15 Ma and by a U-Pb titanite age (LA-ICP-MS) of 2679 ± 6 Ma. The results of chemical abrasion-isotope dilution-thermal ionization mass spectrometry U-Pb zircon analysis from the pre- and syn-ore dikes are complicated by multistage Pb loss, reverse discordance, and potential inheritance. However, the data are compatible with the emplacement of Fimiston/Hidden Secret gold mineralization at ca. 2675 Ma and suggest a younger age for Oroya mineralization at ca. 2665 Ma. These results contrast with models for orogenic gold deposits that invoke broadly synchronous, late-stage mineralization related to metamorphic fluids at ca. 2640 Ma. The bulk of the Kalgoorlie gold camp’s estimated 2,300 t Au endowment was emplaced at ca. 2675 Ma as Fimiston/Hidden Secret Au mineralization. This early Au mineralization was deformed and overprinted twice by subordinate Au mineralization at ca. 2665 (Oroya mineralization) and ca. 2640 Ma (Mt. Charlotte mineralization). Gold mineralization in the Kalgoorlie gold camp was protracted in nature from ca. 2675 to 2640 Ma and reflects the interplay of early magmatic (Fimiston, Hidden Secret, Oroya) and late metamorphic (Mt. Charlotte) hydrothermal fluid systems in the formation of hybrid intrusion-related and metamorphic orebodies.

中文翻译：

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U-Pb 和 Sm-Nd 证据表明西澳大利亚州伊尔加恩克拉通 Kalgoorlie 金营中的偶发造山带金矿化

摘要 卡尔古利金矿营（西澳大利亚州伊尔加恩克拉通）金矿化的不同成因和时间模型表明，与大约 20 年的变质流体有关的广泛同步的晚期矿化。约 2640 Ma 或断断续续的矿化历史。2675 至 2640 Ma，早期岩浆热液系统（以 Fimiston、Hidden Secret 和 Oroya 金碲化物矿脉为代表）和晚期变质流体（以夏洛特山金网脉为代表）的参与。来自前矿脉和同矿脉的锆石、磷灰石和榍石的 U-Pb 和 Sm-Nd 地质年代学研究结果限制了矿化的绝对时间，并为这一时间争议提供了新的证据。受 U-Pb 敏感高分辨率离子微探针 (SHRIMP) 锆石数据约束的侵位年龄被解释为在 ca 的预矿脉 (n = 10) 和同矿脉 (n = 7) 相似。2675 马。推断的就位年龄约。同矿脉的 2675 Ma 由 2678 ± 15 Ma 的磷灰石（激光烧蚀电感耦合等离子体质谱法；LA-ICP-MS）的 Sm-Nd 等时年龄和 U-Pb 榍石年龄支持（ LA-ICP-MS) 为 2679 ± 6 Ma。前矿脉和同矿脉的化学磨损-同位素稀释-热电离质谱U-Pb锆石分析结果因多阶段Pb损失、反向不一致和潜在遗传而变得复杂。然而，这些数据与 ca 的 Fimiston/Hidden Secret 金矿化的位置兼容。2675 Ma，表明奥罗亚矿化的年龄更小。2665 马。这些结果与造山金矿床模型形成对比，造山金矿床模型引发了与 ca. 2640 毫安。Kalgoorlie 黄金营地估计的 2,300 吨金矿藏的大部分位于约 2000 年。2675 Ma 作为 Fimiston/Hidden Secret Au 矿化。这种早期的金矿化在 ca 时被次级金矿化变形和叠印了两次。2665（奥罗亚矿化）和约。2640 Ma（夏洛特山矿化）。Kalgoorlie 金矿营的金矿化在自然界中从 ca. 2675 至 2640 Ma，反映了早期岩浆（Fimiston、Hidden Secret、Oroya）和晚期变质（Mt.