Ore Geology Reviews最新文献

{"title":"The role of deep-sourced metamorphic fluids in Au enrichment: A case study of the Bangbu Au deposit, southern Tibet (Western China)","authors":"Jian Li , Wen-Yan Cai , Qing-Yi Cui , Hong-Jiang Shi , Kai-Lei Xu , Le Yang , Ming Lei , Kang-Nan Song","doi":"10.1016/j.oregeorev.2025.106699","DOIUrl":"10.1016/j.oregeorev.2025.106699","url":null,"abstract":"<div><div>Accurately identifying the evolutionary process and source of ore-forming fluids is essential for elucidating the mineralization mechanisms of large-scale gold deposits and is pivotal in discerning the genetic types of lode gold deposits. The Bangbu gold deposit (>40 t @ 7.0 g/t), situated in southern Tibet within the eastern segment of the Yarlung Tsangpo metallogenic belt, represents a significant gold repository that originated from the main collision stage of the Tibetan Plateau. This deposit provides an excellent opportunity for examining the genesis of large lode gold deposits within a compressional tectonic environment. The orebodies are predominantly associated with faults systems, while the hosts rock comprise the sedimentary-metamorphic rock of the Langjiexue Group. Petrographic analysis and crosscutting relationships identify three ore-forming stages: (I) quartz + coarse-grained pyrite, (II) quartz + fine-grained pyrite + native gold + polymetallic sulfide, (III) ore-barren calcite. The He and Ar isotopic compositions indicates that the mineralization fluids are of a hybrid crust-mantle origin (<sup>3</sup>He/<sup>4</sup>He = 0.12–0.63 Ra; <sup>40</sup>Ar*/<sup>4</sup>He = 0.27–2.67), with mantle contributions ranging from 1.65 % to 10.93 % (He<sub>mantle</sub>). The hydrogen–oxygen isotope data corroborates the deep-derived metamorphic origin of the ore-forming fluids, aligning with the proposed genetic model. In-situ sulfur isotopic compositions of pyrite (δ<sup>34</sup>S<sub>V-CDT</sub> = +1.82 ‰ to + 5.27 ‰) systematically document mantle reservoir contributions.</div><div>Fluid inclusion (FI) studies identified four FI types in quartz from these stages: liquid (H<sub>2</sub>O)-rich two-phase (L-type), vapor (H<sub>2</sub>O)-rich two-phase (V-type), and CO<sub>2</sub> (liquid and gas)-bearing inclusions (C1- and C2-types). Further identification of four types of fluid inclusion assemblages (FIA), designated as A (L + V-types), B (L + C1-types), C (L + V + C1-types), and D (only L-type). The development of stage I is characterized by four distinct types of FIAs, exhibiting homogenization temperatures from 234 °C to 334 °C and salinities ranging between 2.40 and 6.29 wt% NaCl equivalent. This corresponds to a medium-temperature, low-salinity NaCl–H<sub>2</sub>O–CO<sub>2</sub> hydrothermal system (mol% CO<sub>2</sub> = 7.48–9.21). In contrast, stage II encompasses two types of FIAs (A and D), with homogenization temperatures between 198 °C and 282 °C and salinities from 0.53 to 5.85 wt% NaCl equivalent, indicative of a NaCl–H<sub>2</sub>O-dominated hydrothermal system. Stages I and II pyrite related to native gold, and can be divided into four generations (Py1a, Py1b, Py2a, and Py2b). The porous/sieve-like textures of Py1a and Py2a indicate Au remobilization, predominantly governed by coupled dissolution-reprecipitation (CDR). Elevated As concentrations (up to 1.81 wt%) in pyrite, positively correlated with Au, further de","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106699"},"PeriodicalIF":3.2,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144222303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gold exploration using multi-source remote sensing data in the northern part of the Wa State, Myanmar","authors":"Zhifang Zhao ,&nbsp;Geng Zhang ,&nbsp;Qi Chen ,&nbsp;Dayu Cai ,&nbsp;Fujun Meng ,&nbsp;Xingyue Long ,&nbsp;Tao Zhang ,&nbsp;Yiyang Wang ,&nbsp;Ting Xu ,&nbsp;Haiying Yang ,&nbsp;Lei Miao","doi":"10.1016/j.oregeorev.2025.106703","DOIUrl":"10.1016/j.oregeorev.2025.106703","url":null,"abstract":"<div><div>Gold mining plays a vital role in the economic development of many countries, and Myanmar is known for its rich mineral deposits. Preliminary exploration suggests that the northern region of Wa State in Myanmar is a prospective area for gold mineralization. However, detailed geological investigations are currently lacking, and the target range for mineral exploration remains unclear. Remote sensing technology can provide significant guidance for cross-border mineral exploration. This study developed a multi-source remote sensing methodology to delineate Carlin-type gold deposits in northern Wa State, Myanmar. Landsat 8 OLI and ASTER data were used to interpret fault information. ASTER data were employed to extract iron-stained and silicified alteration information using the iCrosta method. Based on the Google Earth Engine (GEE) platform, lithological classification information was obtained using the random forest method. By comprehensively analyzing the fault, alteration, and lithological information extracted from remote sensing data, two gold exploration target areas were delineated. Taking the No. 1 exploration target area as an example, the pyrite information was further extracted by China’s ZY1-02D hyperspectral data based on spectral angle method, the scope of exploration target area is further narrowed. Through field investigations and petrographic analysis conducted in the narrowed exploration target areas, gold mineralization was indeed identified, demonstrating the effectiveness of the mineral exploration methodology based on multi-source remote sensing data. This study can provide an important reference for the exploration of mineral resources in other similar geological settings worldwide.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106703"},"PeriodicalIF":3.2,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144177736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Remote sensing and aeromagnetic data integration for mapping Cu, Mn, Co, Ba, and Fe Mineralization: A Case study from Aït Semgane, Anti-Atlas, Morocco","authors":"Mohamed Ali El-Omairi ,&nbsp;Abdelkader El Garouani ,&nbsp;Mahmoud Abdellatif ,&nbsp;Manal El Garouani ,&nbsp;Mohammed Boumehdi ,&nbsp;Ali Shebl","doi":"10.1016/j.oregeorev.2025.106701","DOIUrl":"10.1016/j.oregeorev.2025.106701","url":null,"abstract":"<div><div>This study presents a comprehensive exploration of mineralization patterns in the Aït Semgane region of the Anti-Atlas, Morocco, through the integration of remote sensing (Sentinel-2 and PRISMA hyperspectral data), aeromagnetic surveys, field observations and petrographic investigations. The study reveals strong spatial correlations between spectral anomalies, lithological formations, and tectonic structures, highlighting the geological controls on the distribution of copper, manganese, cobalt, baryte, and iron mineralization. Sentinel-2 spectral indices identified key anomalies aligned with major faults and shear zones, particularly within volcanosedimentary (NP3, NP2) and Ouarzazate Group formations, suggesting hydrothermal fluid circulation as a primary mineralization mechanism. PRISMA hyperspectral data enhanced lithological mapping and hydrothermal alteration detection, with spectral analysis Sequential Maximum Angle Convex Cone (SMACC), independent component analysis (ICA), and constrained energy minimization (CEM) techniques identifying alteration minerals and minerals associated with the mineralized zones such as serpentine, baryte, chalcopyrite, and iron oxides. Aeromagnetic data analysis revealed a highly deformed structural framework, with NE-SW, NW-SE, E-W, and N-S trending magnetic anomalies, further corroborating the structural control on mineralization. Field validation confirmed the presence of mineralization in predicted zones, with microscopic analysis revealing mineralogical associations such as malachite, pyrolusite, cobaltite, and hematite. Despite the effectiveness of the integrated approach, the spectral resolution of Sentinel-2 and the limited availability of extensive geochemical datasets suggest opportunities for further refinement. Future detailed remote sensing analysis and advanced geophysical investigations could enhance the accuracy and depth of exploration of the explored zones. This study underscores the value of multidisciplinary data integration for efficient mineral exploration and provides a robust framework for sustainable resource development in structurally complex terrains.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106701"},"PeriodicalIF":3.2,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144147116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of the genesis of typical antimony deposits in the Xiangzhong Antimony Ore Belt, South China","authors":"Lin-Yan Kang ,&nbsp;Jun-Wei Xu ,&nbsp;Xiang-Hua Liu ,&nbsp;Xiang-Fa Song ,&nbsp;Nan-Xing Li ,&nbsp;Bin Li","doi":"10.1016/j.oregeorev.2025.106695","DOIUrl":"10.1016/j.oregeorev.2025.106695","url":null,"abstract":"<div><div>The Xiangzhong Antimony Ore Belt (XAOB), located in the central part of South China, is the most concentrated area of antimony mineralization in the world. However, the genesis of the deposits is still widely disputed. To investigate the ore-forming mechanisms and compare the genetic relationships among different antimony deposits in XAOB, we analyzed the trace element compositions of hydrothermal quartz in six typical deposits (Xikuangshan Sb, Banxi Sb, Woxi Sb-Au-W, Zhazixi Sb-W, Longkou Sb, and Longshan Au-Sb deposits) by <em>fs</em>LA-ICP-MS. The data show that Al, Sb, Ge, Li, Na, and K are the most enriched trace elements in quartz, and the main possible replacement mechanisms in these deposits are (Al³⁺, Sb³⁺) + (Li⁺, Na⁺, K⁺, H⁺) ↔ Si⁴⁺ and Al³⁺ + Ge⁴⁺ + (Li⁺, Na⁺, K⁺, H⁺) ↔ Si⁴⁺. The significant variations in trace element compositions of quartz from the six deposits reveal differences in their ore-forming mechanisms. The Xikuangshan deposit stands out with high Al, Rb, and Sr contents and a limited variation in Al, suggesting that acidic fluids may have facilitated a water–rock reaction. In contrast, quartz from the Woxi deposit shows low Al, Rb, and Sr contents with variations in Ti and Ge contents, indicating fluid boiling may have been responsible for Sb mineralization. Quartz from the Banxi, Zhazixi, Longkou, and Longshan deposits display low, variable Al and variable Ti and Ge contents, suggesting the Sb mineralization was caused by fluid mixing. The magmatic-hydrothermal system likely contributed to Sb mineralization in all deposits except the Xikuangshan deposit. In the Longkou and Longshan deposits, higher B and Ga contents in quartz suggest that a closer relationship with magmatic-hydrothermal system, with Indosinian granite providing both heat and fluids. The XAOB comprises distinct Sb metallogenic systems, which are differentiated by quartz characteristics: (1) the Xikuangshan mineralization system, primarily controlled by water–rock reactions and unrelated to the magmatic-hydrothermal system; (2) the Banxi-Woxi-Zhazixi mineralization system, where the magmatic-hydrothermal system contributed heat; and (3) the Longkou-Longshan mineralization system, granite provided both heat and fluids. This study refines existing metallogenic models for the XAOB and provides valuable insights for future exploration and prospecting.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106695"},"PeriodicalIF":3.2,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neoproterozoic hydrothermally altered zircons reveal ca. 750 Ma post-magmatic overprint and elemental behaviors in the western Yangtze block, South China","authors":"Yanpei Dai ,&nbsp;Shengxian Liang ,&nbsp;Yudi Zhu ,&nbsp;Qing Zhou","doi":"10.1016/j.oregeorev.2025.106696","DOIUrl":"10.1016/j.oregeorev.2025.106696","url":null,"abstract":"<div><div>Geochemical criteria of hydrothermal zircons and behaviors of immobile elements in hydrothermal processes lack systematic investigation. The Neoproterozoic western Yangtze block is featured by long-lasting magmatism, diverse metal deposits and multiple hydrothermal events. Here we report zircon U-Pb-Hf isotope data of two granitoids in this region, to decode the impacts of hydrothermal alteration on zircons. The Shimian monzogranite markedly suffered subsequent alterations, and contains both ca. 807 Ma magmatic zircons and ca. 750 Ma hydrothermally altered zircons. The latter zircon population has diffuse border, spongy texture and mineral inclusions, and exhibits flat LREE patterns and insignificant Ce anomalies (Ce/Ce* = 0.89–3.53). Importantly, their age slightly postdates ca. 764 Ma Kangding tonalite in the periphery, indicating post-magmatic modification and a newfound hydrothermal event in the Neoproterozoic western Yangtze block. All the zircon categories yield ε_Hf(t) values of 2.9–9.6, implying their dominant derivation from juvenile crust. Specifically, ca. 750 Ma hydrothermally altered zircons show superchondritic Y/Ho ratios of 33.6, low log<em>f</em>O₂ values of –17.2 and ΔFMQ of –2.9, indicating fluorine-rich and low oxygen fugacity signatures. When compared with other geochemical criteria, e.g., Th/U and (Sm/La)_N ratios, LREE-I values (LREE-I = Dy/Nd + Dy/Sm) are more reliable for distinguishing hydrothermally altered zircons (LREE &lt; 30) from magmatic ones (LREE &gt; 30). Our integrated data further indicate that LREEs, Th, U and P of zircons are highly mobile in fluorine-rich hydrothermal fluids, and these elements should be discreetly employed for geochemical tracing. In contrast, HREEs, Ti, Nb, Ta, Y, Hf and Hf isotope compositions are hardly modified.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106696"},"PeriodicalIF":3.2,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144147115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New data on the geology and geochronology of the Sarsuk deposit, a Au–bearing VMS deposit in the Ashele Basin, Altay Orogenic Belt, Xinjiang, Northwest China","authors":"Zhenlong Zhang ,&nbsp;Xinxia Geng ,&nbsp;Chengdong Yang ,&nbsp;Chengwen Li ,&nbsp;Ning Li ,&nbsp;Fuquan Yang ,&nbsp;Dongming Wang","doi":"10.1016/j.oregeorev.2025.106700","DOIUrl":"10.1016/j.oregeorev.2025.106700","url":null,"abstract":"<div><div>The Sarsuk polymetallic gold deposit, located in the Ashele Basin of the Chinese Altay Orogenic Belt in the Central Asian Orogenic Belt (CAOB), Xinjiang, China, is a gold–bearing volcanogenic massive sulfide (VMS) deposit. This deposit primarily consists of veins within the rhyolitic porphyry and tuff of the Ashele Formation, with a minor occurrence of stratiform mineralization within the tuff. Chronometric studies of ores at various depths and volcanic rocks in the deposit, suggest that the vein mineralization hosted in the upper rhyolitic porphyry is dated at 383–386 Ma, whereas vein mineralization within the tuff is dated at 387–388 Ma. The veins in the rhyolitic porphyry formed slightly later than the veins that mineralized in the tuff. Additionally, LA–ICP–MS dating of zircons indicates that the basalts of the Ashele Formation formed at 405.7 ± 4.8 Ma, with andesites forming at 403.4 ± 8 Ma, and SHRIMP U–Pb dating reveals that basaltic andesites were formed at 397.5 ± 4.1 Ma. Integrating these findings with those of previous studies indicates that the Sarsuk deposit is a complex VMS deposit that is closely related to regional volcanic activity. The ore-forming processes are divided into an exhalative-sedimentary period, corresponding to mineralization within the volcanic rocks of the Ashele Formation, and a subvolcanic hydrothermal period, associated with the rhyolitic porphyry. The two periods of mineralization are products of the same VMS mineralization system. The Sarsuk polymetallic gold deposit is a product of the main mineralization period of the Altay VMS deposits.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106700"},"PeriodicalIF":3.2,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144147279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of ore-forming fluids of Li-Be deposits and its application to mineral exploration in Middle Altun Region, Xinjiang","authors":"Wang Yong ,&nbsp;Chen Zhengle ,&nbsp;Huo Hailong ,&nbsp;Wang Wei ,&nbsp;Du Xiaofei ,&nbsp;Min Zhuang","doi":"10.1016/j.oregeorev.2025.106691","DOIUrl":"10.1016/j.oregeorev.2025.106691","url":null,"abstract":"<div><div>The Middle Altun region, located at the northern edge of the Tibetan Plateau, constitutes one of China’s vital polymetallic metallogenic belts. Recent discoveries of large to medium-sized pegmatite-type Li-Be deposits, including the Tugeman, South Washixia, Shaliangxi, and Huanglongling sites, have revealed a prolific ∼ 400 km long Li-Be rare metal metallogenic belt. Current research primarily concentrates on the mineralization processes of individual deposits. This study integrates systematic sampling of ore-bearing pegmatite veins from various deposits, utilizing microthermometric analysis of fluid inclusions, laser Raman spectroscopy, and in-situ LA-ICP-MS compositional analysis of quartz in the pegmatites. The aim is to elucidate the temperature–pressure conditions, elemental enrichment characteristics, fluid evolution processes, and mechanisms of metallogenic element precipitation. The results indicate that the ore-forming fluids consist of a medium-temperature, low-salinity H₂O-NaCl-CO₂ system that contains sulfate, carbonate, and chrysotile minerals. LA-ICP-MS in-situ analysis of quartz suggests that the pegmatites in the Tugeman area likely originated from metamorphic-anatectic processes, while those in the West Shaliangxi region are more closely linked to highly fractionated granitic magmatism. The concentrations of elements such as Al, Li, Ti, and Ge in quartz serve as potential indicators for assessing the mineralization potential of pegmatites. Combined analyses of Ti-in-quartz thermometry and other geological evidence suggest that Li-Be mineralization in the Middle Altun region may be structurally influenced by magmatic domes. The southern Tugeman area, located at the dome’s apex, has undergone significant erosion, exposing high-temperature vein systems from the lower orebody. Conversely, the main Tugeman area exhibits limited mineralization, somewhat distal from the dome summit. In contrast, the Shaliangxi and South Washixia regions, which are situated farther from the magmatic domes, show lower degrees of erosion and well-preserved ore bodies, making them promising targets for mineral exploration.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"184 ","pages":"Article 106691"},"PeriodicalIF":3.2,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144263928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quartz textures and compositions of the Axi epithermal gold deposit, Xinjiang, NW China: Implications for coprecipitation mechanism of silica and metals","authors":"Ling Li ,&nbsp;Xuexiang Gu ,&nbsp;Yongmei Zhang ,&nbsp;Yiwei Peng ,&nbsp;Shiyue Yao","doi":"10.1016/j.oregeorev.2025.106680","DOIUrl":"10.1016/j.oregeorev.2025.106680","url":null,"abstract":"<div><div>The textural characteristics of quartz are crucial for understanding the evolution of ore-forming fluids and the mechanisms of mineral precipitation, as they can record hydrothermal physicochemical conditions. The Axi deposit is one of the largest low-sulfidation epithermal gold deposits in the Western Tianshan, Xinjiang, where four ore-forming stages with various quartz textures developed, but the coprecipitation mechanism between quartz and metals remains enigmatic. In this contribution, scanning electron microscope cathodoluminescence (SEM-CL) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) were conducted to study the formation process of these textures and their composition variations. Four generations of quartz were identified: (1) spheroidal, colloform SiO₂ (Qz_1s), and crustiform quartz (Qz_1c) exhibiting oscillatory CL intensity accompanied by bladed ankerite and electrum; (2) cryptocrystalline/mosaic quartz (Qz₂) with dark CL; (3) microcrystalline quartz (Qz₃) coprecipitated with abundant ankerites and sulfides displaying relatively bright CL; (4) euhedral comb/zonal quartz (Qz₄). Integrated studies suggests that the development of these textures is a record of fluctuations in the fluid boiling degree. The coprecipitation of metals and colloidal silica within stages I and III indicates that metal nanoparticles could be mechanically transported with the protection of colloidal silica in hydrothermal solution. Boiling-induced turbulence could enhance the collision and aggregation of colloidal particles, which might be the principal mechanism leading to mineral precipitation. Simultaneously, quartz composition reveals that ore precipitation is always accompanied by a considerable reduction in Al content, which could be ascribed to the fluid degassing-induced escape of acid volatiles (e.g., CO₂, H₂S) and the precipitation of carbonate minerals, thereby leading to an increase in fluid pH. The Al content in the four generations of quartz exhibited a pattern of initial increase followed by a subsequent decrease, represents a multi-stage injection pattern of hydrothermal fluids. In consequence, the variation of Al content quartz might be the fingerprint parameter contributing to the ore precipitation process in the epithermal deposit.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106680"},"PeriodicalIF":3.2,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144177803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Formation of deep brine in the Qaidam Basin, north Qinghai-Xizang Plateau: Constraints from Ca isotopes and geochemistry","authors":"Li Jun ,&nbsp;Zhang Xiying ,&nbsp;Meng Fanwei ,&nbsp;Zhou Lian ,&nbsp;Yuan Xiaolong ,&nbsp;Miao Weiliang ,&nbsp;Yuan Wenhu","doi":"10.1016/j.oregeorev.2025.106676","DOIUrl":"10.1016/j.oregeorev.2025.106676","url":null,"abstract":"<div><div>Ca-rich deep brines in Qaidam Basin (QB) are an important source of lithium, potassium and rubidium. But the initial source of water and mecahnisms of geochemical evolution through interaction with rock hydrothermal systems is still unclear. Ca²⁺ is the dominant elements in deep brines, the sources and enrichment processes are crucial for the correct interpretation of the formation mechanism of deep brines. This brine is an ideal carrier for researching the fractionation mechanism and tracing significance of Ca isotopes in high-salinity deep groundwater, and it is expected to expand the application of Ca isotopes. Ca isotopes and hydrochemistry were studied in deep paleo-brine from the Yahu, Jianshishan, Jianshan, Eboliang and Lenghu anticlinal structures of the Yiliping and Lenghu areas in the middle and north parts of QB respectively. The values of soluble-phase <em>δ</em>^44/40Ca in nine deep brines ranged from 0.59 ‰ to 0.86 ‰, with an average 0.71 ‰. Values of insoluble-phase <em>δ</em>^44/40Ca in six deep brines were 0.80 ‰, and were consistently higher than those of the soluble phase in the same sample because light Ca isotopes diffuse more easily compared to heavy Ca isotope. <em>δ</em>^44/40Ca values of deep brine are lower than those of salt lake water and inter-brine, but close to those of volcanic rocks, carbonates and precipitation. These results indicate that the deep water with significant Ca-enrichment is associated with local hydrothermal activity, including dolomitization and partial calcite dissolution, and the initial water mainly originates from atmospheric precipitation. Hydrochemical analysis shows that leaching evaporite and evaporation process still play a key role in the formation of deep brine. In this study, it is the first time that the <em>δ</em>^44/40Ca data of deep brine in the QB have been reported. It appears that <em>δ</em>^44/40Ca is a good tracer for determining the deep brine origin and the key controlling factors in Ca accumulation processes.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106676"},"PeriodicalIF":3.2,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144105271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-situ trace element and sulfur isotope analyses of sulfides as indicators of ore-forming fluid evolution in the Lakang’e porphyry Mo-Cu deposit, Tibet, China","authors":"Jing Qi ,&nbsp;Guoxiang Chi ,&nbsp;Juxing Tang ,&nbsp;Yumeng Wang ,&nbsp;Pan Tang ,&nbsp;Mengdie Wang","doi":"10.1016/j.oregeorev.2025.106690","DOIUrl":"10.1016/j.oregeorev.2025.106690","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The Lakang’e Mo-Cu deposit is a Mo-dominated porphyry deposit located in the Gangdese metallogenic belt of southern Tibet, which is known for Cu-dominated porphyry deposits such as Jiama and Qulong. The magmatic-hydrothermal evolution responsible for the development of ore-forming fluids in this deposit has not been systematically examined, thus limiting our understanding of the genetic link between Cu and Mo mineralization throughout the metallogenic belt. This study addresses this problem through in-situ analysis of S isotopes and trace elements of pyrite, chalcopyrite and molybdenite from hydrothermal veins of different stages (A, B1, B2, D), which reflect the evolution of the hydrothermal system in terms of S source and temperature, pH and redox condition. The overall range of δ&lt;sup&gt;34&lt;/sup&gt;S&lt;sub&gt;CDT&lt;/sub&gt; values (–7.68 ‰ to +0.75 ‰) of the sulfides and the lack of systematic variation from one stage to another are consistent with a common magmatic source for the sulfur. The decrease of Co/Ni ratios in pyrite from A and B1 to B2 and D veins indicates an overall cooling trend. The elevated As concentrations in sulfides and the lack of calcite in A and B1 veins versus the relatively low As in sulfides and presence of calcite in the D and B2 veins suggest that the fluids became less acidic from early to late stages. The relatively elevated Te concentration in pyrite in B1 and B2 veins compared to those in A and D veins suggests that B1 and B2 veins formed under relatively reducing conditions, whereas A and D veins formed under relatively oxidizing conditions. The consumption of Fe&lt;sup&gt;3+&lt;/sup&gt; due to precipitation of large amounts of magnetite in A vein may be responsible for the decrease in &lt;em&gt;f&lt;/em&gt;O&lt;sub&gt;2&lt;/sub&gt;, which induced significant Mo mineralization in B1 veins. As the hydrothermal system continued to evolve with decreasing temperature and increasing influx of meteoric water, the &lt;em&gt;f&lt;/em&gt;O&lt;sub&gt;2&lt;/sub&gt; increased again, which promoted the precipitation of pyrite-chalcopyrite instead of molybdenite in the D veins. At last, another phase of distinct Mo mineralization may have been triggered by the release of residual metalliferous fluids from a dormant magma chamber due to tectonic reactivation, subsequently migrating upward and forming the B2 veins. Our study highlights the dynamic evolution of magmatic-hydrothermal fluids during the formation of the Lakang’e Mo–Cu deposit and demonstrates that fluid temperature, oxygen fugacity (&lt;em&gt;f&lt;/em&gt;O&lt;sub&gt;2&lt;/sub&gt;), and the involvement of meteoric water were the primary controls on mineralization. Molybdenite precipitation in the B1 and B2 veins was driven by decreasing temperature and &lt;em&gt;f&lt;/em&gt;O&lt;sub&gt;2&lt;/sub&gt;, whereas chalcopyrite precipitation in the D vein was triggered by fluid cooling due to mixing with meteoric water. Such dynamic magmatic-hydrothermal processes may have also operated in other Cu-Mo deposits within the Gangdese metallogenic belt, implying that separate episodes of M","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106690"},"PeriodicalIF":3.2,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144147280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}