In this paper, the east ore section of the Pulang porphyry copper deposit is selected as the research object. The micro-thermometer and laser Raman spectroscopic technique are utilized to study the parameters of ore-forming fluids such as pressure, temperature, and compositions. In the meantime, the fractal models, including the perimeter-area (P-A) model and number-size (N-S) model, are introduced to quantify the shape of fluid inclusions, and distinguish the stages of ore-forming fluids, respectively. The results show that the types of fluid inclusions are diversified, namely two-phase liquid-rich type, two-phase vapor-rich type, three-phase CO₂-rich type, three-phase halite-bearing type and pure liquid type. The fluids of main mineralization stage are characterized by medium-high temperature (170.2–421.4 °C), medium-high salinity (9.3 wt.%–33.3 wt.%), and low density (0.73–1.06 g/cm³). With the migration and evolution, the temperature, salinity, and pressure of ore-forming fluids gradually decrease, while the density of fluids increases. The liquid-phase compositions mainly include H₂O, and the vapor-phase compositions consist of H₂O, CH₄, N₂, and CO₂, indicating the characteristics of reducing fluids and the mixing of atmospheric precipitation. In general, the characteristics of ore-forming fluids in the east ore section are similar to those of the first mining area, suggesting that the ore-forming fluids in the east ore section may not migrate from the first mining area. And the east ore section may be a relatively independent metallogenic system. Moreover, the fractal analysis results demonstrate that the shape of fluid inclusions formed in the same hydrothermal activity features self-similarity. The D_AP values of fluid inclusions in B veins, ED veins, and D veins are 1.04, 1.06 and 1.10, respectively, showing a gradually increasing trend from the main stage to the late stage of mineralization. Meanwhile, the shape of fluid inclusions ranging from B veins to D veins becomes increasingly irregular. It also reveals that the homogenization temperature satisfies fractal distribution with four scale-invariant intervals, suggesting that all B veins, ED veins, and D veins have experienced at least four hydrothermal activities. Compared with histogram, the N-S fractal model is able to describe the distribution characteristics of the ore-forming fluids’ homogenization temperature more precisely. Therefore, it presents a potential tool for the stage division of ore-forming fluids. This research provides information about the characteristics of ore-forming fluids in the east ore section of the Pulang porphyry copper deposit, which is beneficial for further exploration in this region, and the extension of the application of fractal models in the study of fluid inclusions. However, further testing of fractal models on the fluid inclusion study is warranted to fully determine the universality.

本文以普朗斑岩型铜矿床东矿段为研究对象。利用微温度计和激光拉曼光谱技术研究成矿流体的参数，例如压力，温度和组成。同时，引入了分形模型，包括外围区域模型（PA）和数量大小模型（NS），以量化流体包裹体的形状，并区分成矿流体的阶段。结果表明，流体包裹体类型多样，即两相富液型，两相富气型，三相CO _2。富油型，三相带盐石型和纯液体型。主要矿化阶段的流体具有中高温（170.2–421.4°C），中高盐度（9.3 wt。％– 33.3 wt。％）和低密度（0.73–1.06 g / cm ³）的特征。随着迁移和演化，成矿流体的温度，盐度和压力逐渐降低，而流体密度增加。液相组成主要包括H ₂ O，气相组成由H ₂ O，CH ₄，N ₂和CO _2组成，表明还原性流体和大气降水混合的特征。通常，东矿段的成矿流体特征与第一矿区相似，这表明东矿段的成矿流体可能不会从第一矿区迁移。东矿段可能是一个相对独立的成矿系统。此外，分形分析结果表明，在相同热液活动中形成的流体包裹体的形状具有自相似性。该d _APB矿脉，ED矿脉和D矿脉中的流体包裹体值分别为1.04、1.06和1.10，显示出从矿化的主要阶段到后期的逐渐增加的趋势。同时，从B脉到D脉的流体包裹体的形状变得越来越不规则。它也表明，均质温度满足四个尺度不变间隔的分形分布，表明所有B脉，ED脉和D脉都经历了至少4次热液活动。与直方图相比，NS分形模型能够更精确地描述成矿流体均质温度的分布特征。因此，它为成矿流体的阶段划分提供了一种潜在的工具。这项研究提供了有关普朗斑岩型铜矿床东矿段成矿流体特征的信息，这有利于该地区的进一步勘探，并扩展了分形模型在流体包裹体研究中的应用范围。但是，有必要对流体包裹体研究中的分形模型进行进一步测试，以完全确定通用性。