Lithos最新文献

{"title":"Crustal-scale structural and compositional distinction beneath NE Tibet: Evidence from reflection-seismology and Vp/Vs imaging","authors":"Huilin Li ,&nbsp;Xiaoyu Guo ,&nbsp;Zhuo Ye ,&nbsp;Xingfu Huang ,&nbsp;Hongda Liang ,&nbsp;Xiaofan Deng ,&nbsp;Xiaomiao Tan ,&nbsp;Rui Gao","doi":"10.1016/j.lithos.2025.108032","DOIUrl":"10.1016/j.lithos.2025.108032","url":null,"abstract":"<div><div>Knowledge of the crustal structures and rock compositions of the Tibetan Plateau is key to understanding its growth and deformation. We utilized a ∼ 400 km multi-data seismic profile in NE Tibet that was constructed using deep seismic reflection data and a dense broadband array. The seismic reflection and Vp/Vs characteristics point to the existence of a crustal-scale structural and compositional boundary that corresponds to the Hezuo–Tanchang Fault in the West Qinling Orogen. South of the fault there is a decoupling of the upper and middle–lower crust. The upper crust is characterized by thrust structures and relatively low Vp/Vs ratios (&lt;1.70), typical of felsic quartz-rich rocks, while the middle crust exhibits anomalously high Vp/Vs ratios (1.8–2.0) and multiple north-dipping thrust–nappe structures that indicate regional mylonitization. Relatively transparent reflections with Vp/Vs ratios of ∼1.82 in the lower crust refer to the mafic rocks, likely composed of anorthosite/metagabbro resulting from the underplating from mantle-derived magmas. North of the fault, the entire crust exhibits weak reflections associated with the crust-cutting West Qinling Fault, with low Vp/Vs ratios (&lt;1.70) related to felsic rocks. The structural distinction is probably due to the differentiation in rock compositions that resulted from the Triassic amalgamation of the Songpan–Ganze Block and the Qilian Orogen. Cenozoic reactivation due to the northward movement of the Indian Plate produced different structures on either side of the West Qinling Orogen. The structural and compositional boundary would have constrained the northward growth of the plateau from central Tibet and resulted in a differential uplift of NE Tibet.</div></div>","PeriodicalId":18070,"journal":{"name":"Lithos","volume":"504 ","pages":"Article 108032"},"PeriodicalIF":2.9,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143592834","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":"Miocene high-grade metamorphism of the metapelites in the Cona region, eastern Himalaya, and tectonic implications for Himalayan orogeny","authors":"Khizar Hayat ,&nbsp;Laixi Tong ,&nbsp;Xiaohan Liu ,&nbsp;Christopher J.L. Wilson ,&nbsp;Zhao Liu ,&nbsp;Chao Li","doi":"10.1016/j.lithos.2025.108038","DOIUrl":"10.1016/j.lithos.2025.108038","url":null,"abstract":"<div><div>Metamorphic thermobaric ratios are used to interpret the evolution of convergent plate margins and to understand the evolution of the Higher Himalayan Crystalline Sequence. To better understand changes in pressure (P) and temperature (T) with time (t), we examine the metamorphic petrology, mineral chemistry, phase equilibrium modeling, and geochronology of the metapelites from the Cona area in the eastern Himalayan orogen. Based on this integrated approach, three metapelites were selected to study the Miocene metamorphism. Our results reveal that the metapelites preserve a peak garnet-kyanite-K-feldspar-bearing high-grade metamorphic mineral assemblage, and a post-peak sillimanite-bearing assemblage, and underwent the granulite-facies metamorphism and associated partial melting under P-T conditions of ca. 10 kbar and 725–775 °C, followed by isothermal decompression and isobaric cooling. Zircon dating indicates that these rocks experienced metamorphism between 24 and 14 Ma, accompanied by an increase in geothermal gradients from 21 °C/km (780 °C/GPa) to 29 °C/km (1190 °C/GPa), and finally to 32 °C/km (1250 °C/GPa). Thus, there is an increase in the thermobaric ratio and geothermal gradient along the north-south transect, concurrent with a decrease in elevation and age. We argue that these extreme gradients are a consequence of the active tectonic processes and ongoing deep crustal magmatism in the eastern Himalaya, whereas the decreasing trend of P-T conditions of peak metamorphism and younging of exhumation ages southward from the upper to lower Higher Himalayan Crystalline Sequence is well matched with a critical taper model.</div></div>","PeriodicalId":18070,"journal":{"name":"Lithos","volume":"504 ","pages":"Article 108038"},"PeriodicalIF":2.9,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143594020","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":"Evolution history of the northeastern North China Craton: Implications for the magma sources of Changbaishan and Longgang volcanoes","authors":"Feixiang Wei ,&nbsp;Lin Wang ,&nbsp;Guangpei Zhong ,&nbsp;Feng Guo ,&nbsp;Bo Pan ,&nbsp;Jiandong Xu","doi":"10.1016/j.lithos.2025.108034","DOIUrl":"10.1016/j.lithos.2025.108034","url":null,"abstract":"<div><div>To better understand the magma sources of Changbaishan and Longgang volcanoes in northeastern China, we investigated the metasomatism and melting history of the northeastern North China Craton (NCC). Our study includes whole-rock major and trace elements, platinum group element (PGE), and <em>Re</em><img>Os isotopic analyses of peridotite xenoliths entrained in Cenozoic volcanic rocks from the Changbaishan and Longgang volcanic fields. The peridotites are predominantly lherzolites with a small proportion of harzburgite, showing variable <span><math><msub><mi>Al</mi><mn>2</mn></msub><msub><mi>O</mi><mn>3</mn></msub></math></span> contents (0.41–3.77 wt%). The more depleted samples <span><math><mo>(</mo><msub><mi>Al</mi><mn>2</mn></msub><msub><mi>O</mi><mn>3</mn></msub></math></span> &lt; 2 wt% &amp; CaO &lt; 2 wt%) yield a <em>Re</em>-depleted model age (T_<em>RD</em>) of approximately 1.80 Ga, consistent with other parts of the NCC. The peridotites exhibit increasing PGE patterns, with pronounced enrichment of Pd. The Pd enrichment in the peridotites is linked to subduction-derived materials, indicating that Pd was likely enriched through rock-melt reactions during metasomatism. Based on the tectonic setting, we propose that following the cratonization of the northeastern NCC, the lithospheric mantle remained stable and refractory for a long period until metasomatism caused by silicate melts released during ancient subductions. Additionally, these xenoliths show significant depletion in Re, Cu, and S, suggesting that after refertilization, the lithospheric mantle underwent recent low-degree partial melting. Therefore, we suggest that the magma sources for the Changbaishan and Longgang volcanic fields comprise a mixture of EM I (derived from the mantle transition zone), DMM (asthenospheric mantle), and minor EM II (lithospheric mantle).</div></div>","PeriodicalId":18070,"journal":{"name":"Lithos","volume":"504 ","pages":"Article 108034"},"PeriodicalIF":2.9,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143594021","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":"CaREE-fluorcarbonates: A variety of morphologies, compositions and nanostructures with insights into REE partitioning and mobility","authors":"Roberto Conconi ,&nbsp;Paolo Gentile ,&nbsp;Patrizia Fumagalli ,&nbsp;Fernando Nieto ,&nbsp;Giancarlo Capitani","doi":"10.1016/j.lithos.2025.108033","DOIUrl":"10.1016/j.lithos.2025.108033","url":null,"abstract":"<div><div>A variety of CaREE-fluorcarbonates with differing morphologies and compositions have been studied: i) synchysite-(Ce) forming hexagonal prisms and rosette-like aggregates; ii) bastnäsite-(Ce) forming blocky aggregates; iii) bastnäsite-(Nd) forming desert rose-like intergrowths and iv) combinations of synchysite-(Ce) and bastnäsite-(Nd) forming more complex micro and nanostructures. These minerals are retained to form from a hydrothermal fluid in a temperature range between 350 and 100 °C. After an investigation spanning from the microscale to the atomic scale, which employed optical stereomicroscopy, scanning and transmission electron microscopy, microanalysis and Raman spectroscopy, a possible scenario for their formation has been depicted. It is assumed that the different CaREE-fluorcarbonates crystallized sequentially under decreasing temperature and fluid fractionation, with synchysite-(Ce) forming first, followed by bastnäsite-(Ce) and finally bastnäsite-(Nd). The different morphologies, in this case, besides being influenced by the dominant REE in the fluid, were also due to varying temperatures and cooling rates.</div><div>Our study highlights that nature may efficiently fractionate REE from one another, like Y from La, Ce and Nd; Ce from Nd and La. Additionally, Th, a radioactive and toxic element, seems to enter the structure of CaREE-fluorcarbonates during the final stages of crystallization. The understanding of these natural processes may suggest routes for improving current metallurgical separation processes.</div></div>","PeriodicalId":18070,"journal":{"name":"Lithos","volume":"504 ","pages":"Article 108033"},"PeriodicalIF":2.9,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580073","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":"Anatexis at different crustal levels in the Eastern Himalayan Syntaxis: Implications for crustal exhumation and uplift","authors":"Chenghua Liang ,&nbsp;Hongfei Zhang ,&nbsp;Biji Luo ,&nbsp;Nigel Harris ,&nbsp;Liang Guo","doi":"10.1016/j.lithos.2025.108026","DOIUrl":"10.1016/j.lithos.2025.108026","url":null,"abstract":"<div><div>An integrated study of zircon U<img>Pb dating and Hf isotopes, and whole-rock major and trace element analyses was conducted on Zhibai, Pai, and Duoxiongla formation leucosomes and leucogranites from the Namche Barwa, Eastern Himalayan Syntaxis, to constrain crustal anatexis across granulite-amphibolite transitions and its linkage to orogenic dynamics. Anatectic samples exhibit systematic variations in age clusters, mineral assemblages, and geochemical characteristics. Two anatectic episodes are identified: Late Oligocene-Early Miocene (∼23–17 Ma) and Late Miocene (∼10–5 Ma). The ∼23–17 Ma anatectic samples from the Zhibai and Pai formations, composed of peritectic K-feldspar, pyroxene, and garnet, show high FeO^T + MgO contents, lower Al₂O₃ and Na₂O contents, negative Eu anomalies (Eu/Eu* = 0.02 to 0.32), and negative ε_Hf(t) values of −23.8 to −1.53, with abundant inherited zircons (ε_Hf(t) = −18.9 to +9.7), indicating that they could form by dehydration-melting of metagreywackes. Some ∼23–21 Ma and ∼ 10 Ma samples from the Zhibai formation are fine-grained quartz and plagioclase with minor clinopyroxene and hornblende. They show high Al₂O₃, Na₂O, CaO, low FeO^T + MgO and K₂O/Na₂O values, without cumulate textures. These 23–21 Ma samples show negative ε_Hf(t) values (−19.8 to −0.6) with T_DM2(Hf) of 2.4–1.1 Ga, consistent with formation from hydrous-melting of old heterogeneous basement rocks. In contrast, the 10 Ma samples show positive Eu anomalies (Eu/Eu* = 1.21) and ε_Hf(t) values of +10.9 ∼ +16.7, suggesting that they were derived from hydrous-melting of juvenile crustal rocks. The Pai and Duoxiongla formation's samples (∼10–5 Ma) have plagioclase and hornblende, with high Na₂O, flat to weakly negative Eu anomalies (Eu/Eu* = 0.49–0.87), and negative zircon ε_Hf(t) values of −17.5 ∼ −7.1, consistent with derivation from the hydrous-melting of orthogneiss. The lower Zhibai formation experienced higher-pressure melting during the Late Oligocene-Early Miocene, while the upper Pai formation experienced moderate-pressures melting. Early Miocene anatexis and exhumation in the Zhibai formation correlate with Himalayan crustal uplift. Late Miocene exhumation and decompression-driven hydrous-melting across all formations reflect rapid crustal uplift linked to local crustal-scale mechanical-thermal coupling. The study highlights how pressure regimes, source heterogeneity, and melt mechanisms govern multi-stage anatexis at varying depths, tightly linked to the Himalayan orogen's evolution.</div></div>","PeriodicalId":18070,"journal":{"name":"Lithos","volume":"506 ","pages":"Article 108026"},"PeriodicalIF":2.9,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738306","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":"Hygrothermobarometry for granites using melt inclusions in zircon","authors":"Yuka Taniwaki ,&nbsp;Toko Fukui ,&nbsp;Satoshi Saito ,&nbsp;Mayuko Fukuyama","doi":"10.1016/j.lithos.2025.108029","DOIUrl":"10.1016/j.lithos.2025.108029","url":null,"abstract":"<div><div>Granites (<em>sensu lato</em>) represent unerupted products of felsic magmas in the crust. In this study, we estimate water contents of melts and pressure–temperature conditions of zircon crystallization in granitic magma using melt inclusions in zircon, a ubiquitous accessory mineral in granites. Homogenization experiments of polymineralic inclusions hosted in zircon have been conducted for granitoid samples from the Miocene Kaikomagatake and Miuchi plutons in Japan, which were emplaced at different crustal levels. The homogenized melt inclusions have high SiO₂ contents (77–79 wt% anhydrous basis), implying that they represent fractionated interstitial melts trapped in growing zircon crystals. The absence of older inherited U<img>Pb ages precludes the possibility that the zircon and its melt inclusions were derived from the surrounding metasedimentary rocks. Higher water contents for the Kaikomagatake pluton (4.8–9.0 wt% H₂O) than the Miuchi pluton (2.4–6.0 wt% H₂O) are revealed, which can be attributed to the difference in emplacement depths between the plutons. We examine the results of five melt geobarometers and find that a recently proposed machine learning-based melt–phase assemblage geobarometer (MagMaTaB) yields reasonable pressures for both the Kaikomagatake and Miuchi plutons of 303–185 MPa and 235–92 MPa, respectively, interpreted as zircon crystallization pressures. The melt inclusion data plot along the H₂O solubility curve in the pressure–H₂O diagram, suggesting the high water activity of the fractionated interstitial melts within the magmas during zircon crystallization. The new thermobarometric estimates suggest that temperature increased with decreasing pressure for both plutons, which probably reflects the reheating of reservoirs during magma ascent.</div></div>","PeriodicalId":18070,"journal":{"name":"Lithos","volume":"504 ","pages":"Article 108029"},"PeriodicalIF":2.9,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143561852","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":"Metamorphic magnesite deposits of Brumado (Bahia, Brazil): Evidence from highly saline H2O-CO2 fluid inclusions","authors":"Ronald J. Bakker ,&nbsp;Johann G. Raith ,&nbsp;Elisabeth Hauzinger ,&nbsp;Walter Prochaska ,&nbsp;Christoph Stranzl","doi":"10.1016/j.lithos.2025.108035","DOIUrl":"10.1016/j.lithos.2025.108035","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Magnesite deposits in Brumado, Bahia, Brazil, occur in the Serra das Éguas, a mountain range, where an Archean greenstone belt is exposed within the Gaviao block in the Sao Francisco Craton in Eastern Brazil. A genetic model is designed using the properties and distribution of fluid and solid inclusions in magnesite. These inclusions are analysed with careful petrography, and several technical methods, such as microthermometry, Raman spectroscopy, cryo-Raman spectroscopy, and ion chromatography. Equations of state of complex water-gas-salt mixtures are used to establish pressure and temperature conditions of ore formation. Two different mineralization types of coarse-grained sparry magnesite are distinguished. Type 1 consists of a coarse-grained reddish coloured magnesite exposed at the Pedra Preta mine and at the Pedra de Ferro prospect, whereas type 2 is composed of more fine-grained, purely white magnesite currently produced at the Pomba mine and explored at the Pirajá prospect. Abundant finely dispersed hematite is found in the reddish coloured magnesite of the type 1 mineralization, and is nearly absent in white magnesite of the type 2 mineralization. Fluid inclusions are exceptionally large (up to 50 μm) and provide excellent objects for the estimation of properties with all analytical techniques. The fluid inclusion assemblages are homogeneous. A sequence of three types of fluid inclusions is observed in both magnesite deposits, that illustrates various gradual modifications of pore fluids properties during formation of the ore: 1. a decreasing content of CO&lt;sub&gt;2&lt;/sub&gt;, from about 21 mol% to trace amounts; 2. a decrease in volume fraction of the CO&lt;sub&gt;2&lt;/sub&gt;-rich phases; 3. a decrease in density of the CO&lt;sub&gt;2&lt;/sub&gt; phases; 4. nearly constant salinity of the aqueous phase (approximately 14 eq. mole% NaCl). Cryo-Raman spectroscopy reveals that CaCl&lt;sub&gt;2&lt;/sub&gt; is the major salt component within fluid inclusions, and the salinity can be expressed in terms of about 7 eq. mole% CaCl&lt;sub&gt;2&lt;/sub&gt;, which correspond to similar chlorinity values. The ionic ratio of Na/K and Na/Li is sensitive to metamorphic conditions, and can be used as paleo-geothermometer yielding about 320 °C for the white magnesite and 250 °C for the reddish coloured magnesite. However, these values are obtained from bulk analyses and must be regarded as mechanical mixed values of all types of inclusions within a sample. The triple halogen ion content (Cl-Br-I) is not affected by metamorphic processes and reveals the origin of salinity: an Archean bittern, which is the major source of magnesium. This highly saline H&lt;sub&gt;2&lt;/sub&gt;O-CO&lt;sub&gt;2&lt;/sub&gt; fluids with a high density were trapped under various metamorphic conditions in both types of magnesite of the Brumado deposits. Minimum trapping conditions of the fluid, and therefore of magnesite formation is about 670 °C and 371 MPa. The source of CO&lt;sub&gt;2&lt;/sub&gt; is of metamorphic origin. The consumption of both CO&lt;sub&gt;2&lt;","PeriodicalId":18070,"journal":{"name":"Lithos","volume":"504 ","pages":"Article 108035"},"PeriodicalIF":2.9,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143592837","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":"Nature and evolution of the Cenozoic lithospheric mantle beneath the northeastern Yangtze Craton, China: Insights from Sr-Nd-Pb-Os isotopes of peridotite xenoliths","authors":"Danyang Liu ,&nbsp;Jun Yan ,&nbsp;Jianxin Zhao ,&nbsp;Yuexing Feng ,&nbsp;Sinuo Wang","doi":"10.1016/j.lithos.2025.108025","DOIUrl":"10.1016/j.lithos.2025.108025","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The eastern North China Craton has undergone significant modification and destruction, with over 100 km of ancient lithospheric mantle lost from the Paleozoic to the Cenozoic. However, it remains unclear if the neighboring eastern Yangtze Craton, which is part of eastern China, underwent similar deep geological processes within the same geodynamic setting. This study examines peridotite xenoliths hosted by the Cenozoic basalts from the Subei Basin, located in the northeastern Yangtze Craton, using integrated analyses of petrology, major-trace elements, and Sr-Nd-Pb-Os isotopic compositions. The spinel lherzolite xenoliths exhibit porphyroclastic and granular textures, reflecting fertile and juvenile mantle compositions (whole-rock Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; = 2.09–3.73 wt%, Fo = 89.1–90.2). The Os isotopic ratios (&lt;sup&gt;187&lt;/sup&gt;Os/&lt;sup&gt;188&lt;/sup&gt;Os = 0.1208–0.1256) are consistent with those of the asthenosphere, as observed in abyssal peridotites. Two distinct trace element patterns are identified in the clinopyroxenes. Type-1 clinopyroxenes are slightly enriched in LREE and exhibit depleted Sr-Nd-Pb isotopic compositions (&lt;sup&gt;87&lt;/sup&gt;Sr/&lt;sup&gt;86&lt;/sup&gt;Sr = 0.7026–0.7031, ɛ&lt;sub&gt;Nd&lt;/sub&gt; = 8.9–12.3, (&lt;sup&gt;206&lt;/sup&gt;Pb/&lt;sup&gt;204&lt;/sup&gt;Pb)&lt;sub&gt;&lt;em&gt;i&lt;/em&gt;&lt;/sub&gt; = 17.840–18.135, (&lt;sup&gt;207&lt;/sup&gt;Pb/&lt;sup&gt;204&lt;/sup&gt;Pb)&lt;sub&gt;&lt;em&gt;i&lt;/em&gt;&lt;/sub&gt; = 15.419–15.474, (&lt;sup&gt;208&lt;/sup&gt;Pb/&lt;sup&gt;204&lt;/sup&gt;Pb)&lt;sub&gt;&lt;em&gt;i&lt;/em&gt;&lt;/sub&gt; = 37.732–38.115). In contrast, Type-2 clinopyroxenes are slightly depleted in LREE and exhibit more depleted Sr-Nd-Pb isotopic ratios (&lt;sup&gt;87&lt;/sup&gt;Sr/&lt;sup&gt;86&lt;/sup&gt;Sr = 0.7022–0.7027, ɛ&lt;sub&gt;Nd&lt;/sub&gt; = 10.5–23.0, (&lt;sup&gt;206&lt;/sup&gt;Pb/&lt;sup&gt;204&lt;/sup&gt;Pb)&lt;sub&gt;&lt;em&gt;i&lt;/em&gt;&lt;/sub&gt; = 17.114–17.856, (&lt;sup&gt;207&lt;/sup&gt;Pb/&lt;sup&gt;204&lt;/sup&gt;Pb)&lt;sub&gt;&lt;em&gt;i&lt;/em&gt;&lt;/sub&gt; = 15.365–15.461, (&lt;sup&gt;208&lt;/sup&gt;Pb/&lt;sup&gt;204&lt;/sup&gt;Pb)&lt;sub&gt;&lt;em&gt;i&lt;/em&gt;&lt;/sub&gt; = 37.011–37.728), resembling the depleted MORB mantle (DMM). These signatures and variations in trace elements and isotopes suggest that the peridotite xenoliths from the Subei Basin represent a newly accreted lithospheric mantle formed through the upwelling and cooling of the asthenosphere. Both peridotite types show low degrees of partial melting (&lt;10 %), with Type-1 likely experiencing slight metasomatism from silicate melt derived from subducting sediments. Despite distinct characteristics, both types indicate similar equilibrium temperatures, suggesting a common depth of origin. The integrated petrological and geochemical characteristics of the peridotite xenoliths indicate that the Cenozoic subcontinental lithospheric mantle beneath the northeastern Yangtze Craton was newly accreted through rapid upwelling and cooling of the asthenosphere following delamination of the low part of lithosphere. This study investigates the transformation of the lithospheric mantle beneath the northeastern Yangtze Craton in response to the extensional setting induced by the subduction and rollback of the paleo-Pacific Plate, including the comple","PeriodicalId":18070,"journal":{"name":"Lithos","volume":"502 ","pages":"Article 108025"},"PeriodicalIF":2.9,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553028","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":"The role of mafic input in highly evolved volcanism within the Altiplano-Puna Volcanic complex: A geochemical study of Cerro Chao","authors":"Loreto Hernández Prat ,&nbsp;Benigno Godoy ,&nbsp;Claudia Cannatelli ,&nbsp;Daniel Astudillo Manosalva ,&nbsp;Angelo Castruccio ,&nbsp;Stephen M. Elardo ,&nbsp;Brian Monteleone","doi":"10.1016/j.lithos.2025.108024","DOIUrl":"10.1016/j.lithos.2025.108024","url":null,"abstract":"<div><div>Cerro Chao is a crystal-rich dacitic coulée-type lava flow located within the Altiplano-Puna Magmatic Complex (APVC) in Northern Chile, being the largest lava body in the area (14 km long) and one of the largest silicic lava flows in the world. Together with a group of dacitic to rhyolitic lava domes &lt;1 Ma in age (i.e., Cerro La Torta, Chillahuita, Chanka and Chac-Inca), Cerro Chao represents the last steady-state stage of the APVC eruptive cycle. Through a petrological and geochemical study of melt inclusions hosted in plagioclase, amphibole, biotite, and quartz, we aim to present novel data on the composition of Cerro Chao's parental magma and highlight the role that the input of deeper, mafic magma had in the evolution and generation of shallow (∼ 4–8.5 km) parental magma bodies feeding the silica-rich domes. Chao's parental magma (68.8–80.1 wt% SiO₂) originated from a dacitic mush intruded by an andesitic to basaltic andesitic magma(s) (53–59 wt% SiO₂) from the Altiplano-Puna Magma Body (APMB) ascending between ∼20 to 8 km depth. This intrusion(s) caused mixing and later evolution of the magma through assimilation and fractional crystallization (AFC). As a result, the magma consisting of newly formed crystals, older mush crystal aggregates, and melt ascend diapirically through the heating mush. Additionally, unmixed mafic intrusion(s) contributed to the presence of these different xenocrystic glomerophyres. An injection of magma first triggered an explosive eruption, forming Phase 1 of Chao Dacite (<span><span>de Silva et al., 1994</span></span>). Then, during its ascent, degassing occurred, allowing the crystal-rich magma to rise through the upper crust via processes of stopping and dyking, eventually erupting effusively.</div></div>","PeriodicalId":18070,"journal":{"name":"Lithos","volume":"504 ","pages":"Article 108024"},"PeriodicalIF":2.9,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552546","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":"Genetic links of crustal radiogenic heating to peraluminous granites","authors":"Xiang-Chong Liu ,&nbsp;Guo-Hui Hu ,&nbsp;Fan-fen Hu ,&nbsp;Hui Wang ,&nbsp;Yong Wang","doi":"10.1016/j.lithos.2025.108028","DOIUrl":"10.1016/j.lithos.2025.108028","url":null,"abstract":"<div><div>Peraluminous granites are commonly considered to be the product of crustal reworking in continental interiors and have a genetic relationship to Sn-W-rare metals deposits (e.g., Li, Be, Nb, Ta, Cs, Rb), but the heat transfer mechanisms responsible for the formation of peraluminous magmas and the mantle roles in these physical processes remains controversial. To answer these questions, the origin of the Xingluokeng granite in the Wuyi terrain of South China, peraluminous granite hosting large-scale tungsten mineralization, was investigated using zircon U<img>Pb and Hf isotopic compositions and numerical modeling of heat transfer with geologically relevant ranges of the ancient crustal thickness and heat production. The strongly negative <span><math><msub><mi>ε</mi><mrow><mi>Hf</mi><mfenced><mrow><mn>150</mn><mspace></mspace><mi>Ma</mi></mrow></mfenced></mrow></msub></math></span> values (−25.72 – –7.01) of autocrysic zircons (ca. 150 Ma), varying within those of inherited zircons (600–1000 Ma), suggest no signature of mantle mass input. The Mesozoic upper crust heat production in the Wuyi terrain estimated from fine-grained clastic sediments has an average of 2.9 μW m⁻³, and amphibolite facies to granulite facies rocks, representing the middle-lower crust, have averages of 0.6–4 μ W m⁻³. These values are greater than the global present-day averages for continental crust (upper crust: 1.68 μW m⁻³; middle-lower crust: 0.19–1 μW m⁻³). The high heat production and moderate crustal thickening (∼50 km), together with a normal mantle heat flux, can cause partial melting of metasedimentary rocks in the middle–lower crust within a thermal relaxation period of ∼30–50 Ma. Crustal radiogenic heating also warms the lower crust and the upper mantle and facilitates partial melting of mafic rocks, leaving volumetrically minor mafic dykes coeval with peralumnious granites in the same regions. Therefore, minor mafic dykes are not convincing evidence for the mantle supplying heat or mass for the coeval peraluminous granites. High crustal heat production and crustal thickening is also shared by other regions in the Cathaysia Block, so the above implications may also be applicable to other Mesozoic peraluminous granites in South China.</div></div>","PeriodicalId":18070,"journal":{"name":"Lithos","volume":"504 ","pages":"Article 108028"},"PeriodicalIF":2.9,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552545","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}