Acta Geochimica最新文献

{"title":"Extraction of niobium from the Bayan Obo Fe-REE-Nb deposit: A comprehensive review and new insights","authors":"Kaixuan Liu,&nbsp;Xing Ding,&nbsp;Haotian Liu,&nbsp;Xiaolong Huang","doi":"10.1007/s11631-025-00779-6","DOIUrl":"10.1007/s11631-025-00779-6","url":null,"abstract":"<div><p>With the development of aviation, superconducting, and other steel industries, the demand for niobium (Nb) has significantly increased worldwide, positioning it as a critical strategic metal. The Bayan Obo rare-earth elements (REE)-Nb-iron (Fe) deposit contains over 70% of China’s Nb resources and hosts the world’s largest reserves of REE. However, due to technical and environmental challenges, a substantial portion of the Nb resources remains underutilized and stored in tailings. Research and development of efficient, environmentally friendly, low-energy consumption, and less complex methods for extracting Nb from the Bayan Obo tailings possess significant scientific value and strategic importance. This paper reviews the current research status and distinctive geological and mineralogical characteristics of Nb resources in the Bayan Obo deposit, as well as existing pyrometallurgical and hydrometallurgical technologies for extracting Nb from ores and tailings, subsequently comparing their advantages to guide the development of new processes. Based on a comprehensive consideration of the technical, economic, environmental, quality, and safety aspects, it is suggested that future research should prioritize establishing a systematic recommendation procedure for targeted Nb-bearing mineral characterization and analysis for the Bayan Obo tailings, developing fluoride-free or low-fluoride hydrometallurgical techniques, and exploring innovative methods for Nb mineral coarsening. This review thus provides new insights into the efficient utilization of the Bayan Obo Nb resources and supports the development of innovative and effective strategies for optimizing Nb extraction from ores and tailings.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"44 on","pages":"1074 - 1100"},"PeriodicalIF":1.3,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145284363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extraction of deep mineralization information from weak and low tectono-geochemical anomalies: A case study of the Maoping germanium-rich lead–zinc deposit in northeastern Yunnan Province, China","authors":"Yixuan Yang,&nbsp;Gaoming Zhou,&nbsp;Runsheng Han,&nbsp;Hongsheng Gong,&nbsp;Jianbiao Wu,&nbsp;Yan Zhang,&nbsp;Yaya Mi","doi":"10.1007/s11631-025-00776-9","DOIUrl":"10.1007/s11631-025-00776-9","url":null,"abstract":"<div><p>Tectono-geochemical analysis is one of the key technical methods for deep prospecting and prediction, but the extraction of information on weak and low degrees of mineralization remains a significant challenge. This study takes the Maoping super-large germanium-rich lead–zinc deposit in northeastern Yunnan as an example, systematically analyzes the mineralization element assemblages and their anomaly distribution characteristics, extracts information on low and weak anomalies at depth, clarifies the spatial distribution of ore-forming element anomalies and fluid migration patterns, and establishes tectono-geochemical deep anomaly evaluation criteria and prospecting models, thereby proposing directions for deep prospecting in the deposit. This research shows that the mineralization element assemblage of the F1 factor (Cd-Cu-Ge-Zn-Sb-In-Pb-Sr(-)-As-Hg) anomalies represents near-ore halos; the element assemblage of the F2 factor (Ni-Co-Cr-Rb-Ga) anomalies represents tail halos; the element assemblage of the F3 factor (Rb-Mo-Tl-As) anomalies represents front halos; and the element assemblage of the F4 factor (Ba-Ga) anomalies represents barite alteration anomalies. Elements such as Zn and Pb exhibit significant anomalies near the lead–zinc ore bodies. In the study area, vertical anomalies in the eastern region of the Luoze River indicate that ore-forming fluids migrated from the SE at depth to the NW at shallower levels, whereas in the western region, ore-forming fluids migrated from the SW at depth to the NE at shallower levels. Thus, the lateral extensions of different ore bodies in the eastern and western regions of the river have been determined. On this basis, tectono-geochemical deep anomaly evaluation criteria for the deposit are established, and directions for deep prospecting are proposed. This study provides scientific value and practical significance for deep prospecting and exploration engineering planning for similar lead–zinc deposits.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"44 6","pages":"1254 - 1275"},"PeriodicalIF":1.3,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145646334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Arsenopyrite reveals the deuteric origin of the Saxi tungsten deposit, SW China","authors":"Wanbo Li,&nbsp;Mingguo Deng,&nbsp;Qiang Weng,&nbsp;Wenchang Li,&nbsp;Zhen Jia,&nbsp;Wenbo Song,&nbsp;Zhengrong Li,&nbsp;Jiafei Yang","doi":"10.1007/s11631-025-00777-8","DOIUrl":"10.1007/s11631-025-00777-8","url":null,"abstract":"<div><p>The Saxi tungsten deposit, located in the Laojunshan ore district of southeastern Yunnan Province, is a significant W-polymetallic deposit. The origins of tungsten-bearing pegmatite dikes and quartz vein mineralization in the Saxi deposit remain poorly understood. This study employs in situ U–Pb dating of apatite from the altered granite, along with trace element and S–Pb isotopic analysis of arsenopyrite, to investigate the timing, source of ore-forming fluids and the mechanisms of tungsten enrichment. The apatite in the altered granite yields a U–Pb age of 147.0±4.0 Ma, indicating magmatic activity during the Early Cretaceous. Three generations of arsenopyrite (Apy) are identified: Apy-1 in the altered granite, Apy-2 in the pegmatite dikes and Apy-3 in the quartz veins. The S/Fe ratios for Apy-1, Apy-2 and Apy-3 range from 0.98 to 1.09, 0.89 to 0.92 and 0.86 to 1.02, respectively (average 0.97), suggesting a magmatic-hydrothermal origin. Sulfur isotope values (<i>δ</i>³⁴S = 4.29‰–8.11‰) indicate that it was likely sourced from deep magmatic-hydrothermal fluids. Lead isotopic compositions of arsenopyrite suggest that the granitic parental magma is derived from the upper crust. These findings point to a magmatic-hydrothermal origin for the vein-type tungsten mineralization, linked to a concealed magmatic-hydrothermal system in the Early Cretaceous.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"44 6","pages":"1276 - 1292"},"PeriodicalIF":1.3,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145646358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralogical and geochemical features of Sirginil phyllite group from Penjween area, Iraqi Kurdistan region: Implications for provenance and source-area weathering","authors":"Tola A. Mirza,&nbsp;Stavros P. Kalaitzidis,&nbsp;Shahra O. Abdalla,&nbsp;Sofia Tsiotou","doi":"10.1007/s11631-025-00778-7","DOIUrl":"10.1007/s11631-025-00778-7","url":null,"abstract":"<div><p>The Sirginil Phyllite Group being outcropping in Penjween area is investigated to determine the provenance and weathering level of the source area. Petrographic investigation of the phyllites shows that they are almost homogeneous in composition and highly crenulated. The most prominent features are kink band structures and network fabrics, consisting mainly of fine-grained mineral assemblages of chlorite, muscovite, quartz, and plagioclase feldspar. The geochemical data indicate that the phyllite rocks represent precursors of shales and greywackes as their protolith, having undergone an intensive degree of chemical weathering without sorting. Additionally, the presence of graphite, as an indication of organic matter, points to quick transport and burial of the protolith sedimentary rocks, which originated from a unique source area. The average values of the chemical alteration index and chemical weathering index indicate that a high degree of weathering of the source materials occurred in a humid environment. The Th/U ratio, as well as the concentrations of Th and U, indicates a sedimentary origin and oxidizing conditions during sedimentation of the protolith rocks. The REE pattern coupled with prominent negative Eu anomaly and low Th/Sc ratios, as well as the plots of La/Sc versus Th/Sc, La/Yb versus La/Ce, and Th/Yb versus Ta/Yb, indicates a continental margin as the paleoenvironment of the sedimentary protolith. The Th/Sc ratios for the studied samples denote origin from a predominantly felsic igneous source, while the median Zr/Sc ratio indicates only a minor degree of sorting and zircon addition in all the studied samples.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"45 2","pages":"384 - 401"},"PeriodicalIF":1.3,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147734891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sources and environmental risks of cadmium in soils affected by high geochemical background and artisanal zinc smelting activities","authors":"Chao Luo,&nbsp;Wangwang Zhou,&nbsp;Yizhang Liu,&nbsp;Jian Long,&nbsp;Zengping Ning,&nbsp;Chengshuai Liu","doi":"10.1007/s11631-025-00775-w","DOIUrl":"10.1007/s11631-025-00775-w","url":null,"abstract":"<div><p>Soil cadmium (Cd) pollution is a global environmental issue of significant concern. In southwestern China, soil Cd content is notably influenced by high geochemical background and mining/smelting activities. However, the specific contributions of these Cd sources to Cd enrichment and environmental risks in soils remain poorly understood. Therefore, this study investigated the total and bioavailable Cd and other metals in the topsoil and subsoils surrounding Caohai Lake in northwestern Guizhou Province. This research aimed to identify Cd sources, assess pollution characteristics, and evaluate the potential environmental risks. The results revealed that the carbonate bedrock has average Cd content of 0.66 mg/kg, confirming a naturally high geochemical background of Cd in the study area. Soil Cd content ranged from 0.14 to 6.69 mg/kg, with topsoil exhibiting higher average Cd content (2.29 mg/kg) than subsoil (0.71 mg/kg). Statistical analyses indicated that Cd in subsoil is primarily of geogenic origin. In contrast, approximately 87% of the total Cd in topsoil originates from atmospheric deposition linked to historical artisanal zinc smelting activities. The study found that Cd in topsoil reaches a moderate pollution level and poses a high potential ecological risk. Furthermore, the proportion of bioavailable Cd (DTPA-extractable) was significantly higher in topsoil (26%) than in subsoil (13%). This elevated Cd bioavailability in topsoil is attributed to atmospheric Cd deposition, lower soil pH, and higher organic matter content. These findings provide critical insights for managing Cd risks in soils from regions with high geochemical backgrounds and smelting activities.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"45 2","pages":"242 - 255"},"PeriodicalIF":1.3,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11631-025-00775-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147734897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 Suizhou meteorite: A treasure trove of high-pressure minerals","authors":"Xiande Xie,&nbsp;Luca Bindi,&nbsp;Ming Chen,&nbsp;Xiangping Gu","doi":"10.1007/s11631-025-00774-x","DOIUrl":"10.1007/s11631-025-00774-x","url":null,"abstract":"<div><p>The Suizhou meteorite is a heavily shock-metamorphosed L6 chondrite which contains thin shock melt veins. So far, 26 high-pressure phases have been identified from the meteorite. Among the high-pressure phases, ten of them were approved as new minerals which include tuite, xieite, wangdaodeite, chenmingite, hemleyite, poirierite, asimowite, hiroseite, elgoresyite, and ohtaniite, by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association. Other high-pressure phases identified from the meteorite are ahrensite, akimotoite, bridgmanite, lingunite, magnesiowüstite, majorite, majorite–pyrope_ss, maskelynite, riesite, ringwoodite, wadsleyite, and 5 other phases including phase A, vitrified phase B and phase C, phase D (Ca-rich majorite), and partly inverted ringwoodite. The occurrence and abundance of high-pressure phases makes this meteorite the one with the richest variety of high-pressure minerals to date.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"44 on","pages":"1059 - 1073"},"PeriodicalIF":1.3,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145284392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrographic and geochemical perspectives on sandstones of the extra-peninsular Gondwana Group from the Arunachal Himalayas, NE India: Probing provenance, tectonic context and paleoenvironmental conditions","authors":"Yadav Krishna Gogoi,&nbsp;Pradip Borgohain,&nbsp;Diganta Bhuyan,&nbsp;Devojit Bezbaruah,&nbsp;Garima Konwar,&nbsp;Manash Pratim Gogoi,&nbsp;Bubul Bharali","doi":"10.1007/s11631-025-00771-0","DOIUrl":"10.1007/s11631-025-00771-0","url":null,"abstract":"<div><p>The extra-peninsular Gondwana Group rocks are exposed in narrow patches within the Lesser Himalayan sequence of the NE-Arunachal Himalayas, India. The bulk of sediments for the sandstones of the Gondwana Group were derived from felsic/acidic to intermediate igneous rocks, with minor mafic input from the upper continental crust (UCC), as supported by various discrimination diagrams based on quantification of detrital minerals coupled with sandstone geochemistry. The inputs from metamorphic sources in subordinate amounts cannot be ruled out, as indicated by quantification of the quartz varieties. These sediments were found to be sourced from the interior part of a craton or shield and recycled platformal sediments which were derived from both passive and active margin settings. The sediments experienced a wide variance in climatic conditions, from arid to humid, suffering low–moderate-intensity weathering (CIA: 63.43; CIW: 86.18; WIP: 44.84; PIA: 75.37; ICV: 2.39; <i>C</i>-value: 0.42; PF: 0.49; Sr/Cu: 9.23 and Rb/Sr: 1.68) within the vicinity of the low plains to moderate hills. Additionally, redox-sensitive elements indicate the deposition of sediments under oxygenated or oxygen-rich conditions (U_au: −2.91; Th/U: 7.37; U/Th: 0.18; V/Cr: 1.71; δU: 0.67 and Ce/Ce*: 0.93).</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"44 4","pages":"880 - 911"},"PeriodicalIF":1.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145160471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The zoning rule and forming mechanism of tectonite-mineralized alteration lithofacies of black/fracture zone of the Daliangzi Pb–Zn deposit in southwest Sichuan in China","authors":"Lingjie Li,&nbsp;Runsheng Han,&nbsp;Jianbiao Wu,&nbsp;Zhixing Feng","doi":"10.1007/s11631-025-00773-y","DOIUrl":"10.1007/s11631-025-00773-y","url":null,"abstract":"<div><p>As one of the typical deposits in the Sichuan-Yunnan-Guizhou Pb–Zn metallogenic province, the Daliangzi Pb–Zn deposit has a close genetic relationship with the structural system of the black/fracture zone formed under the action of the NWW-approximately EW strike-slip structures in the metallogenic province. The R1 black/fracture zone has a close relationship with ore forming; however, the mechanism of the rock- and ore-controlling action of the structural system remains unclear. Based on a detailed analysis of the tectonite-mineralized alteration lithofacies of the R1 black/fracture zone, the tectonite-mineralized alteration lithofacies zones can be divided into four types in succession outward from the Pb–Zn mineralization center (F₅, F₁₀₀, and other faults), i.e., (1) the brecciated and stockwork-like Pb–Zn mineralization-complex breccia facies zone; (2) the stockwork-like Pb–Zn mineralization-simple breccia and cataclasite facies zone; (3) the veined pyrite–sulfide–dolomitic cataclasite facies zone; (4) the fine-veined calcite-black carbonized dolomite facies zone. With the evolution of the ore-forming fluid, the homogenization temperature decreases from Zone 1 to Zone 4; the salinity increases from Zone 1 to Zone 2 and then it decreases from Zones 3 and 4. The fluid density shows little change overall. The contents of Zn, Pb, Cu, Ga, Ge, Cd, Ag, and other metallogenic elements, Zn/Pb ratio, and CaO/MgO mole ratio decrease gradually from Zone 1 to Zone 4, and the REE fractionation, calcilization, silicification, and pyritization enhance gradually from Zone 1 to Zone 4. This series of changes is the product of diapirism (cryptoexplosion) of strike-slip structures and the black/fracture zone, among which the second-order structures derived from NWW-approximately EW-striking dextral shear-tension faults F₁ and F₁₅ control the brecciated and stockwork-like Pb–Zn mineralized complex breccia facies zones and the stockwork-like Pb–Zn mineralized simple breccia and cataclasite facies zones. Therefore, this paper establishes the zoning mode of tectonite-mineralized alteration lithofacies of the black/fracture zone and proposes that Zones 1 and 2 provide important prospecting criteria.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"44 6","pages":"1234 - 1253"},"PeriodicalIF":1.3,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145646123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrogenesis and geodynamic setting of the Wutang granites in the Tong’an-Baishuidong lithium mining district, South China: Evidence from monazite U–Pb chronology, geochemistry, and Nd–Pb isotope","authors":"Fushen Zhang,&nbsp;Xiaotian Zhang,&nbsp;Fangrong Zhang,&nbsp;Yong Zhang,&nbsp;Zhe Xu,&nbsp;Xinyu Xu,&nbsp;Jiayong Pan,&nbsp;Fei Xia,&nbsp;Guoqi Liu,&nbsp;Yu Zhou,&nbsp;Ying Liu,&nbsp;Longmin Nie,&nbsp;Fujun Zhong","doi":"10.1007/s11631-025-00772-z","DOIUrl":"10.1007/s11631-025-00772-z","url":null,"abstract":"<div><p>The Tong’an-Baishuidong mining district (TBMD), located in the eastern section of the Jiangnan Orogen, is a newly discovered granite-type lithium mining district. Thisstudy presents new monazite U–Pb chronological, whole-rock geochemical, and Nd–Pb isotopic data to reveal the petrogenesis and geodynamic setting of the Wutang granites in the TBMD. The monazite U–Pb age of 145.8 ± 1.0 Ma indicates that the granites were emplaced at the end of the Late Jurassic. Whole-rock geochemical results demonstrate that the Wutang granites are enriched in SiO₂ (72.80–73.40 wt%) but depleted in CaO (0.44–0.90 wt%) and MgO+TiO₂+TFeO (1.79–2.05 wt%). These granites exhibit negative Eu anomalies (<i>δ</i>Eu = 0.3−0.4) and high aluminum saturation indexes (A/CNK = 1.2−1.6), differentiation indexes (DI = 90–92), and Rb/Sr ratios (4.7–8.1). They also have moderate Ba contents (239–278 ppm) and low Sr contents (52.7–82.0 ppm) as well as low Nb/Ta (2.2–5.3) and Zr/Hf (21.3–31.5) ratios. All these indicate that they are highly fractionated granites. Additionally, these granites contain 5–10 wt% muscovite but no hornblende, with calculated corundum contents of 2.3–5.5 wt%. They have low high-field strength element (HFSE) contents (Zr + Nb + Ce + Y = 182–202 ppm) and zircon saturation temperatures (700–770 °C), with Th and Y negatively linked with Rb. These petrographic and geochemical features further reveal that the Wutang granites belong to highly fractionated S-type granites. The ε_Nd(t) values of these granites range from −9.03 to −8.23, corresponding to two-stage model ages (T_DM2) of 1488–1553 Ma. The initial Pb isotope ratios are: (²⁰⁶Pb/²⁰⁴Pb)_i = 18.38–18.55, (²⁰⁷Pb/²⁰⁴Pb)_i = 15.67–15.68, and (²⁰⁸Pb/²⁰⁴Pb)_i = 38.62–38.67. These Nd–Pb isotopic results demonstrate that the parental magma originated from the partial melting of ancient crustal materials. In the meantime, the TBMD in the eastern section of the Jiangnan Orogen was in a compression-extension transitional setting associated with the episodic subduction of the Paleo-Pacific Plate.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"44 4","pages":"912 - 930"},"PeriodicalIF":1.3,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145170348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The dynamic of major ions and dissolved inorganic carbon in urban rivers in Tianjin, North China","authors":"Min Xiao,&nbsp;Lili Li,&nbsp;Yuanbi Yi,&nbsp;Wenxi Zhang,&nbsp;Fujun Yue","doi":"10.1007/s11631-025-00768-9","DOIUrl":"10.1007/s11631-025-00768-9","url":null,"abstract":"<div><p>The distribution of diverse lithology and human activities impacts the water chemistry and carbon biogeochemistry of river systems. Major ion chemistry and dissolved inorganic carbon (DIC) in the urban rivers at Tianjin City, China, were examined based on a temporal and spatial sampling scheme in 2021. The concentrations of major ions exhibited significant spatial variations, showing agricultural input in the upstream and urban pollution in the downstream. The isotopic composition (<i>δ</i>¹³C) of DIC in the rivers ranges from −12.39‰ to −0.45‰, indicating partial equilibrium between the water and the atmosphere in some waters due to long residence time, where <i>δ</i>¹³C is typically 0‰. The waters with more negative <i>δ</i>¹³C values showed that biological CO₂ was a major contributor to DIC in most rivers. It experienced slightly more depletion during the wet season than in the dry season, reflecting strong degradation of organic matter in summer. The seasonal variations likely reflected changes in metabolic processes in the river in addition to alterations in the hydrological regime, highlighting the implications of freshwater given geoscientific, ecological, and environmental aspects. Essential aspects of human activities, including agriculture, urban development, and dam construction, significantly influence the dynamics of water chemistry and DIC. The study highlighted that variations in lithology and hydrology significantly affect the spatial and temporal changes in water chemistry and carbon geochemistry within river systems.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"45 2","pages":"217 - 229"},"PeriodicalIF":1.3,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147735039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}