Contributions to Mineralogy and Petrology最新文献

{"title":"Komatiitic parental magmas of the Archean Ujaragssuit Nunât ultramafic body, SW Greenland, identified from spinel chemistry","authors":"I. Nishio,&nbsp;T. Morishita,&nbsp;P. Waterton,&nbsp;A. Tamura,&nbsp;K. Itano,&nbsp;S. H. Serre,&nbsp;J. L. Plesner,&nbsp;K. Takahashi,&nbsp;K. Tani,&nbsp;Y. Harigane,&nbsp;H. Sawada,&nbsp;K. Szilas","doi":"10.1007/s00410-025-02208-6","DOIUrl":"10.1007/s00410-025-02208-6","url":null,"abstract":"<div><p>Archean and Proterozoic layered intrusions represent an important portion of the igneous rock archive and their parental magma composition may provide crucial insights into the Earth’s magmatic and geodynamic evolution. Both komatiitic and boninitic parental magmas have been suggested for several major Archean layered intrusions, which could imply different tectonic settings for their formation. We studied the ~ 3.2 Ga Ujaragssuit Nunât layered ultramafic body from southern West Greenland (Ujaragssuit ultramafic body), which contains some of Earth’s oldest chromitites. Spinel major and trace elements, and whole-rock platinum group element compositions in massive chromitites from the Ujaragssuit ultramafic body, largely preserve primary igneous compositions. In contrast, spinels from most silicate-dominated ultramafic rocks were altered by metamorphic and metasomatic events. We collated a large spinel dataset to investigate variations in their parental magma compositions and tectonic settings using multivariate statistical analysis. Both the massive chromitites from the Ujaragssuit ultramafic body and chromitites from other Archean and Proterozoic ultramafic layered intrusion show high Cr/(Cr + Al) and Ti/V ratios in spinel, and high whole-rock Ir and Ru contents, which are consistent with those of komatiitic spinel. The compositions of chromitites suggest that the parental magmas of the Ujaragssuit ultramafic body are komatiitic, implying that the formation of these layered intrusions was related to mantle plumes. Our recognition of a komatiitic ultramafic body in North Atlantic Craton, where no komatiite has previously been reported, suggests that komatiitic magmas were a common feature among cratons.</p></div>","PeriodicalId":526,"journal":{"name":"Contributions to Mineralogy and Petrology","volume":"180 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00410-025-02208-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465850","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 effect of high-pressure metasomatism on the boron isotope signature of subducted oceanic crust in the Raspas Complex (Ecuador)","authors":"Jie Dodo Xu,&nbsp;Horst R. Marschall,&nbsp;Axel Gerdes,&nbsp;Alexander Schmidt,&nbsp;Timm John","doi":"10.1007/s00410-025-02202-y","DOIUrl":"10.1007/s00410-025-02202-y","url":null,"abstract":"<div><p>Boron abundances and B isotopic compositions of well-characterized blueschists and eclogites from the Raspas Complex (Ecuador) were analyzed to improve the use of boron as a tracer for recycling at convergent margins. The MORB-type eclogite interacted with internally-derived fluids released from metabasalt during the transition from blueschist to eclogite, with input from sediments. During metasomatism, B was gradually leached from the MORB-type eclogites (decrease from 6<span>(upmu )</span>g/g to 1.5<span>(upmu )</span>g/g), and their B isotopic composition was driven to isotopically heavier values in the range of <span>(-)</span>7.4<span>(permille )</span> to <span>(-)</span>3.4<span>(permille )</span>. The B isotopic composition of the metasomatic fluid is estimated between <span>(-3)</span> and +1<span>(permille )</span>. The isotopic composition of the least metasomatized MORB-type eclogite samples (<span>({-7.4pm 0.7}{permille })</span>) is considered close to the B isotopic composition of the dehydrated AOC in the case of Raspas at the stage of deepest subduction and most extensive dehydration. This constitutes a decrease in <span>(delta ^{11}text {B})</span> of approximately 10<span>(permille )</span> from its likely pre-subduction AOC protolith. The blueschist experienced a type of high-pressure metasomatism that is distinct from the one that affected the MORB-type eclogites. The metasomatic fluids were internally-derived and released by metabasalt as well, but with more input from sediments. The metasomatic fluid had a B isotope signature of approximately <span>(-)</span>5.2<span>(permille )</span>. The zoisite eclogite samples show a very distinct mineralogical and geochemical composition that records the highest degree of high-pressure metasomatic overprint. Their elemental and isotopic composition was thereby set to <span>(text {[B]}={2.1pm 0.3}upmu hbox {g/g})</span> and <span>(delta ^{11}text {B}={-5.8pm 1.8}{permille })</span>. As demonstrated in previous studies, the high-pressure metasomatic fluid that caused the metasomatic overprint was mainly derived from– or interacted with– serpentinite, but had admixed components from metabasalts and metasediments. The B isotopic composition of the respective fluid is estimated at <span>({-2.6} {permille })</span>, which overlaps with the composition of most volcanic arc basalts. This study, therefore shows, that metasomatic fluids that migrated through the Raspas slab at a depth of 50–70km had a B isotopic composition between <span>(-5.2)</span> to +1<span>(permille )</span> and were, thus, significantly heavier than that of the mantle.</p></div>","PeriodicalId":526,"journal":{"name":"Contributions to Mineralogy and Petrology","volume":"180 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00410-025-02202-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446487","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":"Geochemistry and Sr–Nd–Pb isotope geology of intraplate cenozoic basaltic volcanism of NE Brazil: remnant of an aborted mid-ocean ridge?","authors":"Zorano Sérgio de Souza,&nbsp;Frederico Castro Jobim Vilalva,&nbsp;Jean-Michel Lafon,&nbsp;Chao Wang,&nbsp;Xiao-Dong Deng,&nbsp;Jian-Wei Li,&nbsp;Elton Luiz Dantas,&nbsp;Rafael Gonçalves da Motta,&nbsp;Joyce Lorena Oliveira","doi":"10.1007/s00410-025-02207-7","DOIUrl":"10.1007/s00410-025-02207-7","url":null,"abstract":"<div><p>Upper Cretaceous to Miocene continental volcanism in NE Brazil spans 350 km in a N–S direction and 60 km in width, forming the Macau-Queimadas alignment (MQA). This study combines fieldwork, petrography, geochemistry, and Sr–Nd–Pb isotopes to explore its origin and evolution. The MQA consists of volcanic and hypabyssal mafic rocks intruding Cretaceous and Precambrian basement rocks, divided into two groups: (i) alkaline (foidite to trachy-basalt); and (ii) subalkaline (basalt and basaltic andesite). Both are sodic and LREE-enriched, with distinct La/Yb ratios. The alkaline group reflects an asthenospheric source (Nd model age of 1.1–0.4 Ga), while the subalkaline group incorporates an older lithospheric component (Nd model age of 2.1–1.2 Ga). These magmas originated from picritic parental melts, with &lt; 15% melting for the alkaline group and ~ 25–30% melting for the subalkaline group, derived from spinel- to garnet-bearing peridotite. Differentiated series formed by successive small melt volumes, with some samples undergoing crustal fractional crystallization of clinopyroxene + olivine + plagioclase (alkaline group), and clinopyroxene + orthopyroxene + Ca-plagioclase (subalkaline group). The persistence of basaltic magmatism over ~ 90 Myr indicates sustained upper mantle melting. The alignment of volcanics, its association with a positive geoid anomaly, and its parallelism with the Mid-Atlantic Ridge suggest the MQA may represent an aborted ridge that never progressed to an oceanic stage.</p></div>","PeriodicalId":526,"journal":{"name":"Contributions to Mineralogy and Petrology","volume":"180 2","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361859","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":"Recycling of subduction-modified refractory mantle beneath the Marion Rise, Southwest Indian Ridge","authors":"Yin-Zheng Lin,&nbsp;Chuan-Zhou Liu,&nbsp;Wei-Qi Zhang,&nbsp;Zhen-Yu Zhang,&nbsp;Chang Zhang,&nbsp;Tong Liu","doi":"10.1007/s00410-025-02205-9","DOIUrl":"10.1007/s00410-025-02205-9","url":null,"abstract":"<div><p>The Marion Rise, located in the central portion of the Southwest Indian Ridge (SWIR), marks a relief high but is overall covered with a thin crust, and thus is inferred to be supported by depleted buoyant mantle. However, direct evidence of the regional mantle compositions from abyssal peridotites are still rare for such a hypothesis. This study presents whole rock and mineral compositions of 34 abyssal peridotites dredged from 7 sites between the Discovery and Indomed fracture zones on the Marion Rise. The samples are divided into low-Cr# (Cr# = 0.23–0.33) and high-Cr# (Cr# = 0.40–0.57) groups. The high-Cr# group samples display highly refractory characteristics (whole rock Al₂O₃ contents down to 0.52 wt%), which are reinforced by the depleted pyroxene compositions that indicate partial melting of up to &gt; 18%. Nonetheless, the overall high extents of melting indicated by the peridotites are inconsistent with the regional thin crust, hence require an inherited origin of the melting signatures. Moreover, the Ti and Yb (Y) concentrations of clinopyroxenes (orthopyroxenes) in the high-Cr# group are too depleted to be residues of anhydrous melting at mid-ocean ridges, but instead suggest for a hydrous melting history near subduction zones. Collectively, we fill in a piece of the puzzle of mantle heterogeneity beneath the SWIR, by providing solid evidence for the existence of a highly refractory mantle beneath the Marion Rise. These mantle components carry subduction-modified characteristics, and very likely have a recycled mantle wedge origin.</p></div>","PeriodicalId":526,"journal":{"name":"Contributions to Mineralogy and Petrology","volume":"180 2","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108226","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":"Correction to: Buoyancy-driven propagation of an isolated fluid-filled crack in rock: implication for fluid transport in metamorphism","authors":"Kui Han,&nbsp;Xinzhuan Guo,&nbsp;Hanyong Liu,&nbsp;Fengbao Ji","doi":"10.1007/s00410-025-02199-4","DOIUrl":"10.1007/s00410-025-02199-4","url":null,"abstract":"","PeriodicalId":526,"journal":{"name":"Contributions to Mineralogy and Petrology","volume":"180 2","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143107950","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":"Remobilization of century-old magmas during the 2018 basaltic caldera-forming eruption at Kīlauea Volcano (Hawai‘i)","authors":"Adrien J. Mourey,&nbsp;Euan J. F. Mutch,&nbsp;Thomas Shea","doi":"10.1007/s00410-025-02204-w","DOIUrl":"10.1007/s00410-025-02204-w","url":null,"abstract":"<div><p>The recent eruptions at Kīlauea Volcano (Hawai‘i) raised some fundamental questions on the longevity and the preservation of eruptible magma batches left over from previous eruptions. Fingerprinting magma batches at Kīlauea through time with bulk and glass compositions is challenging. Narrow compositional changes (e.g., Nb/Y ratio) in matrix glasses occur over time because of repeated magma mixing, and residence timescales of stored evolved magmas in the lower East Rift Zone are underconstrained. To evaluate the diversity in composition and the minimum residence timescales in Rift Zone magmas, we analyzed major and trace elements in plagioclase and matrix glasses from selected samples that erupted in the first weeks of the 2018 Kīlauea eruption. Plagioclase crystals in these samples represent mixed populations with a range in composition spanning An_30-80, corresponding to rhyodacitic to basaltic compositions and temperatures from 950 to 1200 °C. Diffusion modeling of Mg in these plagioclase crystals indicate minimum crystal residence timescales that range from &lt; 1 to ~ 480 years. The complex zoning patterns in plagioclase (and resorptions) together with the protracted storage timescales from diffusion modeling imply that magmas from the East Rift Zone accumulated various plagioclase populations recording magma mixing events that occurred a few years to a few centuries before the 2018 eruption. The diversity of the magma batches (observed with An-Mg compositions in plagioclase) erupted in a single eruption offers research pathways to potentially estimate the frequency, volume and eruptibility of these evolved magmas, thereby refining the risk in the region.</p></div>","PeriodicalId":526,"journal":{"name":"Contributions to Mineralogy and Petrology","volume":"180 2","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109871","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 spinel to garnet phase transition in the systems MgO-Al2O3-SiO2 and CaO-MgO-Al2O3-SiO2: new experiments to resolve long-standing discrepancies","authors":"Nicholas Farmer,&nbsp;Hugh St. C. O’Neill,&nbsp;Eleanor C. R. Green","doi":"10.1007/s00410-025-02203-x","DOIUrl":"10.1007/s00410-025-02203-x","url":null,"abstract":"<div><p>The pressure and temperature conditions of the transition from spinel to garnet as the stable aluminous phase in peridotite lithologies of the upper mantle is integral to elucidating the tectonic significance of the ‘garnet signature’ in basalts. It provides an essential constraint on models of mantle partial melting and oceanic crust formation. Existing experimental results on the univariant phase transition in the simple systems MgO-Al₂O₃-SiO₂ (MAS) and CaO-MgO-Al₂O₃-SiO₂ (CMAS) are mutually inconsistent. To resolve this, we have re-determined the <i>P-T</i> coordinates of the univariant transition in both synthetic systems by running experiments containing both systems simultaneously in the piston-cylinder apparatus, along with the MgO-ZnO pressure sensor. These experiments show a ~ 0.4 GPa difference in the pressure of the spinel/garnet phase transition between the two chemical systems at 1400 ºC, double that inferred from a compilation of existing experimental data. Absolute pressure in these experiments can be verified using the MgO-ZnO sensor. The results imply that the thermodynamic data used in recent mineral equations of state based on the Holland-Powell thermodynamic dataset are substantially correct.</p></div>","PeriodicalId":526,"journal":{"name":"Contributions to Mineralogy and Petrology","volume":"180 2","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00410-025-02203-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143110177","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":"A grain boundary model of garnet growth","authors":"Frank S. Spear","doi":"10.1007/s00410-025-02201-z","DOIUrl":"10.1007/s00410-025-02201-z","url":null,"abstract":"<div><p>Numerical models for the growth of garnet are presented to evaluate the relative significance of reaction-limited growth and diffusion-limited growth following garnet nucleation after significant overstepping of the equilibrium garnet-in reaction. Reactions are only permitted among phases that are adjacent across grain boundaries and the extent of reaction at a given reaction site is scaled to the local amount of chemical affinity available to the two or three reactant phases relative to the grain boundary composition. This local affinity is dissipated as the local reaction proceeds, which changes the composition of the adjacent grain boundary “phase” and sets up chemical gradients that drive diffusion along the grain boundaries. Reactions proceed until all affinity is exhausted at which point the rock is essentially at equilibrium. Two extremes are modeled. Reaction-limited growth is modeled as infinitely rapid grain boundary diffusion whereas diffusion-limited growth is modeled by assuming that reactions proceed infinitely fast such that the supply of nutrients and removal of waste products from a reaction site is restricted by the rate of diffusion. Models are presented with model assemblages chlorite + quartz + garnet and chlorite + quartz + muscovite + biotite + plagioclase + garnet. Reaction-limited models result in garnets displaying well-formed “bell-shaped” Mn zoning profiles with all garnet crystals showing similar amounts of growth and zoning profiles. Diffusion-limited models result in mineral growth or consumption that is texture-sensitive such that the amount of consumption or production of a phase depends on the location of the crystal in the sample and the proximity of other phases. For example, the total amount of garnet continues to increase for the duration of diffusion-limited models although locally an individual garnet crystal may first grow and then be consumed. Mn zoning in models with short diffusion times display distinct “peaks” in the central garnet cores, in contrast to the bell-shaped profiles in reaction-limited models. With increasing diffusion times, these Mn zoning profiles evolve towards bell-shapes. These models demonstrate that diffusion-limited growth of garnet porphyroblasts may result in textural and compositional complexities that are not encapsulated by bulk-rock thermodynamic modeling.</p></div>","PeriodicalId":526,"journal":{"name":"Contributions to Mineralogy and Petrology","volume":"180 2","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00410-025-02201-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995641","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":"Crust‐mantle decoupling in the Gakkel Ridge induced by strong heterogeneity of the asthenosphere","authors":"Yang Xu,&nbsp;Chuan-Zhou Liu,&nbsp;Yin-Zheng Lin,&nbsp;Bo-Da Liu","doi":"10.1007/s00410-025-02198-5","DOIUrl":"10.1007/s00410-025-02198-5","url":null,"abstract":"<div><p>Abyssal peridotites can provide complementary information on the compositional features of the asthenosphere, as the refractory mantle within the asthenosphere contributes little to the genesis of mid-ocean ridge basalts (MORB). Here we present major and trace elements of ~ 70 abyssal peridotites from the Sparsely Magmatic Zone (SMZ) and Eastern Volcanic Zone (EVZ) of the Gakkel Ridge, which are residues of the asthenosphere that have undergone &lt; 15% partial melting. Their clinopyroxenes display LREE-depleted and LREE-flat patterns, the latter of which resulted from refertilization by quasi-instantaneous melts in the melting zone beneath the mid-ocean ridge. Compositions of the Gakkel peridotites are highly variable along the ridge axis, which cannot be attributed to the spatial variation of temperature of the asthenosphere. The estimated degrees of melting of the Gakkel abyssal peridotites are higher than the values inferred by seismic thickness of ocean crust along the SMZ and EVZ. This implies the Gakkel abyssal peridotites inherit ancient melting prior to their entering the Gakkel Ridge, which also causes the crust-mantle decoupling in compositions. Moreover, compositions of the Gakkel peridotites differs significantly from subduction-related peridotites. We suggest the asthenosphere beneath the Gakkel Ridge is highly heterogeneous in compositions, which is the culprit of crust-mantle geochemical decoupling. Enriched MORB erupted in the SMZ region were derived from small amounts of enriched components within the asthenosphere, which cannot be represented by the abyssal peridotites exposed in this region.</p></div>","PeriodicalId":526,"journal":{"name":"Contributions to Mineralogy and Petrology","volume":"180 2","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995582","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":"Quantifying the partial melting of Himalayan Metamorphic core in Eastern Himalaya: implications for crustal rheology","authors":"Purbajyoti Phukon,&nbsp;Md. Sunny Hussain,&nbsp;Takeshi Imayama,&nbsp;Jia-Min Wang,&nbsp;Kazumasa Aoki,&nbsp;Sanjeeb Behera","doi":"10.1007/s00410-025-02200-0","DOIUrl":"10.1007/s00410-025-02200-0","url":null,"abstract":"<div><p>The Himalayan orogeny caused partial melting of rocks within the Greater Himalayan Sequence (GHS), forming migmatites. The extensive occurrence of such migmatites in the lower structural level of the GHS (GHS_L) is a distinctive feature of the Western Arunachal Himalaya (WAH), situated in eastern part of the orogen; meanwhile leucogranite is predominantly found in the highest reaches of the GHS_L. A comprehensive multi-method study incorporating field observations, petrography, phase equilibrium modelling, geochemical analysis, and zircon U–Pb and monazite U–Th–Pb geochronology was conducted on migmatitic paragneiss and leucogranites from the GHS_L along the Bomdila-Tawang section of the WAH. P–T pseudosection modelling reveals a clockwise P–T path characterized by prograde burial and heating, significant melt production, and nearly isothermal decompression during melt solidification. Structural observations, including concordant and discordant relationships between leucosomes and gneissic bands, suggest that deformation established pathways for melt migration. Zircon U–Pb dates reveal bimodal protolith ages of ~ 1350 Ma (Ectasian) and ~ 900 Ma (Tonian). Insufficient zircon overgrowth (&lt; 20 μm), likely due to extensive melt extraction during suprasolidus metamorphism, precludes younger age determination. Monazite U-Th-Pb age indicates peak metamorphism of the GHS_L at ca. 25–26 Ma, synchronous with MCT initiation in the WAH. Melt generation at peak metamorphic conditions in the GHS_L reached ~ 16 vol% in stromatic metatexites and ~ 26 vol% in layered diatexites and of these generated melts, &gt; 50% escaped at depths of ~ 30–34 km. This extensive migration formed complex leucosome networks, contributing to regional leucogranite distribution and rheological weakening, enabling ductile flow within the GHS.</p></div>","PeriodicalId":526,"journal":{"name":"Contributions to Mineralogy and Petrology","volume":"180 2","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142976653","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}