Ore Geology Reviews最新文献

{"title":"Role of methane-rich fluids in mesothermal gold mineralization: Insights from the Chaihulanzi gold deposit, North China Craton","authors":"Qing–fei Sun ,&nbsp;Ke–yong Wang ,&nbsp;Chen–guang Zhao ,&nbsp;Nan Wang ,&nbsp;Zhi-bo Liu ,&nbsp;Ju-xing Tang ,&nbsp;Bao–ping Gan ,&nbsp;Qiu-ming Pei ,&nbsp;Dong Xu","doi":"10.1016/j.oregeorev.2025.106536","DOIUrl":"10.1016/j.oregeorev.2025.106536","url":null,"abstract":"<div><div>Lode gold deposits in low-grade greenschist belt account for an estimated 40–45 % of the global gold endowment. Au-migrating fluids are commonly metamorphic, low-salinity, and aqueous-carbonic in nature, and flow along high-permeability fault zones where methane-rich fluids may appear under special physicochemical conditions. The Chaihulanzi deposit located in the northern margin of the North China Craton is a large lode Au deposit characterized by abundant methane-rich inclusions. In this study, we examined the nature and isotopic composition of ore-forming fluids to identify their origins, evolution, and roles in Au mineralization. Based on their nature and phase transition patterns, three types of fluid inclusion (FI) were identified: H₂O–NaCl (type I), H₂O–NaCl–CH₄–CO₂ (type II), and CH₄–CO₂ (type III). The primary type I FIs in stage I indicate that the initial hydrothermal fluids were a mesothermal low salinity NaCl–H₂O–CO₂ system. Stage II fluids are characterized by coexisting assemblages of type I, IIa (carbon phase occupying 20–50 vol%), IIb (carbon phase occupying 50–80 vol%), IIIa (CO₂–rich), and IIIb (CH₄–rich) FIs, which display different homogenization modes at similar homogenization temperatures. The wide range of X_CH4 suggests the addition of a foreign methane-rich fluid, indicating that the ore-forming fluids evolved into a medium-to-low-temperature and low-salinity NaCl–H₂O–CH₄–CO₂ system. Abundant CH₄–rich FIs in stage III indicate that the fluid was transformed into a medium-to-low temperature and low-salinity NaCl–H₂O–CH₄ ± CO₂ system. The properties of stage IV FIs indicated a low-temperature and low-salinity NaCl–H₂O system. The H–O–C isotope data of stage I suggest that the primary fluids were derived from a dominant magmatic origin. The increasingly depleted H–O–C isotope data indicate the progressive involvement of a foreign methane-rich fluid in stage II. The fluids in stage III show an increased degree of fluid mixing. In conclusion, our data confirmed that the primary ore-forming fluids were oxidizing mesothermal low-salinity NaCl–H₂O–CO₂ systems. With the mixing process of wall-rock buffered fluids, the main metallogenic stage fluids evolved into a reductive medium-to-low temperature and low-salinity NaCl–H₂O–CH₄–CO₂ system. The precipitation of Au was attributed to the combined effects of phase separation, reducing methane agent, and sulfidation of iron-containing minerals.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106536"},"PeriodicalIF":3.2,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Translation of mineral system components into time step-based ore-forming events and evidence maps for mineral exploration: Intelligent mineral prospectivity mapping through adaptation of recurrent neural networks and random forest algorithm","authors":"Soran Qaderi ,&nbsp;Abbas Maghsoudi ,&nbsp;Mahyar Yousefi ,&nbsp;Amin Beiranvand Pour","doi":"10.1016/j.oregeorev.2025.106537","DOIUrl":"10.1016/j.oregeorev.2025.106537","url":null,"abstract":"<div><div>In the integration step of conventional mineral prospectivity analysis approaches chronology of ore-forming subsystems is ignored leading to less reliable predictions. In this paper, we design and adapt recurrent neural network architectures, which have the ability of modelling sequence-related natural events, and a random forest algorithm to bring the temporal nature of ore-forming subsystems into prospectivity analysis procedure and to mitigate the aforementioned issue. A dataset of Pb-Zn mineralization in Semnan Province, Iran, is used to illustrate the procedure. The exploration targets in the prospectivity maps show excellent agreement with the deposit locations, demonstrating the importance of incorporating the chronology of ore-forming geological processes in targeting mineral deposits. This study links our understanding of the chronology of mineral system parameters to predictive modeling to support decision-making in mineral exploration targeting.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106537"},"PeriodicalIF":3.2,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chalcopyrite geochemistry: Advancements and implications in ore deposit research","authors":"Yao Tang ,&nbsp;Deyou Sun ,&nbsp;Jun Gou ,&nbsp;Xinran Ni ,&nbsp;Xiaohui Zeng ,&nbsp;Xingmin Zhang ,&nbsp;Weipeng Liu ,&nbsp;Shanshan Liang ,&nbsp;Changzhou Deng","doi":"10.1016/j.oregeorev.2025.106528","DOIUrl":"10.1016/j.oregeorev.2025.106528","url":null,"abstract":"<div><div>Chalcopyrite is a prevalent sulfide mineral in ore deposits and hosts various trace elements such as Ag, Co, As, Se, Sb, Te, Bi, etc. The variations in trace element contents, as well as Fe, S, and Cu isotopic compositions of chalcopyrite are controlled by a series of factors including metallogenic temperature and pressure, fluid compositions, metal sources, and sulfide equilibrium. Therefore, chalcopyrite geochemistry offers valuable insights into the genesis of ore deposits. In this study, we reviewed and compiled the chalcopyrite geochemical data from porphyry Cu deposits (PCDs), sedimentary rock-hosted stratiform Cu deposits (SSCs), iron oxide Cu-Au deposits (IOCGs), sedimentary exhalative deposits (SEDEXs), magmatic Cu-Ni sulfide deposits (MSDs), and volcanogenic massive sulfide deposits (VMSs), etc. We aim to discuss and summarize the distribution and control mechanisms of trace elements and the compositional characteristics and controlling factors of S, Fe, and Cu isotopes in chalcopyrite, and the application of chalcopyrite geochemistry in ore deposit studies. Our study shows that different types of ore deposits show significantly distinct chalcopyrite geochemical characteristics. For example, in PCDs, chalcopyrite is notably enriched in Zn and Pb, with negative δ³⁴S values (−2.1 ± 3.64 ‰, n = 32) due to sediment contributions. Positive δ⁶⁵Cu values (1.5 ± 2.00 ‰, n = 140) indicate a mantle-crustal mixed source, while negative δ⁵⁷Fe values (−4.3 ± 5.10 ‰, n = 32) likely result from Fe isotope fractionation during magnetite precipitation or continental crust contamination. In MSDs, Cr is the most enriched element, with positive δ³⁴S values (1.0 ± 2.14 ‰, n = 185) and slightly negative δ⁶⁵Cu values (−0.46 ± 0.50 ‰, n = 52). Chalcopyrite in SSCs is enriched in Zn and As, characterized by negative δ³⁴S (−3.6 ± 0.12 ‰, n = 190) and δ⁶⁵Cu values (−0.59 ± 0.98 ‰, n = 118). These findings indicate that chalcopyrite can be used as an impactful tool for constraining metallogenic physical and chemical conditions, discriminating ore deposit types and tracing the evolution of ore-forming fluids and metal sources.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106528"},"PeriodicalIF":3.2,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143511339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Early Cretaceous Tin-polymetallic system: The Baiyinchagan giant deposit in the southern Great Xing’an Range, North China","authors":"Wenbao Zheng ,&nbsp;Xiang Ji ,&nbsp;Monique Tang ,&nbsp;Zhiguang Chen ,&nbsp;Zhiqiang Zhang ,&nbsp;Qicai Wang","doi":"10.1016/j.oregeorev.2025.106527","DOIUrl":"10.1016/j.oregeorev.2025.106527","url":null,"abstract":"&lt;div&gt;&lt;div&gt;A critical metal, tin’s mineral resources are progressively becoming scarcer. The classification of Sn deposits is intricate, and porphyry Sn deposits are less common than porphyry Cu-Mo deposits. Sn mineralization has taken place from the Proterozoic era to the Cenozoic era, during which the mineralization ages of world-class Sn deposits in regions such as Nanling, Youjiang-Guibei, and the southern Great Xing’an Range within China are predominantly concentrated in the Late Jurassic-Early Cretaceous period.&lt;/div&gt;&lt;div&gt;The Baiyinchagan deposit stands as a colossal porphyry-hydrothermal vein-epithermal Sn polymetallic system in the southern Great Xing’an Range. This system encompasses porphyry Sn-Cu-Ag, hydrothermal vein Sn-Ag, and epithermal Ag. The verified resources amount to 0.35 Mt of Sn at a grade of 0.75 %, 727 Moz of Ag at 164 g/t, 0.9 Mt of Pb plus Zn at 4.8 %, 0.2 Mt of Sb at 0.32 %, 0.1 Mt of Cu at 0.2 % and 3839 t of Ga at 51 g/t. Porphyry-type alterations which encompass quartz-sericite-tourmaline-muscovite and epidote-chlorite-tourmaline, are respectively correlated with the disseminated-veinlet cassiterite, chalcopyrite, arsenopyrite and tetrahedrite ore mineral assemblages, as well as low-grade disseminated cassiterite mineralization. The alterations in hydrothermal Sn polymetallic veins are typified by quartz-fluorite-tourmaline veinlets and disseminated tourmaline-sericite, all of which are associated with veinlet-stockwork, brecciated and disseminated cassiterite, chalcopyrite, sphalerite, tetrahedrite and arsenopyrite. The alterations in hydrothermal Ag polymetallic veins consist of quartz-calcite/siderite and chlorite, and is intimately related to brecciated sphalerite, galena, chalcopyrite, jamesonite and pyrite. Epithermal alteration includes quartz-illite-siderite, sericite-kaolinite and epidote-chlorite-fluorite. Sphalerite, galena, pyrargyrite, argentite and pyrite are frequently disseminated and exhibit a close relationship with quartz-illite-siderite alteration.&lt;/div&gt;&lt;div&gt;The petrological and geochemical traits of the Sn-Cu-Ag-bearing porphyry, quartz porphyry, albite porphyry and rhyolite within the Baiyinchagan deposit bear resemblance to those of igneous rocks in other Sn deposits in the southern Great Xing’an Range and are characteristics of A-type granites that formed in intraplate environments. The zircon Hf isotopic and trace element features of the Sn-Cu-Ag-bearing porphyry and quartz porphyry imply that the magmas were generated through partial melting of the crust with certain mantle contributions. The zircon U-Pb age of the Sn-Cu-Ag porphyry, cassiterite U-Pb age and illite K-Ar age are in accord with the ages of the A-type granites and Sn mineralization in the southern Great Xing’an Range, at 140.58 ± 0.25 Ma, 136.3 ± 4.1 Ma and 130.0 ± 1.3 Ma respectively, which indicate the igneous and mineralization ages as being in the Early Cretaceous. This paper proposes that the post-collisional setting of the","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106527"},"PeriodicalIF":3.2,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The distinctiveness of carbonaceous debris in uranium reservoirs under arid sedimentary backgrounds and its implication for uranium mineralization: A case study of northern Ordos Basin","authors":"Weihui Zhong ,&nbsp;Liqun Wu ,&nbsp;Longhui Wang ,&nbsp;Yangquan Jiao ,&nbsp;Fan Zhang ,&nbsp;Liang Yue ,&nbsp;Yao Xiang ,&nbsp;Yuhang Zheng","doi":"10.1016/j.oregeorev.2025.106526","DOIUrl":"10.1016/j.oregeorev.2025.106526","url":null,"abstract":"<div><div>In the northern Ordos Basin, numerous studies have revealed close associations between carbonaceous debris (i.e., CD) and uranium mineralization in the Zhiluo Formation (i.e., J₂<em>z</em>), which is greatly influenced by the humid sedimentary backgrounds. However, recent exploration has shown that the reservoirs in the Lower Cretaceous under arid sedimentary backgrounds are also rich in uranium resources, but CD within them is scarce and shows significant differences. The present study investigates the macerals, maturity and mineral composition of CD in the Huanhe Formation (i.e., K₁<em>h</em>) by mainly using optical microscope, photometer, scanning electron microscopy and energy dispersive spectroscopy. The results show that CD in K₁<em>h</em> is composed of vitrinite (mainly telinite) and inertinite (mainly fusinite), with inertinite content (i.e., IC) ranging from 0 to 19.81 %. Its vitrinite reflectance (i.e., VR) ranges from 0.415 % to 0.987 %. The plant cell cavities and fissures inside the CD are rich in uranium minerals, pyrite, and various other minerals. Compared with CD in J₂<em>z</em> (IC = 0 to 12 %, VR = 0.258 % to 0.514 %), most CD in K₁<em>h</em> is of significantly higher IC and VR. The analysis reveals that 96 % of CD in J₂<em>z</em> (VR &lt; 0.5 %) originates from synsedimentary plant remains or peat debris and only 4 % (VR &gt; 0.5 %) originates from ancient strata. By contrast, CD in K₁<em>h</em> can be classified into two genetic categories: endogenous supply from the basin (VR &lt; 0.5 %) and exogenous supply from provenance (VR &gt; 0.5 %), with the latter accounting for 62.5 %. The former originates from coal debris of Middle Jurassic or synsedimentary plant remains. It can be subdivided into two subcategories according to diverse coal debris or varying degrees of modification by fire and oxidation: exhibiting low IC (&lt;12 %) and high IC (&gt;12 %) respectively. The latter originates from coal debris or old CD transported from the provenance. It can also be subdivided into two subcategories based on the IC of the parent rocks. Importantly, the CD, although rare, exhibits close associations with pyrite and uranium minerals, suggesting its significant role as the key enrichment agent for uranium precipitation under arid sedimentary backgrounds.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106526"},"PeriodicalIF":3.2,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revealing mineralization process of the Lehong carbonate-hosted Zn-Pb deposit: Insights from in-situ LA-ICP-MS analysis and fluid inclusion study of dolomite","authors":"Haobo Jia ,&nbsp;Dengfei Duan ,&nbsp;Junqin Wang ,&nbsp;Changqing Zhang ,&nbsp;Feng Sun ,&nbsp;Guowen Jiang ,&nbsp;Zhigang Kong ,&nbsp;Yue Wu","doi":"10.1016/j.oregeorev.2025.106530","DOIUrl":"10.1016/j.oregeorev.2025.106530","url":null,"abstract":"<div><div>Carbonate-hosted Zn-Pb deposits account for approximately 20% of global Zn-Pb resources. Understanding the fluid evolution and the source of metallogenic materials in these deposits is crucial for advancing exploration and the development of Pb and Zn resources. As a common gangue mineral in carbonate-hosted Zn-Pb deposits, dolomite is ideal for tracing the detailed evolution of ore-forming processes. While previous studies on fluid evolution in Zn-Pb deposits on carbonate minerals has been limited. The Lehong Zn-Pb deposit, a typical large-scale deposit in the Sichuan-Yunnan-Guizhou metallogenic belt, is characterized by a close association between dolomite and sulfides during the mineralization period, with distinct growth zoning under cathodoluminescence. Therefore, we selected the Lehong deposit as the focus of this study. This research employed in-situ LA-ICP-MS trace element analysis, fluid inclusion studies to investigate dolomite from different mineralization stages.</div><div>The paragenetic sequence of the Lehong deposit was divided into Pre-Ore, Ore, and Post-Ore stages, with an additional Cu mineralization event identified. Dolomite exhibited complex zoning patterns that reflect fluid-rock interactions, meteoric water input, replenishment of ore-forming fluid, and sulfide crystallization. Spatial analysis revealed a decreasing influence of ore-forming fluid and an increasing impact of meteoric water with distance from the massive ore zones. Temporally, the waning of ore-forming fluid and the increasing influx of meteoric water led to the development of low-temperature, low-salinity fluid (166.5 °C, 5.32 wt% NaCl equivalent) during the post-ore stage. Trace element data indicated that sulfide minerals deplete corresponding metals in dolomite, while Cu and Zn-Pb associated dolomite exhibit higher metal concentrations compared to barren ones. Additionally, we propose a mineralization process model for the Lehong deposit, which enhances the understanding of both its geology and mineralization processes. Overall, this study highlights the potential of using dolomite as a geochemical tracer to reconstruct fluid evolution and ore-forming processes in carbonate-hosted deposits, providing valuable insights for mineral exploration strategies.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106530"},"PeriodicalIF":3.2,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution of alkaline magmas and enrichment of rare earth elements: Insights from the geochemistry of apatite in the Saima alkaline igneous complex, Liaodong Peninsula, China","authors":"Rui-Xin Fu ,&nbsp;Ning-Bo Li ,&nbsp;He-Cai Niu ,&nbsp;Xu Zhao ,&nbsp;Yan Zhao ,&nbsp;Pan Qu","doi":"10.1016/j.oregeorev.2025.106524","DOIUrl":"10.1016/j.oregeorev.2025.106524","url":null,"abstract":"<div><div>Rare earth element (REE) mineralization related to alkaline magmas is an important source of REEs, and some deposits are enriched in heavy REEs (HREEs). However, the mechanisms of HREE enrichment in alkaline igneous rocks are unclear. In this study, we conducted petrographic, U–Pb geochronological, and <em>in situ</em> elemental and isotopic analyses of apatite in the Saima alkaline igneous complex, Liaodong Peninsula, China, the aim was to constrain the HREE geochemical behavior during alkaline magma evolution. The Saima complex consists of hornblende–pyroxene syenite, biotite syenite, syenite, nepheline syenite, and lujavrite (in order of magmatic evolution). Apatite U–Pb geochronology has yielded Late Triassic (hornblende–pyroxene syenite: 223 ± 5 Ma; biotite syenite: 220 ± 3 Ma; syenite: 219 ± 6 Ma; nepheline syenite: 219 ± 10 Ma) ages. Apatite in the hornblende–pyroxene syenite, biotite syenite, and syenite has similar geochemical compositions and textures, contains melt inclusions, and is classified as type Ⅰ apatite that formed in a purely magmatic system. Two types of apatite occur in the nepheline syenite. The type Ⅱ apatite has high Sr/Y and non-chondritic Y/Ho ratios, contains melt inclusions and scarce fluid inclusions, and is formed in a H₂O-saturated magmatic system. The type Ⅲ apatite is characterized by abundant fluid inclusions and has higher Sr contents, Th/U ratios, and ¹⁴⁷Sm/¹⁴⁴Nd ratios than the other apatite types. It has lower light REE (LREE) contents and higher HREE contents as compared with the type Ⅱ apatite and is formed by the reaction of type Ⅱ apatite with Cl-rich fluids. The calculated REE patterns of the equilibrium melt, based on <span><math><mrow><msubsup><mi>D</mi><mrow><mi>REE</mi></mrow><mrow><mi>apatite</mi><mo>-</mo><mi>m</mi><mi>e</mi><mi>l</mi><mi>t</mi></mrow></msubsup></mrow></math></span> values, are different from the corresponding whole-rock geochemical data. This finding, combined with the results of a Rayleigh fractionation model, indicates that a crystal mush accumulation model can explain the generation of the Saima complex. The enrichment of volatile components (e.g., H₂O) and crystal accumulation during the evolution of the magma mush were key controls on the anomalous HREE enrichment in the evolved rocks of the complex.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106524"},"PeriodicalIF":3.2,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143510669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Post-mineralization processes and preservation of porphyry deposits controlled by regional tectonic events: A comparative low-temperature thermochronology study of the Hadamiao and Bilihe porphyry Au deposits, north China","authors":"Tianyao Fu ,&nbsp;Wenbo Li ,&nbsp;Xueyuan Qiao ,&nbsp;Fanghua Zhang ,&nbsp;Xiuyuan Chen ,&nbsp;Baoxin Wang ,&nbsp;Martin Danišík","doi":"10.1016/j.oregeorev.2025.106529","DOIUrl":"10.1016/j.oregeorev.2025.106529","url":null,"abstract":"<div><div>Post-mineralization processes are closely linked to the preservation conditions of porphyry deposits and play an important role in resource prospecting. In this study, we investigate the genetically coeval (late Permian) and spatially adjacent Hadamiao medium-scale and Bilihe large-scale porphyry Au deposits in the Xing’ an-Mongolian Orogenic Belt using low-temperature thermochronology. Zircon (U-Th)/He (ZHe) and apatite fission track (AFT) dating were employed to constrain the denudation history of the mineralized intrusions. The Hadamiao deposit yielded ZHe ages of 237.3–207.8 Ma and AFT ages of 216.0–202.0 Ma. In contrast, the Hadamiao deposit exhibited ZHe ages of 154.9–134.6 Ma and AFT ages of 143.5–125.7 Ma. The narrow time intervals between ZHe and AFT results for both deposits suggest relatively rapid erosion. Inverse modelling indicates that the Bilihe deposit experienced weaker exhumation and greater sedimentary burial compared to Hadamiao. Absence of epithermal alteration in the Hadamiao deposit represents the erosion of the high-grade Au mineralization. Two distinct uplift/erosion events were identified from the thermochronological data and inverse modelling, likely correlating with regional tectonic episodes: (1) a Middle to Late Triassic event associated with continental collision following the closure of Paleo-Asian Ocean, and (2) a Late Jurassic to Early Cretaceoustriggered by flat slab subduction and subsequent rollback of Paleo-Pacific Ocean slab. Finally, we propose that the northern part of Bainaimiao Arc has high potential for deep prospecting based on the observed erosion and stratigraphic distribution.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106529"},"PeriodicalIF":3.2,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of gold endowment and exploration maturity in selected South African goldfields using Zipf’s law, deposit density regression, and the USGS three-part quantitative mineral resource assessment: Toward sustaining gold production","authors":"Litshedzani Mutele ,&nbsp;Emmanuel John M. Carranza","doi":"10.1016/j.oregeorev.2025.106513","DOIUrl":"10.1016/j.oregeorev.2025.106513","url":null,"abstract":"<div><div>South Africa hosts multiple Archean- to Proterozoic-aged goldfields, but its current gold production comes mainly from three terranes (i.e., Witwatersrand Goldfields, Amalia–Kraaipan Greenstone Belt and Barberton Greenstone Belt). A recent study indicated the potential depletion of reserves due to future production, lower resource-to-reserve conversion, and lack of exploration programs to delineate new resources. Aiming to encourage exploration activities and to sustain gold production, we assessed potential residual gold resource endowment, estimated the number of undiscovered gold deposits, and quantified exploration maturity within the selected goldfields using Zipf’s Law, the deposit density regression (DDR) technique, and the USGS three-part quantitative mineral resource assessment (3-part QMRA). Based on Zipf’s curve, the Sabie–Pilgrim’s Rest Goldfield (SPRG) is the most exploration-mature geologically-permissive tract (∼68 %) with residual ore tonnages of at least 8.29 Mt (in 11 deposits &gt; 0.50 Mt), followed by the Murchison (MGB) (∼45 %), Pietersburg (PGB) (∼45 %) and Amalia–Kraaipan Greenstone Belts (AKGB) (∼43 %) with residual ore tonnages of 2.17 Mt (in 3 deposits &gt; 0.60 Mt), 1.01 Mt (in 5 deposits &gt; 0.05 Mt) and 477 Mt (in 13 deposits &gt; 10 Mt), respectively. The DDR demonstrated that the AKGB and PGB have at least 1 undiscovered gold deposit at the 90th percentile but none for MGB and SPRG. The geologically-permissive tract for AKGB and PGB have a mean of at least 2 and 3 expected numbers (E(N)) of undiscovered gold deposits, respectively. The DDR also showed that the Sabie–Pilgrim’s Rest contains a median gold tonnage of 17.17 t (mean of 19.22 t), Murchison Greenstone Belt a median of 12.68 t (mean of 13.53 t), the Pietersburg Greenstone Belt a median of 0.16 t (mean of 2.06 t), and the Amalia–Kraaipan Greenstone Belt a median of 18.45 t (mean of 31.71 t). The USGS 3-part QMRA, only for SPRB and MGB, showed that these goldfields have at least 2 undiscovered deposits at the 90th percentile with mean ore tonnages of 0.79 Mt and 1.45 Mt, respectively. In these studied geologically-permissive tracts, the residual ore tonnages are likely an amalgamation of small- to medium-sized gold deposits, as the larger gold deposits have already been delineated. Most known gold deposits are also under-estimated compared to their expected gold endowment; hence, these estimated gold resources represent unexplored ore tonnages within known and undiscovered gold deposits. An effort is needed to delineate and develop the estimated undiscovered gold resources and increase the search spaces in all the studied geologically-permissive tracts.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106513"},"PeriodicalIF":3.2,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143510670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Knowledge graph construction with BERT-BiLSTM-IDCNN-CRF and graph algorithms for metallogenic pattern discovery: A case study of pegmatite-type lithium deposits in China","authors":"Xin Yang ,&nbsp;Li Sun ,&nbsp;Mei-Ling Liu ,&nbsp;Ke-Yan Xiao ,&nbsp;Cheng Li ,&nbsp;Xu-Chao Dong","doi":"10.1016/j.oregeorev.2025.106514","DOIUrl":"10.1016/j.oregeorev.2025.106514","url":null,"abstract":"<div><div>Compared to traditional geological data processing methods, knowledge graphs are more effective in calculating and processing the associated information and implicit geological knowledge within the data, helping to accurately grasp the underlying patterns and relationships of geological phenomena. To further optimize the semantic representation of geological text data and extract more detailed feature information, this study introduces the dilated convolutional neural network (IDCNN) layer into the Bert-BiLSTM-CRF model, constructing the Bert-BiLSTM-IDCNN-CRF framework for the precise extraction of lithium deposit named entities.This framework is then used to construct a knowledge graph for granite (pegmatite) lithium deposits in China. Experimental results demonstrate that the Bert-BiLSTM-IDCNN-CRF model exhibits excellent performance in processing Chinese geological text data, achieving a precision of 89%, a recall rate of 87%, and an F1 score of 88%. These results confirm the model's high effectiveness in geological named entity recognition and extraction tasks. Based on this, the study further employs centrality and similarity algorithms from graph theory to deeply analyze the metallogenic characteristics and potential patterns of lithium deposits. This analysis successfully identifies key influencing factors and core nodes for each lithium belt, providing a solid scientific foundation for subsequent lithium exploration target area delineation.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106514"},"PeriodicalIF":3.2,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143593865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}