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Li和Cl同位素体系有着多种特殊的地球化学特征，是示踪成矿流体来源的重要的非传统稳定同位素手段之一，能够为反演成矿作用过程提供重要的数据支撑。相比于传统示踪成矿流体的同位素体系（e.g., H-O同位素，S同位素），Li作为最轻的金属元素且以氯化物的络合物形式迁移，其同位素体系对流体来源示踪具有代表性。流体包裹体中Cl同位素结合卤素比值（Cl/Br比值）是讨论成矿流体中盐分来源的重要依据。本文主要通过这两种同位素体系开展了多种类型的矿床中成矿流体来源示踪的研究，主要取得了如下成果：①建立了低含量Br和I的ICP-MS测试方法。ICP-MS测试技术相比于传统的离子色谱法（IC法）有着更多的优势（如：低检出限，高灵敏度，耗时少）。然而，ICP-MS在Br测试过程中容易受到多原子团干扰（40Ar39K和40Ar38Ar1H-79Br），导致普通标准模式下测试结果的偏移。在ICP-MS测试过程中，采用KED模式中将He作为碰撞气能够高效的消除样品溶液中的干扰。同时，H-型树脂处理高基体样品能够将样品的的稀释倍数控制在20倍以下，保证低浓度的测试。②建立了不同样品中Li的纯化方法。由于Li和Na在树脂中具有相似的分配系数，纯化Li最重要的步骤的将Na祛除。本文在已公布的Li同位素分离技术的基础上，发现了在树脂量足够的情况下Na击穿的现象。这种现象可能导致单一的层析柱法无法完成纯化Li的目标。目前，建立的2步树脂法能够有效的纯化不同地质样品中的Li，使得纯化后的测试液中的Na/Li小于5，保证Li同位素的测试精准度。通过该方法对标准物质Li分离后，采用MC-ICP-MS测试Li同位素组成，其测试结果与已经公布的同位素测试值在误差范围内保持一致。③金堡石英脉型Zn-Pb矿床的成矿热液可能为岩浆热液来源，不同于区域上广泛分布的MVT型矿床。根据流体包裹体淋滤液成分，成矿热液可分为两种：1）NaCl主导（崩冲，南省，平门矿床）；2）CaCl2主导（平门和排望矿床）。前者的Li同位素组成特征显示成矿热液与深部高度演化的中酸性岩体有关。后者显示出更重的Li同位素组成，可能是岩浆热液与外来流体混合所致。两者的δ37Cl值和Cl/Br比值均显示出岩浆热液的特征。④芦子园Zn-Pb矿床不同成矿期次的矿物中的流体包裹体记录的不同成矿阶段的成矿流体的同位素特征。早期矽卡岩阶段形成的蔷薇辉石的稀土特征和蔷薇辉石流体包裹体淋滤液元素特征，Li和Cl同位素特征均与岩浆热液相关。晚期形成的阳起石淋滤液Li和Cl同位素特征表明矽卡岩晚期阶段可能有大量Li和Cl从流体中进入矿物。热液成矿作用过程中，流体沸腾和少量外来流体的注入可能是导致金属沉淀的原因。⑤铜坑矿区层状矿体和脉状矿体成矿流体在元素与Li同位素组成特征的相似性，表明不同产状的矿体在成因上没有明显的差异。铜坑矿区和高峰矿体与笼箱盖岩体在Li同位素上保持一致，暗示大厂矿田内成矿流体可能为笼箱盖岩体演化过程中出溶的岩浆热液。围岩混入可能是导致部分样品中δ7Li值偏高的原因。铜坑矿区和高峰矿体流体包裹体中Cl/Br比值和δ37Cl值表明了成矿流体在演化过程中发生了相分离过程。⑥川滇黔地区典型MVT型矿床（富乐，会泽，毛坪和天宝山矿床）的流体包裹体Cl/Br比值和δ37Cl值记录了蒸发海水特征。封存在地层中的蒸发卤水在地质应力的驱动下进行长距离的运移，吸收基底地层和沉积盖层中的元素组成，最后在合适的构造位置成矿。 

Lithium (Li) and chloride (Cl) isotopes have unique geochemical signatures. These isotopic systems have been used to trace ore-forming fluids and provide evidences for reconstruction of ore-forming process. Li is the lightest metal elemental and is transported as chloride complexes, similar with other metals, and its isotopic signatures would be more convincing to constrain the fluid sources than other traditional isotopic tools (e.g., H-O isotope，S isotope). Combined with halogen ratios (Cl/Br ratios), Cl isotopes has been widely used to trace the salinity of ore-forming fluids. This work focuses on the sources of ore-forming fluids of different deposits through Li isotopes and Cl isotopes. The main results are as follows:①A newly developed method for the measurement of bromine (Br) and iodine (I) in low- to high salinity aqueous samples by ICP-MS was established. ICP-MS has ICP-MS offers several distinct advantages over IC for Br and I analysis, including higher sensitivity, higher selectivity, lower detection limit. However, it suffered from the isobaric interferences of 40Ar39K and 40Ar38Ar1H on 79Br, resulting in the deviation of measured values in the standard (STD) mode of ICP-MS. The kinetic energy discrimination model (KED mode) of ICP-MS coupled with He as a collision reaction gas has been utilized to minimize the interference caused by the isobaric interferences. High-salinity aqueous samples were further purified to eliminate the matrix effect using H-form cation exchange resin with dilution factor < 20，which make it ideal for the determination of low Br and I concentration.②The Li purification method in different geological samples was established. Separation of Li from Na is the most critical analytical step because Na has a distribution coefficient (Kd) similar to that of Li between stationary and mobile chromatographic phases. Based on the published works, Na breakthrough phenomenon for the enough total resin capacity was found in the chromatographic process, suggesting that single chromatographic process cannot remove Na cleanly in different geological samples. Currently, the established two-step chromatographic purification achieves Na/Li < 5 in final solutions, which ensures the accuracy and precision of lithium isotopes during the determination. The proposed method was validated by the determination of several standard reference materials by MC-ICP-MS, and the measured values are consistent with published values.③The ore-forming fluids of Zn-Pb deposits in the Jinbao mine district sourced from magmatic hydrothermal solutions, which distinguished from MVT deposits in the studied region. According to the components of fluid inclusion leacheates, ore-forming fluids in the mine district could be divided into 2 type: 1) NaCl-dominated fluids, showing lithium isotope signatures similar to evolved magma; 2) CaCl2-dominated fluids, showing heaver lithium isotopic compositions than the former. The fluids could be results of the mixtures between magmatic hydrothermal solution and other fluids. The δ37Cl values and Cl/Br ratios of all fluids are similar to magmatic hydrothermal fluids.④The fluid inclusions hosted in hydrothermal minerals formed in different stages recorded chemical compositions, and Li and Cl isotopic compositions during ore-forming process. The REE of rhodonite and elemental and isotopic compositions (Li and Cl) of fluid inclusion hosed in rhodonite showed that the ore-forming fluids in early stage are related to magmatic hydrothermal solutions. Li isotopes and Cl isotopes fractionation are significant during the form of actinolite, because of the removal of Li and Cl of fluids. Metal precipitation could be triggered by fluid-boiling and mixtures between ore-bearing fluids and other fluids. ⑤There is no difference in elemental composition and Li isotopic compositions of the ore-forming fluids of vein orebodies and stratiform orebodies, implying the same genesis of such orebodies. The lithium isotopic compositions in fluid incluions leachates of Tongkeng mining area and Gaofeng orebody are consistent with that of Longxianggai granites, suggesting that the formation of ore-forming fluids in Dachang deposits would be the results of the exsolution of magmatic hydrothermal solutions from Longxianggai granites. The relationship between Cl/Br ratios and δ37Cl values shows the separation of gas and liquid phase in ore-forming fluids.⑥Cl/Br ratios and Cl isotopic compositions of fluid inclusion leacheates in the MVT deposits (Fule, Huize, Maoping and Tianbaoshan deposit) of Sichuan-Yunnan-Guizhou province is similar to evaporated seawater. Formation brines from evaporated seawater are migrated driving by tectonic activity, assimilate the basement rocks and sedimentary strata, and are located in the feasible structural positon to unload the ore metals.