Geoscience frontiers最新文献

{"title":"The Messinian halite facies: Insights into halite crystallisation and depositional environments using geochemical, petrographic and fluid inclusion studies","authors":"Mara Cipriani ,&nbsp;Alessandra Costanzo ,&nbsp;Martin Feely ,&nbsp;Adriano Guido ,&nbsp;Massimo D’Antonio ,&nbsp;Giovanni Vespasiano ,&nbsp;Sandro Donato ,&nbsp;Giuseppe Cianflone ,&nbsp;Giuseppe Maruca ,&nbsp;Carmine Apollaro ,&nbsp;Francesca Alessandro ,&nbsp;Francesco Perri ,&nbsp;Rocco Dominici","doi":"10.1016/j.gsf.2025.102207","DOIUrl":"10.1016/j.gsf.2025.102207","url":null,"abstract":"<div><div>The Crotone Basin (Calabria, Southern Italy) is a representative area in the Italian peninsula where Messinian halite deposits preserve three distinct crystal facies: (i) <em>banded</em> composed of cumulate halite and mud-rich interlayers, (ii) <em>white</em> consisting of bottom-growth crystals with chevron fabrics, and (iii) <em>transparent</em> made up of massive, optically pure crystals. The transparent facies appears to be undocumented in other Mediterranean Messinian basins, offering new perspective on halite crystallisation under variable environmental conditions. Microscopic observations (optical and scanning electron microscopy), supported by high-resolution 3D imaging through synchrotron-based X-ray microtomography, revealed a lack of pervasive recrystallisation in all facies, enabling the non-destructive visualisation of internal fabrics and inclusions. These methods provided critical insights into halite growth dynamics and the environmental conditions prevailing during deposition.</div><div>Microthermometric data indicated that all halite crystals precipitated from a NaCl-MgCl₂-H₂O salt-water system under extreme evaporative conditions, with fluid salinity exceeding 340 ‰ – 360 ‰ and a distinct brine temperature for each facies (∼35 °C in the banded, ∼45 °C in the white, and ∼ 20 °C in the transparent). Strontium isotope ratios (⁸⁷Sr/⁸⁶Sr) placed halite formation within the TG14-TG12 interval (ca. 5.61 – 5.55 Ma), with progressively increasing values from banded to transparent facies, suggesting enhanced continental input and brine dilution in the later stages of deposition.</div><div>Organic matter was detected both in primary fluid inclusions and within the halite lattice, particularly in the white and transparent facies. Raman spectroscopy and UV-epifluorescence revealed amorphous organic compounds, including carotenoids and aliphatic functional groups such as methyl and methylene, which are commonly associated with microbial activity. These findings suggested that organic-rich brines may have played an active role in crystal nucleation and growth dynamics. The chemical immaturity and heterogeneous distribution of organic compounds imply a combination of autochthonous microbial input and episodic allochthonous influx, pointing to complex organic-mineral interactions during halite formation.</div><div>The coexistence of three petrographically distinct halite facies within a confined area, each linked to specific environmental and geochemical conditions, supports the view that halite precipitation was modulated by fluctuations in hydrological balance, brine composition, and organic matter availability. These data contribute to a better understanding of the environmental and geochemical processes that controlled evaporite deposition during the Messinian Salinity Crisis.</div></div>","PeriodicalId":12711,"journal":{"name":"Geoscience frontiers","volume":"17 1","pages":"Article 102207"},"PeriodicalIF":8.9,"publicationDate":"2025-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145576765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 missing late Cretaceous magmatic arc in the Arabia-Eurasia collision zone (NW Iran): constraints from zircon geochronology, Hf isotopes, and geochemistry","authors":"Ali Mohammadi ,&nbsp;Hadi Shafaii Moghadam ,&nbsp;Amaneh Kaveh-Firouz ,&nbsp;Anna Lechmann ,&nbsp;Fulong Cai ,&nbsp;Lin Ding","doi":"10.1016/j.gsf.2025.102205","DOIUrl":"10.1016/j.gsf.2025.102205","url":null,"abstract":"<div><div>The Late Cretaceous magmatic evolution of northwestern (NW) Iran reveals a previously unrecognized continental arc system, the Azerbaijan Continental Magmatic Arc, herein termed the Azerbaijan Continental Magmatic Arc, which is largely obscured by subsequent tectonic overprinting, erosion, and basin burial. Integration of new zircon U-Pb ages, Lu-Hf isotopic data, and whole-rock geochemical compositions from volcanic and plutonic rocks in the Misho, Sufian, Moro, Amand, Vanyar, and Iskandar regions identifies a subduction-related arc system distinct from the Sanandaj–Sirjan and Urumieh–Dokhtar magmatic belts. The ∼ 101–97 Ma gabbros and granodiorites record <em>ε</em>_Hf(<em>t</em>) values from + 9.8 to −7.2, reflecting variable mantle and crustal inputs. Arc-like trace-element patterns, including LREE enrichment and subduction-related anomalies, together with structural alignments along the Siah Cheshmeh–Khoy–Misho–Tabriz Fault (SKMT), indicate arc magmatism contemporaneous with transpressional deformation. The magmatic series evolved from juvenile tholeiitic to enriched shoshonitic compositions, tracking increasing crustal assimilation and slab rollback. This flare-up event represents a transient phase of Neo-Tethyan subduction, later overprinted by Eocene intrusions of the Urumieh–Dokhtar Magmatic Arc. Collectively, these results highlight the cryptic preservation of continental arcs and propose that the SKMT Fault marks a concealed suture accommodating Late Cretaceous arc migration and back-arc basin development in NW Iran.</div></div>","PeriodicalId":12711,"journal":{"name":"Geoscience frontiers","volume":"17 1","pages":"Article 102205"},"PeriodicalIF":8.9,"publicationDate":"2025-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early–Middle Permian paleogeomorphic transformations in the northwestern Upper Yangtze region: Implications for the evolution of the eastern Paleo-Tethys oceans","authors":"Minglong Li ,&nbsp;Qiang Xu ,&nbsp;Xiucheng Tan ,&nbsp;Bing Luo ,&nbsp;Yuan Zhong ,&nbsp;Di Xiao ,&nbsp;Zhanfeng Qiao ,&nbsp;Wenjie Yang ,&nbsp;Qilong Yang ,&nbsp;Yu Cao","doi":"10.1016/j.gsf.2025.102204","DOIUrl":"10.1016/j.gsf.2025.102204","url":null,"abstract":"<div><div>Understanding how the multi-branches subduction of the Paleo-Tethyan Ocean controlled the intraplate tectono-sedimentary evolution of the South China Block (SCB) is fundamental to comprehending the mechanisms of ocean-continent transformation in cratonic basins and the formation of the Sichuan super-basin. This study investigated the Lower–Middle Permian successions (Liangshan, Chihsia, and Maokou formations) on the northwestern margin of the SCB, a critical area lies at the junction between the Songpan–Garzê and Qinling tectonic domains. These Permian successions are subdivided into four three-order sequences based on an isochronous stratigraphic framework that integrates various analyses of lithofacies, gamma-ray, stable isotopes, and zircon U-Pb ages. Lithofacies associations reveal that Lower-Middle Permian sequences record the sedimentary evolution process from shore–swamp environments to rimmed platforms. The paleogeomorphology pattern transitioned from a northwest lowland and southeast highland in the early Permian to a northeast lowland and southwest highland in the middle Permian, with corresponding development of linear high-energy grain shoals trending to northeast and northwest, respectively. These changes in lithofacies and paleogeography were attributed to the evolution of multiple branches of the Paleo-Tethyan, including the opening of the Garzê–Litang back-arc Ocean, along the western margin of the SCB in the Early Permian, followed by the rapid northward subduction of the Mianlue Ocean stretching along the northern margin of the SCB. Our findings demonstrate the regional cratonic tectono-sedimentary evolution coupled the multi-stage and multi-directional subduction of Paleo-Tethyan oceanic branches enhances our understanding of global deep-time multi-sphere interactions.</div></div>","PeriodicalId":12711,"journal":{"name":"Geoscience frontiers","volume":"17 1","pages":"Article 102204"},"PeriodicalIF":8.9,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145576766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An integrated geochemical and hydrological approach for the conceptualization of surface-water/groundwater interactions in a transboundary river basin of the western Himalayas","authors":"Tanveer Dar ,&nbsp;Nachiketa Rai ,&nbsp;Akhtar Jahan ,&nbsp;Mohd Aadil Bhat ,&nbsp;Sudhir Kumar","doi":"10.1016/j.gsf.2025.102203","DOIUrl":"10.1016/j.gsf.2025.102203","url":null,"abstract":"<div><div>Surface water–groundwater (SW–GW) interactions at the basin scale are critical for effective water resource management but remain poorly constrained in Himalayan river systems. This study integrates hydrogeochemical (major and trace elements), isotopic (²H, ³H, ¹⁸O), and hydrogeological data to investigate water origin, residence time, hydrochemical evolution, and SW–GW connectivity in the transboundary Upper Jhelum River Basin (UJRB), western Himalayas. Hydrogeochemical facies analysis reveals that recharge waters (RW) and shallow groundwater (SGW) are dominated by Ca²⁺–Mg²⁺–HCO₃⁻ facies, while deep groundwater (DGW) evolves towards Ca²⁺–Na⁺–HCO₃⁻ facies, reflecting prolonged water–rock interaction. Seasonal variability highlights the influence of aquifer residence time and localized anthropogenic inputs on water chemistry. SW–GW interactions are evident in the transition from Ca²⁺–Mg²⁺–HCO₃⁻ in tributary waters to mixed facies in groundwater, indicating active recharge and subsequent mineral dissolution. Mixing model results (<em>δ</em>¹⁸O and EC) show that groundwater is the dominant contributor to river baseflow, with contributions of 66 % ± 7 % in winter and 39 % ± 10 % in spring. River gaining conditions were identified along the alluvial and lacustrine plains, while localized losing stream conditions occurred near mountain front zones. Water–rock interactions, confirmed by Gibbs plots, govern basin hydrochemistry. Carbonate dissolution, gypsum dissolution, and silicate weathering are the primary processes, while Na-silicate weathering from the Panjal Traps shapes tributary chemistry. Ion exchange (Ca²⁺–Na⁺ and Mg²⁺–Na⁺ substitutions) further modifies groundwater composition along flow paths. Anthropogenic impacts, including wastewater infiltration and agricultural runoff, contribute to elevated Cl⁻, SO₄²⁻, and trace metal levels in specific zones. Evaporation effects are limited but elevate TDS locally. Glacier meltwater, characterized by Na⁺–Cl⁻–SO₄²⁻ facies, reflects atmospheric deposition and plays a minor hydrochemical role. These integrated findings underpin a conceptual flow model demonstrating how lithology, recharge dynamics, and anthropogenic pressures collectively shape SW–GW interactions. The results provide critical insights for managing transboundary Himalayan aquifers and sustaining river baseflows essential for regional water security.</div></div>","PeriodicalId":12711,"journal":{"name":"Geoscience frontiers","volume":"17 1","pages":"Article 102203"},"PeriodicalIF":8.9,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145576767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecological risk of selenium, cadmium, and arsenic in high-background sedimentary terranes: Insights from element enrichment and speciation in rocks","authors":"Minglong Li ,&nbsp;Hai-Bo Qin ,&nbsp;Yunfen Zhu ,&nbsp;Lan Yao ,&nbsp;Xunru Ai ,&nbsp;Liang Qiu ,&nbsp;Deshun Zheng","doi":"10.1016/j.gsf.2025.102191","DOIUrl":"10.1016/j.gsf.2025.102191","url":null,"abstract":"<div><div>The main geological factors causing high levels of heavy metals (HMs) in soils in areas with sedimentary rocks are the exposure of black rock series (BRS) and the development of karst. The combined relationships, background concentrations, and speciation of Se and HMs in clastic rocks, carbonate rocks, and BRS remain unclear, which restricts HM traceability and remediation in high background soils. This study focuses on Ediacaran to Jurassic sedimentary rocks in South China and determines the total concentrations of Se, Cu, Zn, Pb, Hg, Cd, Cr, As, Ni, and total organic carbon (TOC), as well as their speciation. The results indicate that the TOC in sedimentary rocks is significantly positively correlated with Se, Hg, Cd, Cr, and Ni, followed by Cu and As, but not Pb and Zn. Cluster analysis reveals that Se is strongly associated with Cd and As. Compared with those in the upper continental crust (UCC), the enrichment levels of elements in BRS are ordered Se &gt; Cd &gt; Hg &gt; As &gt; Cr &gt; Ni &gt; Cu &gt; Pb &gt; Zn. The mean concentrations of Se, Cd, Hg, and As in BRS are 957.8, 62.9, 28.4, and 8.5 times those in the UCC, respectively. These elements are also relatively enriched in carbonate rocks. A risk assessment based on speciation indicates that Cd, Se and As in BRS have the greatest ecological risks, as well as Cd and As in carbonate rocks. Active speciation of Hg in all three rock types is less than 0.1% of the soil risk screening, indicating low risk. Therefore, the elevated risks of Cd, Se, and As in high-background areas may fundamentally stem from parent rocks. With a limited budget, the immediate focus should be on remediating Cd, As, and Se in the BRS areas, while also stepping up monitoring of Cd and As in the karst zones.</div></div>","PeriodicalId":12711,"journal":{"name":"Geoscience frontiers","volume":"17 1","pages":"Article 102191"},"PeriodicalIF":8.9,"publicationDate":"2025-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lithospheric thickness controls the porphyry Cu mineralization: Evidence from neighboring arc volcanic rocks","authors":"Yin-Hong Wang,&nbsp;Jun Deng,&nbsp;Jia-Jun Liu,&nbsp;Fang-Fang Zhang,&nbsp;Jin-Gao Liu,&nbsp;Shan Ke,&nbsp;Kang Wang,&nbsp;Zhong-Yu Zhang","doi":"10.1016/j.gsf.2025.102189","DOIUrl":"10.1016/j.gsf.2025.102189","url":null,"abstract":"<div><div>It is widely considered that porphyry Cu deposits formed via oceanic slab subduction are closely associated with hydrous and oxidized arc magmas. Of note, two suites of neighboring (∼40 km apart) Carboniferous arc volcanic rocks in Northwest China show different extents of mineralization: volcanic rocks from the Dananhu arc (DNHA) host one of the most important porphyry Cu deposit belts in China, whereas those from the Yamansu arc (YMSA), adjacent to DNHA, are ore-barren. These arc volcanic rocks, thus, provide a precious opportunity to explore the main factor that controls the genetic links between coeval arc lavas and porphyry Cu mineralization. Here we report whole rock major and trace element compositions and Mg–Sr–Nd–Pb isotopic data, generating a comprehensive geochemical comparison for these two suites of volcanic rocks from basalt to dacite. The whole-rock geochemical analyses suggest that at a given SiO₂ content, the YMSA basalts show lower MgO, CaO, Fe₂O₃^T, and TiO₂ contents than the DNHA basalts. The DNHA volcanic rocks have higher Sr/Y and (La/Yb)_N ratios, which are positively correlated, indicating that these two suites of rocks were derived from different magma sources. The DNHA rocks are characterized by radiogenic Pb isotopic compositions with ²⁰⁶Pb/²⁰⁴Pb up to 19.457, clearly distinct from the YMSA volcanic rocks with less radiogenic Pb isotopic compositions (²⁰⁶Pb/²⁰⁴Pb = 18.146–18.487), suggesting variable assimilation of crust-derived components during magma evolution. The <em>δ</em>²⁶Mg values of the DNHA rocks (−0.35‰ to +0.06‰) are largely similar to those of the YMSA rocks (−0.24‰ to +0.04‰), and both sets of isotopic ratio ranges have tendency toward heavy Mg isotopes, which could be attributed to serpentinite-derived high-<em>δ</em>²⁶Mg fluids in their mantle sources. Both suites of arc lavas have constant Cu contents and Cu/Sc ratios, indicating inconspicuous pre-enrichment of Cu contents. Geochemical comparisons indicate that the DNHA rocks were derived from partial melting of peridotite at the depth around the spinel-garnet transitional stability field, whereas the YMSA rocks were derived from partial melting of spinel peridotite, and the DNHA magmas had a thicker overlying plate than that of the YMSA magmas. The thickened arc lithosphere facilitates water-rich magmas accumulation and garnet fractionation, driving the magmas to become more oxidized, thereby preventing sulfide segregation and releasing sulfide-bound Cu. Thus, magmas differentiation in the thickened arc lithosphere is a key factor influencing porphyry Cu ore potential.</div></div>","PeriodicalId":12711,"journal":{"name":"Geoscience frontiers","volume":"17 1","pages":"Article 102189"},"PeriodicalIF":8.9,"publicationDate":"2025-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145474586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Late Mesozoic porphyry copper deposits in NE China: Post-collisional versus subduction-related magmatic systems","authors":"Bizheng Yang ,&nbsp;Fanbo Meng ,&nbsp;Yuzhou Feng ,&nbsp;Xinran Ni ,&nbsp;Changzhou Deng ,&nbsp;Jingjing Zhu ,&nbsp;Runsheng Yin ,&nbsp;Huayong Chen","doi":"10.1016/j.gsf.2025.102190","DOIUrl":"10.1016/j.gsf.2025.102190","url":null,"abstract":"<div><div>Recent discoveries of Late Mesozoic porphyry Cu deposits (PCDs) in Northeast (NE) China reveal a distinct spatial metallogenic zonation, with Late Jurassic PCDs in the north dominated by Cu-Mo and Early Cretaceous PCDs in the east marked by Cu-Au mineralization. However, the mechanisms controlling this metallogenic contrast remain unclear. To tackle this issue, we combined geological, geochronological, and geochemical data to determine the genesis of these deposits and the key factors controlling their distinct Cu-Mo and Cu-Au mineralization. Geochronological data show that the Late Jurassic PCDs were formed during a short-lived mineralization event (ca. 150–147 Ma), in contrast to the Early Cretaceous PCDs, which exhibit a prolonged formation history (ca. 120–95 Ma). Geochemical data demonstrate that the northern Cu-Mo PCDs originate from partial melting of thickened juvenile lower crust, whereas the eastern Cu-Au PCDs result from oceanic crust-derived melts contaminated by mantle wedge materials. Integrated analysis suggests that the Cu-Mo PCDs formed in a post-collisional setting after the Mongol-Okhotsk Ocean closure, while the Cu-Au PCDs formed in a subduction setting associated with Paleo-Pacific oceanic plate subduction. Despite the presence of hydrous and oxidized magmas in both regions, the northern PCDs exhibit higher Sr/Y, La/Yb, and Sm/Yb ratios than the eastern PCDs, indicating greater magma differentiation depths controlled by crustal thickness. We therefore propose that the depths of magma differentiation govern the metallogenic zoning of Late Mesozoic PCDs in NE China.</div></div>","PeriodicalId":12711,"journal":{"name":"Geoscience frontiers","volume":"17 1","pages":"Article 102190"},"PeriodicalIF":8.9,"publicationDate":"2025-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145475009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-stage exhumation and preservation of the Mujicun porphyry Cu-Mo deposit, North China: A geo-thermochronological perspective","authors":"Fan Yang ,&nbsp;Jingwen Mao ,&nbsp;Gilby Jepson ,&nbsp;Fuquan Yang ,&nbsp;Leon Bagas ,&nbsp;Yingjie Li ,&nbsp;Zhenyu Qin","doi":"10.1016/j.gsf.2025.102184","DOIUrl":"10.1016/j.gsf.2025.102184","url":null,"abstract":"<div><div>Porphyry deposits are critical global sources of Cu, Mo, and Au. However, the mechanisms of post-mineralisation modification, exhumation, and preservation across different tectonic regimes remain poorly understood. The Mujicun deposit, a rare intracontinental porphyry Cu-Mo deposit in the North China Block, formed during the Early Cretaceous lithospheric thinning induced by the Paleo-Pacific slab rollback. Early studies focused predominantly on its genesis, the lack of research on post-mineralisation evolution has hindered regional prospecting. This study employs multiple geo-thermochronology, including zircon-apatite U-Pb and (U-Th)/He dating, as well as apatite fission-track analysis, combined with associated thermal history modelling, to elucidate the deposit’s temporal evolution, exhumation history, and preservation potential. Geochronological data indicate that dioritic magma emplacement and related Cu-Mo mineralisation at Mujicun occurred at ca. 146–141 Ma and ca. 145–138 Ma, respectively, coinciding with regional extension driven by Paleo-Pacific subduction. Integrated geo-thermochronological data and thermal history modelling reveal four tectono-thermal phases: (1) Late Cretaceous rapid cooling (ca. 110–95 Ma) and slow cooling during ca. 95–66 Ma, linked to lithospheric thinning of the eastern North China Block and the early uplift of the Taihang Mountains, triggered by Paleo-Pacific subduction and Okhotomorsk-Eurasia collision; (2) Late Cretaceous to Paleogene weak reheating (ca. 85–35 Ma), attributed to coeval sedimentary burial in the North Taihang Mountain and the nearby Bohai Basin; (3) Paleogene slow cooling (ca. 66–35 Ma), correlated with Pacific slab rollback and far-field effects from the India-Eurasia collision, inducing extensional uplift and exhumation of the Taihang Mountains; and (4) Neogene enhanced cooling (ca. 35–15 Ma), driven by Pacific subduction, India-Eurasia convergence, Tibetan Plateau extrusion, and the intensified East Asian monsoon, resulting in differential exhumation and planation of the Taihang Mountains. The Mujicun deposit shows exceptional preservation, as its total exhumation depth since ∼110 Ma (∼3.56 km) closely aligns with its original ore-forming depth (∼3.2–3.9 km). This indicates minimal post-mineralisation exhumation and limited erosional modification. Whereas current exploration targets shallow mineralisation (&lt;1.5 km), significantly deeper regional ore-forming depths (e.g., Dawan Mo deposit: 0.76–9.76 km) highlight the important potential for undiscovered Cu-Mo resources at depth within the North Taihang Mountain.</div></div>","PeriodicalId":12711,"journal":{"name":"Geoscience frontiers","volume":"17 1","pages":"Article 102184"},"PeriodicalIF":8.9,"publicationDate":"2025-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145474585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluid-silicate melt Cl partition and its implications on magmatic fluid exsolution and hydrothermal ore genesis","authors":"Jianping Li ,&nbsp;Xing Ding ,&nbsp;Huayong Chen","doi":"10.1016/j.gsf.2025.102187","DOIUrl":"10.1016/j.gsf.2025.102187","url":null,"abstract":"<div><div>Partition coefficients for Cl between felsic melts and a supercritical aqueous fluid (∼4–16 wt.% NaCl_eq) were experimentally determined to better constrain Cl behavior during magmatic fluid exsolution in upper-crustal magma chambers. Experiments were conducted at 850 °C, 200 MPa, and oxygen fugacity near NNO + 0.5, using a range of melt and fluid compositions. At constant total chlorinity of 1 mol/kg H₂O, <span><math><mrow><msubsup><mtext>D</mtext><mrow><mtext>Cl</mtext></mrow><mrow><mtext>fluid/melt</mtext></mrow></msubsup></mrow></math></span> values range from 11.3 to 21.1, negatively correlated with both the melt’s aluminum saturation index (ASI) and the HCl/total Cl ratio in the fluid. For a fixed melt composition (ASI = 1.02), <span><math><mrow><msubsup><mtext>D</mtext><mrow><mtext>Cl</mtext></mrow><mrow><mtext>fluid/melt</mtext></mrow></msubsup></mrow></math></span> values increase linearly from 18.7 to 60.1 as total chlorinity rises from 1 to 4 mol/kg H₂O. Rayleigh fractionation modeling of fluid exsolution from upper-crustal magmas using these data indicates that during progressive crystallization, chlorinity of exsolved fluids rapidly decline before stabilizing at ∼1 mol/kg H₂O (∼4 wt.% NaCl_eq), regardless of initial fluid chlorinity or H₂O content in melt. This implies that the majority of exsolution fluids released from felsic magmas in the upper crust are of low salinity (∼1 mol/kg H₂O). Copper transfer modeling further suggests that efficient metal extraction occurs in Cl- and H₂O-rich magmas, particularly where early H₂O saturation is achieved, thus favoring the formation of high-grade porphyry copper deposits.</div></div>","PeriodicalId":12711,"journal":{"name":"Geoscience frontiers","volume":"17 1","pages":"Article 102187"},"PeriodicalIF":8.9,"publicationDate":"2025-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145475008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crustal contamination and insights into diachronous changes toward modern tectonics: evidence from Hf-Nd-O-Pb isotope of sanukitoids from the Amazonian craton","authors":"Aline Costa do Nascimento ,&nbsp;Davis Carvalho de Oliveira ,&nbsp;Esa Heilimo ,&nbsp;Marco Antonio Galarza ,&nbsp;Eleilson Oliveira Gabriel ,&nbsp;Martin Whitehouse ,&nbsp;Matti Kurhila ,&nbsp;Cláudio Nery Lamarão","doi":"10.1016/j.gsf.2025.102172","DOIUrl":"10.1016/j.gsf.2025.102172","url":null,"abstract":"<div><div>Archean sanukitoids provide crucial insights into crust-mantle interactions during the early Earth’s geodynamic evolution. However, the role of crustal contamination in their genesis remains uncertain. Sanukitoids identified in the Sapucaia subdomain of the southern Carajás Province are represented by two plutons Água Limpa and Água Azul, collectively referred to as the Água Limpa sanukitoid suite. These plutons are compositionally similar to low-Ti sanukitoids (&lt; 0.63 % TiO₂) and their zircon isotopic data record a short period of magmatic activity around ca. 2.87 Ga. Sanukitoids zircons reveal <em>ε</em>_Hf(<em>t</em>) values ranging from –3.31 to + 2.14, Hf and Nd model ages between 2.91 Ga and 3.28 Ga, whole-rock <em>ε</em>_Nd(<em>t</em>) values from –1.64 to + 1.76, and <em>δ</em>¹⁸O values ranging from 5.0 ‰ to 7.6 ‰. The Pb isotopic compositions in K-feldspar (<em>µ</em> &gt; 10) suggests a Mesoarchean mantle source affected by slight crustal contribution and/or contamination. Result of geochemical modelling indicates that the sanukitoids were formed by ∼ 15 % partial melting of mantle peridotite previously enriched by ∼ 30 % of slab-derived melts, with orthopyroxene, garnet, clinopyroxene, phlogopite, and magnetite as residual phases. The integration of our data with previously published results leads us to suggest that modern-style plate tectonics may have initiated along the northern Carajás Province during the Mesoarchean, while the Rio Maria domain to the south remained dominated by mantle plume-driven crustal growth and vertical tectonics.</div></div>","PeriodicalId":12711,"journal":{"name":"Geoscience frontiers","volume":"16 6","pages":"Article 102172"},"PeriodicalIF":8.9,"publicationDate":"2025-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145358042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}