The recycling of carbonates between the Earth's surface and its interior plays a critical role in global carbon cycling and atmospheric CO2 variations. This study investigates the fate of subducted carbonates from the NeoTethyan Ocean and their contribution to Cenozoic atmospheric CO2 through the analysis of Cenozoic alkaline basalts from the Tianshan basalt province in western China. Combining Mg-Ca-Sr-Nd-Pb isotopes, major and trace element geochemistry, numerical modeling, and through systematic evaluation of potential influences from both source lithology and magmatic processes, we demonstrate that the distinctive low delta 26Mg (-0.50 to -0.37 %o) and delta 44/40Ca (0.48 to 0.86 %o) values indicate a mantle source metasomatized by recycled marine carbonates, dominated by dolomite and magnesite. These carbonates were transported into the mantle transition zone (MTZ) via the subduction of the Neo-Tethyan oceanic slab, which stagnated and later contributed to mantle melting and magmatic CO2 degassing during the Eocene. Our calculations reveal high magmatic CO2 degassing fluxes (-0.3 - 0.5 Pg/a) from the Tianshan basalt province, comparable to those of the India-Asia collision-related magmatism. The temporal correlation between these fluxes and Cenozoic atmospheric CO2 variations suggests that the Tianshan basalt province and similar intraplate volcanic systems substantially contributed to Cenozoic atmospheric CO2 changes and paleoclimatic shifts. This study provides direct evidence for deep carbon recycling from subducted oceanic carbonates to mantle sources and highlights the importance of intraplate magmatism in regulating Earth's carbon cycle and climate.

Neoproterozoic continental arc magmatism in the western Yangtze Block (South China) provides critical insights into early crust-mantle evolution during circum-Rodinia subduction-accretionary orogenesis. However, the specific processes of Neoproterozoic continental crustal growth and stratification remain unclear. Herein, we present a comprehensive synthesis of mineral chemistry, zircon U-Pb-Hf isotopes, whole-rock major and trace elements as well as SrNd isotopes from representative Neoproterozoic Igneous Intrusive Complexes (NIICs) in the western Yangtze Block, including the Tianquan (TIC; ca. 833-825 Ma) and Shimian complexes (SIC; ca. 781-779 Ma) in this study, alongside the previously reported Nanba (NIC; ca. 796-790 Ma) and Luding complexes (LIC; ca. 783-779 Ma). The NIICs comprise mafic gabbros through intermediate diorites to highly fractionated silica-rich granitoids, suggesting a coherent calc-alkaline differentiation trend. They exhibit variable but predominantly depleted whole-rock SrNd (e.g., TIC: epsilon Nd(t) = -0.08 similar to +4.55; NIC: epsilon Nd(t) = -0.60 similar to +1.91; LIC: epsilon Nd(t) = +2.35 similar to +5.10; SIC: epsilon Nd(t) = +0.50 similar to +6.07) and zircon Hf isotopes (TIC: mean epsilon Hf(t) = +7.75 similar to +11.89; NIC: mean epsilon Hf(t) = +4.33 similar to +5.66; LIC: epsilon Hf(t) = +4.03 similar to +7.69; SIC: epsilon Hf(t) = +5.69 similar to +9.81), indicating a heterogeneous mantle source metasomatized by subducted components. Combined with "crust-like" trace element signatures, systematic whole-rock compositional variations, and hornblende P-T estimates, the NIICs represent middle-upper crustal sections, which underscore a three-stage evolution for Neoproterozoic continental arc crustal growth and fractionation: (1) the generation of primary basaltic melts from heterogeneous metasomatized mantle source infiltrated by subducted components; (2) the long-lived supply of metasomatized mantle-derived melts, magma mixing, and polybaric crystallization-driven differentiation within a trans-crustal magmatic system; and (3) extraction of high-silica melts in a shallow mush reservoir. Integrated with previous studies, our findings demonstrate that this complex array of petrogenetic processes-alongside the partial melting of diverse crustal sources-ultimately governed the maturation and vertical stratification of the Neoproterozoic continental arc crust in the western Yangtze Block.

Although the Youjiang basin in southwest China is the second-largest Carlin-type gold district worldwide, the sources of the gold in this district remain considerably debated. This study, using laser ablation-inductively coupled plasma-mass spectrometry and secondary ion mass spectrometry, investigated the trace element and sulfur isotope compositions of the pre-ore and ore pyrite in the Yata gold deposit. In this deposit, pre-ore pyrite occurs as nodules (Sed-Py0) in the carbonaceous sedimentary rocks, or as a core (Ore-Py1) characterized by irregularly shaped porous aggregates (locally as framboids) in ores, both of which are considered to be sedimentary and/or diagenetic in origin. Ore pyrite consists of an irregular As-rich mantle (Ore-Py2) and an As-poor rim (Ore-Py3) with subhedral crystals. Trace element analysis indicates that the above pyrite generations contain average concentrations of gold of 0.2 ppm for Sed-Py0, 8.9 ppm for Ore-Py1, 30.7 ppm for Ore-Py2, and 391.2 ppm for Ore-Py3. The latter three generations of ore pyrite yield delta 34S values ranging from +3.7 %o to +7.4 %o, +4.9 %o to +9.0 %o, and +6.1 %o to +9.2 %o, respectively. Pre-enrichment of Au, as well as As, and Sb in sedimentary/diagenetic pyrite, combined with the indistinguishable sulfur isotopes between pre-ore and ore pyrite, collectively supports a sedimentary rock origin of gold that accounts for the Yata Carlin-type gold deposit in the Youjiang basin.

Rapid uplift, denudation and recycling of continental arcs intimately link surface processes and deep crustal magmatism. However, direct petrological records of such rapid surface-crust recycling remain scarce. Here, we investigated Late Permian (256–250 Ma) granitic rocks from Hainan Island, South China, which formed within the eastern Paleo-Tethyan arc system. New elemental and isotopic data reveal a decoupling between whole-rock elemental geochemistry and oxygen isotopes in zircon. The studied rocks are metaluminous in composition (A/CNK < 1.1) and show an affinity with I-type granites. Moreover, their zircon Hf isotopic compositions overlap with those of ∼272–265 Ma mafic to intermediate arc rocks in the region, indicating their derivation from juvenile arc igneous protoliths. In contrast, their zircon δ18O values (7.83–16.06‰; mean 10.55‰ ± 0.32; 2SD) are higher than those of juvenile arc magmatic rocks (generally δ18O < 7‰) and are comparable to those of S-type granites (generally δ18O > 8‰). This implies that the protoliths of these Late Permian granitic rocks had experienced some degree of low-temperature water–rock interaction at Earth's surface. This elemental-isotopic decoupling is interpreted to reflect a rapid denudation and recycling loop within a Paleo-Tethyan continental arc. Tectonic uplift exposed juvenile igneous protoliths to surface conditions, where low-temperature water-rock interaction elevated their δ18O signatures. The weathered materials were then rapidly eroded, transported over short distances, and buried and remelted within a back-arc system. This scenario provides the most plausible explanation for the observed decoupling between whole-rock I-type mineralogical and elemental characteristics and zircon oxygen isotopic compositions in the Late Permian granitic rocks from Hainan Island, South China. Such decoupling may represent an important yet underrecognized aspect of continental arc evolution, reflecting efficient surface-deep coupling. Enhanced exposure and weathering of juvenile arc rocks likely promoted silicate weathering and potentially increased atmospheric CO₂ consumption during the Late Permian, with implications for contemporaneous climate evolution.

Carbon cycling into Earth's interior regulates long-term climate and habitability, yet the fate of subducted sedimentary carbon remains widely debated. Competing models predict either efficient carbon release from the subducting slab and surface return or massive deep sequestration into the mantle. Here, we present coupled Mg and Zn isotope systematics of Oligocene adakite-like granites derived from partially melted metasediments previously relaminated into the lower continental crust. The granites display variable delta 26Mg (-0.41%0 to +0.02%0) and delta 66Zn (0.27%0 to 0.46%0) values that define a negative correlation, trending from silicate sediment signatures toward isotopically lighter Mg and heavier Zn characteristic of carbonates. These signatures indicate recycled contribution from carbonate-bearing sediments to the magma source. We propose that diapiric relamination of carbonate-bearing sediments during subduction represents an efficient mechanism for storing carbon in the deep crust, thereby helping to resolve the imbalance between subducted and released carbon at convergent margins. Partial melting of such relaminated carbonate during the postcollision stage may subsequently act as a potential driver of atmospheric CO2.

The reconstruction of the lunar bombardment history is pivotal to understanding the evolution of Earth-Moon system. So far, it heavily depends on geochronological studies of lunar nearside samples but lacks direct sample constraints from the lunar farside. Here, we present 28 single-clast 40Ar/39Ar ages of impact melt rocks returned by the Chang'e-6 mission. They reveal impact events spanning from ∼4.33 to ∼1.13 billion years (Ga). In particular, three melt clasts date to ∼4.16 Ga, consistent with the recent dating of the Apollo basin, and only two ages fall at 4.0 to 3.7 Ga. The presence of older ages (>4.0 Ga) and lack of predominant age around ∼3.9 Ga suggest that the lunar farside bombardment was not dominated by a cataclysmic spike but by a smooth long-term decline punctuated by later impacts.

The reconstruction of the lunar bombardment history is pivotal to understanding the evolution of Earth-Moon system. So far, it heavily depends on geochronological studies of lunar nearside samples but lacks direct sample constraints from the lunar farside. Here, we present 28 single-clast 40 Ar/ 39 Ar ages of impact melt rocks returned by the Chang’e-6 mission. They reveal impact events spanning from ∼4.33 to ∼1.13 billion years (Ga). In particular, three melt clasts date to ∼4.16 Ga, consistent with the recent dating of the Apollo basin, and only two ages fall at 4.0 to 3.7 Ga. The presence of older ages (>4.0 Ga) and lack of predominant age around ∼3.9 Ga suggest that the lunar farside bombardment was not dominated by a cataclysmic spike but by a smooth long-term decline punctuated by later impacts.

Geological constraints and modelling results reveal major yet poorly understood changes in Earth's tectonic regimes during the late Archaean and Proterozoic. These changes are associated with supercontinent cycles, a primary archive of lithosphere and convecting mantle behaviour, and impact orogen duration and thermal state. However, the lack of precise data on orogen duration during Columbia assembly limits our understanding of the long-term tectonic evolution and comparison with younger orogens. Through in-situ garnet Lu-Hf and monazite microdomain U-Pb geochronology, here we constrain a 220 Myr hot collisional orogen during Columbia assembly, significantly longer than contemporary cold orogens (110-160 Myr). Secular changes in collisional orogen duration indicate a non-monotonic trend from Neoarchaean to Neoproterozoic. This trend implies enhanced plate rigidity and mobility during Columbia assembly, followed by a marked decline during Rodinia assembly, consistent with inferred plate velocity proxies. These findings support evolving tectonic regimes alternating between sluggish lid and more active plate tectonics during the Neoarchaean-Proterozoic.

The formation of giant porphyry deposits requires the accumulation of up to billions of tons of volatiles (H2O, Cl, and S) in an evolving trans-crustal magma system, followed by their focused release to the hydrothermal system via volatile exsolution in the upper crustal magma chamber. However, it remains unclear whether ore-forming and ore-barren magmatic pulses derived from the same parental magma system differ in initial volatile compositions or exsolution conditions. This uncertainty hinders our comprehension of how massive volatiles enrich and deliver the key drivers of porphyry mineralization. In this work, we investigate zircon water contents and zircon-hosted apatite volatile compositions of the pre-ore (109.7 +/- 0.8 Ma), syn-ore (103.1 +/- 1.1 Ma), and post-ore (98.1 +/- 1.1 Ma) intrusions of the Zijinshan ore field (ZOF). These data, along with numerical modelling, allow us to illustrate the volatile evolution of the magmatic system which sourced the largest Cretaceous porphyry Cu-Mo deposit in South China. Although geochemically similar, these co-sourced magmas exhibit distinct volatile compositions and evolution patterns. Zircon-hosted apatite inclusions from the syn-ore porphyry show highly variable Cl (0.14-2.94 wt%) and F (0.04-3.37 wt%) contents, whereas apatite from the pre-ore and post-ore intrusions displays more restricted halogen variation (0.62-2.70 wt% Cl, and 0.41-1.56 wt% F). Numerical modelling of apatite evolutionary trends suggests that the syn-ore magma had the highest initial melt H2O (similar to 5.0 wt%) and Cl (similar to 1300 ppm) contents, exsolving fluids with average aggregated salinity of 3.24 +/- 0.57 wt% NaCleq at the deepest level. These results align with the zircon OH- contents and biotite Al-thermobarometers, which indicate the highest saturation pressure (similar to 211 MPa) for the syn-ore porphyry. We suggest that fluid exsolution from magma with moderate Cl content at > 200 MPa optimises Cl-Cu extraction efficiency and promotes the formation of connected fluid networks throughout the magma chamber, facilitating upward fluid migration and subsequent mineralisation. In contrast, modelling indicates that the pre-ore magma had an intermediate initial melt H2O (similar to 4.0 wt%) but the lowest Cl (similar to 700 ppm) contents, generating less saline fluids (< 3.0 wt% NaCleq), which hampered metal extraction. The post-ore magma, despite relatively high initial Cl (similar to 1100 ppm) and comparable fluid salinity (3.36 +/- 1.40 wt% NaCleq), had the lowest H2O (3.72 +/- 0.70 wt%) and saturated at the lowest pressure (similar to 78 MPa), limiting Cu extraction, exsolved fluid amount, and focused fluid flux. Our findings indicate that the syn-ore volatile enrichment occurred primarily within the lower-crustal magma reservoir. In the absence of isotopic evidence for direct mafic recharge, we propose that fluids derived from underplating mafic magmas, rather than direct magma mixing, provided the critical volatile budget required for the ZOF porphyry mineralisation.

The deep water cycle represents a crucial link between Earth's surface and interior, profoundly influencing tectonic processes, magmatic activity, and crustal evolution. However, the pathways and mechanisms of water transport from the deep mantle to the continental crust remain poorly constrained. This study presents an integrated analysis of zircon water content, U-Pb-Hf-O isotopes, and whole-rock geochemistry from granulite xenoliths in the Tuoyun Basin, Western Tianshan. Three generations of zircons are identified: Neoproterozoic protolith zircons (similar to 800-600 Ma) with high water contents (median: similar to 404 ppm), Paleozoic-Mesozoic metamorphic zircons (similar to 600-100 Ma) displaying pronounced water depletion (median: similar to 55 ppm), and CretaceousPaleogene host-basalt zircons with intermediate water contents (median: not similar to 166 ppm). The elevated water contents coupled with low delta O-18 values in the protolith and host-basalt zircons point to magma water derived from a mantle-derived source rather than supracrustal contributions. The H2O-rich magma, positive Nb and Ta anomalies, and enriched Hf isotopes, further suggest that the parent magmas of granulite were likely derived from a hydrous mantle transition zone. The contrasting water contents of protolith and metamorphic zircons reveal a two-stage water transport process: hydrous mantle-derived magmas underplated the lower crust to form the protolith, and subsequent high-grade metamorphism dehydrated these rocks, releasing fluids that ascended to trigger mid-crustal water-fluxed melting. We propose that granulite dehydration in the lower crust represents a key mechanism for transporting mantle-derived water into the continental crust, linking deep-Earth water cycling with continental evolution.

The origin of lunar water-whether inherited during its formation (endogenous) or delivered later (exogenous)-remains a fundamental question in planetary science. Previous studies relying on hydrous minerals or melt inclusions are often compromised by post-magmatic processes. Zircon, with robust physico-chemical stability, serves as a superior archive for preserving primary magmatic composition. Here, we report the first SIMS measurements of water content and hydrogen isotopes in a ca.similar to 4.38 Ga zircon from lunar meteorite NWA 10049. The zircon exhibits a distinct core-rim structure with anomalous H2O-delta D compositions: while the core maintains relatively homogeneous water content (735 to 1164 mu g/g) with elevated delta D (+1320 to +1882 parts per thousand), the rim displays variable and inversely correlated water content (879 to 4268 mu g/g) and delta D (+1879 to +250 parts per thousand). Such H2O-delta D systematics-combined with geochemical and petrological signatures-precludes magmatic degassing or post-magmatic alteration. Instead, we attribute these variations to magma mixing and the subsequent assimilation of heterogeneous exogenous hydrous materials within a massive impact melt sheet. Our findings provide key evidence for the accretion of meteoritic material into the lunar interior before 4.38 Ga, which delivered substantial amounts of water and likely played a critical role in shaping the composition and spatial distribution of volatiles in the early Moon.

The anisotropy of magnetic susceptibility is widely applied to infer the magma flow direction in dikes and to assess broader geological implications. The “normal” magnetic fabric is characterized by a magnetic lineation parallel to the magma flow and a magnetic foliation that is subparallel to or imbricated against the dike walls. However, interpreting new results from the Gubaoquan doleritic dikes in NW China proves challenging. To elucidate the peculiar magnetic fabrics encountered in the Gubaoquan doleritic dikes and to explore their regional tectonic implications, we conducted a multidisciplinary study on 26 dikes in the southern Beishan Orogenic Belt, NW China. Rock magnetic investigations indicate that multidomain to pseudo-single-domain Ti-poor magnetite is probably the main magnetic carrier. Petrological observations affirm the magnetic carrier and the typical ophitic structure of the dikes; neither the preferred orientations of constituent minerals nor authigenic minerals are detected. Magnetic fabric analyses reveal a peculiar magnetic fabric, characterized by a predominant fabric with an aclinic SW-NE−striking magnetic lineation and a horizontal magnetic foliation, as well as a subordinate fabric comprising a horizontal SE-NW−striking magnetic lineation and a horizontal magnetic foliation. Two emplacement mechanisms are proposed to interpret the observed magnetic fabrics: (1) in near-surface conditions (<300 m), a horizontal intrusion generated the magnetic fabric that was locally disrupted by preexisting and synemplacement subfractures, and (2) at subsurface conditions (>1 km), due to the possible stress balance between overburden load and magma pressure, the vertical component of the magma flow was obscured; in such settings, the subordinate fabric may result from the propagation of cooling joints. Integrated with available geochronological, geological, geochemical, and paleomagnetic data, our findings suggest that the Gubaoquan dikes were emplaced under the influence of the Tarim mantle plume or within a postcollisional extensional setting during the early Permian.

The Nanpanjiang Basin, the largest Mesozoic depocenter in the South China Block, preserves a key sedimentary archive of the subduction and closure of the Eastern Paleo-Tethys Ocean, yet its tectonic nature and geodynamic significance remain controversial. Here we present integrated detrital zircon UPb geochronology and Hf isotope data from a continuous Middle Triassic succession to constrain basin evolution and its response to deep geodynamic processes. During the Anisian, a unimodal zircon age population centered at similar to 250 Ma indicates dominant derivation from a proximal magmatic arc and deposition in an extensional back-arc basin. By the Ladinian, the emergence of older age populations (similar to 450 Ma, similar to 1.0 Ga, and similar to 1.9-2.0 Ga) records progressive unroofing of the arc and its underlying basement, marking a transition to retro-arc compression. In the Late Triassic, the influx of abundant similar to 700-800 Ma detritus with Yangtze Block affinity indicates the onset of continental collision and development of a retro-arc foreland basin. Detrital zircon epsilon Hf(t) systematics further constrain the associated geodynamic transition. The 300-260 Ma zircons display strongly dispersed epsilon Hf(t) values (median values between -4.04 and - 3.54, the interquartile ranges of 6.93 to 9.21), consistent with substantial crust-mantle mixing in an open mantle wedge above a steeply dipping slab, whereas the 260-240 Ma zircons yield more restricted and systematically negative epsilon Hf(t) values (median values between -9.64 and - 8.54, the interquartile ranges of 2.75 to 2.76), indicating diminished mantle input and enhanced crustal reworking during slab flattening. Taken together, these sedimentary and isotopic signals indicate that the Nanpanjiang Basin records a three-stage evolution from an extensional back-arc stage through a compressional retro-arc stage to a collision-related retro-arc foreland stage, representing the sedimentary response to a transition from steep to flat subduction of the Eastern Paleo-Tethys Ocean.

Oxygen isotopic diversity of arc magmas can be used to trace their distinct sources and, in turn, shed light on material recycling during crust-mantle interaction in the subduction zone. Herein, we present new zircon O isotopes for the Neoproterozoic (ca. 820-760 Ma) mafic to felsic igneous rocks in the western Yangtze Block (South China) to understand how slab subduction imparts diverse oxygen isotope in arc magmatic rocks from the northwestern circum-Rodinia subduction system. The ca. 807-802 Ma high zircon-delta O-18 basaltic andesites to dacites display variable zircon epsilon Hf(t) (-0.37-+11.5) and high delta O-18 values (up to 7.09 parts per thousand). In combination with highly variable MgO (2.01-9.06 wt%), K2O (2.43-4.70 wt%), Rb/Y (2.99-8.98), Th/Ce (0.15-0.31), Th/Sm (1.51-3.21), Th/La (0.30-0.64) and Th/Yb (3.20-10.1) as well as negative epsilon Nd(t) (-4.22 to -0.86) values, these basaltic andesites to dacites originated from a mantle wedge source metasomatized by subducted fluids and sediment melts. The ca. 820-760 Ma low zircon-delta O-18 rhyolites and granites have elevated silicic contents (73.05-78.49 wt%), positive-dominantly epsilon Nd(t) (-0.69 to +1.99) and highly positive epsilon Hf(t) (+6.16 similar to+11.9) values as well as sub-mantle to mantle-like delta O-18 values (3.82 parts per thousand-5.58 parts per thousand), which were formed by the partial melting of juvenile mafic arc lower crust that was originally supplemented by mantle wedge melts metasomatized by hydrothermally altered oceanic crust (AOC) melts. The heterogeneous zircon delta O-18 values of igneous rocks, combined with available paleomagnetic data, indicate that the persistent peripheral subduction around Rodinia has introduced distinct metasomatized agents (i.e., subducted fluids, sediment melts, and AOC melts) into the sub-arc mantle source, which resulted in the mantle wedge heterogeneity and zircon delta O-18 diversity of Neoproterozoic arc magmatism across the western Yangtze Block (South China) in northwestern circum-Rodinia subduction system. Slab subduction is thus significant for the geochemical diversification of arc magmas and mass exchange between the mantle and crust.

As the dominant component of Earth's early continental crust, tonalite-trondhjemite-granodiorite (TTG) suites offer critical insights into the crust-mantle dynamic systems and geodynamic regime for the early Earth (>2.5 Ga). Although TTGs are generally accepted to have originated from partial melting of hydrated metabasalt, specific conditions and mechanisms remain enigmatic, which has sparked intense debate over the geodynamic settings of the early Earth. Here, we conduct thermodynamic-geochemical modellings to systematically compare the roles that pressure, bulk H2O content, and source rock composition play in shaping TTG magmas. We find that pressure is the first-order factor controlling the formation and compositional diversity of TTG. Our modellings also predict the optimal melting conditions for different types of TTGs, which are further validated by the ranges of magmatic H2O contents recorded by apatite and zircon from global TTG samples. We propose an apatite-based melt hygrometer and apply it to Archean TTGs for the first time. Combined with the results from the zircon hygrometer, our data show that high-pressure TTGs have the highest H2O contents (7 – 12 wt.%), whereas the low-pressure TTGs have the lowest (4 – 7 wt.%), matching our prediction of the optimal H2O contents for TTG melts. We show that high-pressure TTG is likely derived from fluid-fluxed melting at subcrustal depths (14 – 16 kbar), a process readily explained by subduction rather than intraplate crustal formation models. Furthermore, the temporal and spatial distribution of both high-pressure TTGs and arc-like basalts points to subduction that likely started as a localized phenomenon and transitioned to a global-scale process at about 3.0 Ga.

A new gem‐quality zircon reference material, S513, was developed for in situ microbeam U‐Th‐Pb, (U‐Th)/He geochronology and Hf‐O isotope measurement. The well‐cut gem‐quality zircon weighed 51.3 carats. Its U, Th, Pb and Hf mass fractions were 924 ± 64.6 μg g −1 (2 s ), 89.6 ± 3.92 μg g −1 (2 s ), 119 ± 5.20 μg g −1 (2 s ) and 8259 ± 244 μg g −1 (2 s ), respectively. Imaging results from LA‐ICP‐ToF‐MS analysis showed homogeneous distribution of elements in S513. The Th‐corrected weighted mean 206 Pb/ 238 U, 207 Pb/ 235 U and 207 Pb/ 206 Pb ratios of S513 zircon from eight ID‐TIMS analyses are 0.090955 ± 0.000019 (2 s , MSWD = 0.22, n = 8), 0.73873 ± 0.00023 (2 s , MSWD = 0.19, n = 8) and 0.058934 ± 0.000008 (2 s , MSWD = 0.35, n = 8), respectively. The Th‐corrected weighted mean 206 Pb/ 238 U age obtained from chemical abrasion‐isotope dilution‐thermal ionisation mass spectrometry is 561.18 ± 0.63 Ma ( n = 8, 95% conf., MSWD = 0.9), which is recommended as the best age estimate of S513. The weighted mean 206 Pb/ 238 U ages obtained from in situ microbeam analysis (i.e., LA‐ICP‐MS and SIMS) were 560.8 ± 5.8/10.2 Ma (2 s , n = 260) and 562.4 ± 7.2/13.4 Ma (2 s , n = 198). The measured weighted mean 208 Pb/ 232 Th age of S513 from LA analyses was 561.3 ± 3.3/11.7 Ma (2 s , n = 86). The U‐Pb and Th‐Pb ages of S513 obtained with in situ methods showed good agreement with the CA‐ID‐TIMS results, respectively. The obtained (U‐Th)/He age of S513 from thirty‐seven aliquots analysed with U‐Th isotope dilution method was 420.3 ± 7.6 Ma (2 s , MSWD = 0.72). The recommended reference value of Hf isotope ratio was 0.281606 ± 0.000010 (2 s , MSWD = 1.4, n = 12) according to the mean 176 Hf/ 177 Hf ratio acquired with solution MC‐ICP‐MS analysis. All the LA analyses yielded a mean 176 Hf/ 177 Hf ratio of 0.281605 ± 0.000008 (2 s , MSWD = 0.53, n = 310), which was consistent with the reference value. Laser fluorination analyses yielded mean δ 18 O values of S513 were 11.71 ± 0.11‰ (2 s , MSWD = 0.25, n = 5). The results obtained with multiple analytical methods show that zircon S513 is homogeneous to 8% (1 s ) or better for contents of Y, Nb, Ce, Gd, heavy REE, Ta, U, Th, Pb and Hf. Additionally, the homogeneity is observed at 0.12‰ (2 s ) for U‐Pb ages, 1.8% (2 s ) for (U‐Th)/He ages, 0.0036% (2 s ) for Hf isotopes, and 0.11‰ (2 s ) for O isotope ratios. Zircon S513 is proposed as a new potential primary calibration or quality control reference material for microbeam U‐Th‐Pb geochronology and Hf‐O isotope measurement.

The Panjal, Rajmahal–Sylhet, and Deccan Traps in India constitute voluminous flood basalt provinces emplaced under distinct tectono-magmatic regimes. The formation of Panjal Traps (∼289 Ma) is attributed to extensional tectonic processes—specifically lithospheric thinning and decompression melting of the lithospheric mantle domains associated with rifting of the Cimmerian terranes and opening of the Neo-Tethys Ocean, whereas the Rajmahal–Sylhet (∼117 Ma) and Deccan (∼66 Ma) Traps are considered to represent mantle plume-related large igneous provinces (LIPs) associated with the Kerguelen and Réunion hotspots, respectively. Using the most primitive basalt compositions, we constrained mantle potential temperatures (Tp), source lithologies, and melting depths of these spatially and temporally distinct provinces. The Panjal basalts yield Tp of 1379–1470 °C, with onset of melting at ∼81 km depth. The Rajmahal–Sylhet and Deccan basalts exhibit elevated Tp (1545–1639 °C and 1519–1556 °C), with melting initiated at depths of ∼177 km (Rajmahal–Sylhet) and ∼ 132 km (Deccan), respectively. Peridotite versus pyroxenite melting models suggest that plume-derived LIPs are best explained by the melting of hydrous peridotite sources. Pyroxenites are likely restricted to lithospheric mantle domains and are not intrinsic to deep mantle plume sources. The rapid increase in root mean square (RMS) plate velocities of India during the post-Pangean period are correlated with the spatio-temporally associated Mesozoic LIP events. This suggests that mantle plumes likely played a key role in accelerating India's motion by enhancing the influence of far-field plate boundary forces, possibly through thermomechanical erosion of the cratonic keel beneath the Indian plate.

Carbonatites are critical carriers of carbon and potential reservoirs of rare earth elements, which provide valuable insights into probing Earth's deep processes. Recent studies have identified carbonatitic melts derived from the partial melting of sedimentary carbonates in Phanerozoic subduction zones. However, whether such carbonatites could be formed in Precambrian settings remains unclear due to high mantle temperatures and uncertain Archean-Paleoproterozoic tectonic dynamics. In this study, we sampled Paleoproterozoic carbonatites from the southeastern Tarim craton, northwest China, and conducted geochemical, isotopic, and geochronological analyses to elucidate their petrogenesis. Zircon and apatite U-Pb ages indicate carbonatite crystallization occurred at ca. 1.87 to 1.83 Ga, and mineral chemistry points to mantle depths of melt generation. However, the Tarim carbonatites have trace element patterns comparable with sedimentary carbonates and Sr-Nd isotopes (87Sr/86Sri = 0.704-0.706; 143Nd/144Ndi = 0.509895-0.510052) differing from those of mantle-derived carbonatites. In addition, their C-O isotopes (delta 13CPDB = 11.78-14.32 parts per thousand; delta 18OSMOW = 14.83-15.97 parts per thousand) resemble the extents of marine carbonates, which were deposited in the Lomagundi-Jatuli Event (ca. 2.3-2.0 Ga). Hence, we propose that the Tarim carbonatites originated from partial melting of subducted Lomagundi-Jatuli Event carbonates at mantle depths. Our findings provide the earliest evidence for carbonatites derived from subducted sedimentary carbon, hinting that carbon recycling at the crust-mantle scale has been operative as early as the Paleoproterozoic.

Rare metal deposits are clearly related to highly evolved granites. The Limu LiF granite complex hosts early quartz vein-hosted WSn ore and late stage disseminated Ta-Nb-Sn +/- W ore. To elucidate unique characteristics of cassiterite from Ta-Nb-Sn-W ore-forming system and the link between magmatic evolution and NbTa mineralization, we analyzed textures and trace element compositions of cassiterites from both ore types, and conducted LA-ICP-MS UPb dating on cassiterites and columbite group minerals (CGMs). Both vein and disseminated cassiterites exhibit low Fe and high (Nb + Ta) contents with molar (Nb + Ta)/Fe ratios (>7), significantly exceeding those of typical Sn-granite cassiterites (<2). Late disseminated cassiterite displays high Nb and Ta oscillatory zoning eroded by low NbTa domains, and intergrows with CGMs indicating a dissolution-reprecipitation process via hydrosilicate liquid during crystallization. Contrastingly, low and constant Zr/Hf (similar to 4) suggest Zr and Hf remain stable in the hydrosilicate liquid. We proposed that high molar (Nb + Ta)/Fe ratios and eroded structures in cassiterites may indicate the potential NbTa ore. Early quartz-vein cassiterites yielded ages of 215.5 +/- 3.5 Ma, while late disseminated ores produced ages of 214.3 +/- 2.4 Ma (cassiterite) and 212.7 +/- 1.1 Ma (CGMs). Combined with previous zircon ages from early-stage granite (230-227 Ma), the Limu magmatic-hydrothermal system spans 15-16 Myrs. This long-lived magmatic-hydrothermal system depleted in Fe and enriched in (Nb + Ta), driven by continuous mantle-derived heat, likely underwent early fluid exsolution, triggering quartz vein WSn ores, followed by further melt evolution forming Nb-Ta-rich hydrosilicate liquid, which we consider a prerequisite for NbTa enrichment and evolved to generate the late disseminated Ta-Nb-Sn +/- W ore.

Tonalite-trondhjemite-granodiorite suites, dominating Earth’s early continental crust, likely formed by partial melting of hydrated metabasalt, but the specific conditions and mechanisms remain poorly constrained. Here, we conduct thermodynamic-geochemical modeling to systematically compare the roles that pressure, bulk H2O content, and source rock composition play in shaping these ancient rocks. Accordingly, we assess their optimal forming conditions, which are further validated by magmatic H2O contents retrieved from the apatite and zircon crystals of tonalite-trondhjemite-granodiorite suites. Our results highlight that pressure is the first-order factor controlling the formation and compositional diversity of these rock suites. Those with “high-pressure” geochemical characteristics are derived from fluid-fluxed melting at 14 – 16 kbar, a process readily explained by subduction rather than intraplate geodynamic regime. Furthermore, the temporal and spatial distributions of “high-pressure” variants, coupled with those of arc-like basalts, suggest subduction that likely initiated as a local phenomenon and transitioned to a global-scale process by 3.0 Ga. Pressure plays a primary role in controlling the formation and compositional diversity of tonalite-trondhjemite-granodiorite suites, with “high-pressure” variants derived from fluid-fluxed melting during subduction, recording the onset of global subduction at ~3.0 Ga, according to thermodynamic-geochemical modeling and mineral hygrometry analysis.