The proposal of novel theoretical ideas in Earth history such as plate tectonics and Darwinian life evolution has led to great leaps forward in the disciplinary development of geosciences. The rapid development of Earth-systems science in modern days has allowed integration of interactions among the Earth spheres and comparison at a range of time scales, favoring the development of novel theories. Comparison of geological events at different time scales is of particular importance. In modern days, changes in the Earth system are occurring at an unprecedented rate, in particular, a rapid increase in atmospheric CO2 concentrations and declines in biodiversity. Although not comparable in amplitude with changes observed in deep time, modern changes clearly exceed them in the rate. This indicates that rates of variation in the carbon cycle and biodiversity in deep time are critical to understanding the trajectory of global changes in modern days and their consequences. However, it is a grand challenge to investigate rates of geological events in deep time due to generally low temporal resolution and unavailability of reliable proxies for some paleoclimatic and paleoenvironmental factors. Consequently, the causal relationships of life to environments in Earth history have been investigated mainly on the basis of the amplitudes of geological and biological events. To address this knowledge gap in rates of processes between the deep time and modern records, it is necessary and important to conduct multidisciplinary studies. It is notable that the rapid development of isotopic geochronological dating techniques has greatly enhanced precision dating of past events, and that big data analysis of paleontological records, high-resolution stratigraphic correlations, and astrochronological techniques have contributed to improvements in the dating resolution of ancient events by an order of magnitude or better, presently yielding dates with an accuracy to tens of thousands of years that can provide a robust high-resolution geochronological framework for geochemical, isotopic, and lipid biomarker studies. In addition to the dating issue, it is of significance to propose novel proxies for paleoenvironmental analysis and to develop numerical simulation techniques suitable for reconstruction of interactions among Earth-system spheres in deep-time systems. Large models with the aid of artificial intelligence are likely to become important tools for qualitative evaluation of causal relationships between the carbon cycle and biotic events on the basis of intrinsic rates of variation. Preliminary studies were conducted in recent years on rates of variation of geological events such as the Big Five mass extinctions of the Phanerozoic, but these investigations were conducted at low (ca. million-year) temporal resolutions that are incompatible with rates of modern changes. It will be essential to achieve temporal resolutions on the millennial scale in order to undertake accurate comparisons between ancient and modern changes in the global carbon cycle and biodiversity. The data gained through high-resolution studies of deep-time systems will enable us to bridge observational and theoretical gaps in knowledge between the modern and ancient Earth systems as well as to better achieve a more holistic understanding of interactions among its spheres, stimulating a transformative advance of interdisciplinary Earth-systems research.

The radiometric ages of the returned samples are the cornerstone of lunar cratering chronology models. However, all the previous samples were from the lunar nearside and the radiometric ages of those samples that can be associated with particular surfaces are <4.0 billion years. On 25 June 2024, Chang'e-6 successfully returned 1.935-kilogram samples from the lunar farside. The samples included local basalts with an age of 2807 ± 3 million years and the norites with an age of 4247 ± 5 million years likely corresponding to the age of the South Pole-Aitken basin. With these radiometric ages, we refined the lunar chronology function (CF) and verified that it is still consistent with a combination of an exponential decrease and a linear rate. We further derived the impacting rate and found it supports a smooth decay instead of abrupt changes of the impactor flux at early times. The refined lunar CF can be used to obtain more reliable ages for unsampled lunar areas and provide critical constraint for the lunar early impact history.

The complex Arabia-Eurasia plate interaction triggered Jurassic-Cretaceous orogenic magmatism within the Sanandaj-Sirjan Zone, the core of the Zagros orogen in Iran. While subduction-related magmatism is expected near convergent margins, the geodynamic mechanisms responsible for Early Cretaceous alkaline magmatism in the Sanandaj-Sirjan Zone remain unresolved. To address this gap, we present new geochronological and geochemical data from a unique suite of lower Cretaceous alkaline magmatic rocks within the composite Cheshmeh-Sefid syenite-gabbroic pluton, located in the southwestern Golpaygan Complex of the central Sanandaj-Sirjan Zone. High-precision zircon U-Pb geochronology using secondary ion mass spectrometry (SIMS) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) reveals emplacement ages of 128 +/- 1 Ma for both syenite and gabbro, 127 +/- 0.92 Ma for syenite, and 125 +/- 0.9 Ma and 125 +/- 1.3 Ma for isolated mafic and felsic dikes. Zircon Hf-O isotope compositions exhibit limited variability, with epsilon Hf(t) values of +4.1 to +11.4 and delta 18O values averaging +4.93 parts per thousand to +5.44 parts per thousand. Coupled trace element and isotopic data indicate that the parental magmas originated from low-degree partial melting of a metasomatized subcontinental lithospheric mantle (SCLM) source, characterized by spinel +/- minor garnet, followed by fractional crystallization with neg ligible crustal assimilation. We propose that this distinct episode of Early Cretaceous alkaline magmatism across the Sanandaj-Sirjan Zone resulted from lithospheric extension following the cessation of flat-slab subduction, likely triggered by oceanward trench retreat that induced decompression melting above an upwelling asthenospheric mantle wedge.

A comprehensive investigation was conducted on high-hafnium zircons from the LCT (Li-Cs-Ta) pegmatites of the Vasin-Mylk rare-metal deposit within the Fennoscandian Shield. In situ analysis of trace element composition and oxygen isotope ratios were performed using secondary ion mass spectrometry (SIMS), complemented by internal structural examination via scanning electron microscopy (SEM). The research focuses on deciphering compositional zoning within zircon crystals and characterizing their geochemical signatures to constrain crystallization conditions. The study revealed anomalously high concentrations of Hf (up to 381,000 ppm) and Li (up to 152 ppm), paired with extremely low abundances of U (~10 ppm) and total rare earth elements (~35 ppm). Marked geochemical contrasts were identified between the central and rim domains of the zircons. Central zones display well-fractionated rare earth element (REE) patterns featuring positive Ce and negative Eu anomalies, while the high-Hf rims exhibit weakly differentiated spectra with variable Ce anomalies. The identified W-type tetrad effect suggests crystallization from a melt strongly influenced by coexisting fluids. The obtained δ18O values are consistent with a mantle source and suggest crystallization within a system closed to external fluids. The zircons from the Vasin-Mylk deposit crystallized during the transitional period between the late magmatic and early hydrothermal stages of a highly differentiated pegmatite system. These results contribute to a better understanding of ore genesis in LCT pegmatite systems.

Dharwar Craton in South India, offers important insights into the crustal evolution history of the Neoarchaean. This study investigates the tectonic evolution of granitoids adjacent to the central part of the Hungund greenstone belt, northernmost part of the Eastern Dharwar craton through a multidisciplinary approach involving field investigation, petrographic studies, whole rock geochemistry along with zircon mineral chemistry and U-Pb zircon ages of biotite granites and sanukitoids. The biotite granite from eastern parts of the belt are 2595-2607 Ma, show peraluminous to metaluminous characteristics; Mg# ranging from 17 to 30 with a distinct negative Eu/ Eu* of 0.06-0.33, high Rb/Sr (avg. 3.96) and low Sr/Y (avg. 5.50) ratios suggesting their generation by partial melting of tonalite-trondhjemite granodiorite (TTG) in the continental margin arc settings. Trace element compositions of zircons from the dated granites corroborate their continental crustal-derived magma in arc setting. The sanukitoids, on the other hand, are metaluminous, with comparatively higher Mg# (28-40), mild Eu/Eu*0.36-0.59, low Rb/Sr (avg. 0.22) and high Sr/Y (avg. 47.31) ratios originated from a mix of crustal and mantle derived components. In view of differences in their geochemical characteristics, mode of origin and ages, they are considered to have a distinct petrogenetic and tectonic history, amalgamated during accretionary event. Integration of the present work with the data from various continents reveal that cratonic evolution through amalgamation of microcrustal block was a global phenomenon during the Neoarchaean.

Deciphering the composition and evolution of Earth's earliest continental crust commonly relies on reconstructing parental-melt rare earth element (REE) signatures from Hadean zircons. This approach is highly sensitive to zircon-melt REE partition coefficients (DREE). However, published zircon DREE values span orders of magnitude, leading to divergent and sometimes contradictory inferences about early crustal compositions. A major cause of this inconsistency is the lack of rigorous criteria for assessing the reliability of natural zircon DREE. Here, we compile a global dataset of natural zircon/bulk-rock pairs and adopt the lattice-strain-based delta K deviation index of Zou et al. (2019) to screen for robust DREE. Using the screened dataset, we establish recommended DREE envelopes for high-SiO2 and low-SiO2 natural systems. We evaluate recommended high-SiO2 envelope with DREE estimated from different zircon generations within the Acasta Gneiss Complex. The earliest igneous zircon population yields DREE values that fall largely within this envelope, supporting its applicability to ancient felsic zircon-forming systems. Finally, we apply the recommended high-SiO2 DREE envelope to reconstruct parentalmelt REE patterns for detrital zircons from Jack Hills, Green Sandstone Bed, and Singhbhum Craton. The resulting REE signatures are most consistent with incompatible-element-enriched granitoid compositions than with TTG, Acasta-like, or Icelandic analogues. This integrated mineral-physics and big-data workflow reduces longstanding uncertainty in zircon DREE selection and provides a broadly applicable strategy for constraining plausible partition coefficients across mineral-magma systems.

Spinel, a key mineral in mafic-ultramafic rocks, is highly sensitive to petrologic and geochemical processes. The oxygen isotopic composition of spinel provides valuable insights into diverse geological processes, for which accurate and precise in situ analysis is a fundamental requirement. A major challenge for microanalytical techniques, such as secondary ion mass spectrometry (SIMS), is the scarcity of matrix-matched reference materials for correcting instrumental mass fractionation and monitoring analytical accuracy. Here, we report three new working reference materials for in situ oxygen isotopic analysis: MadSP (Mg0.75Fe0.25Al2O4), a Madagascar black spinel, TanzSP-1 and TanzSP-2, both of which are nearly pure Mg spinels from Tanzania. SIMS analyses show that they have homogeneous oxygen isotopic compositions, with a two-standard deviation of 0.37 parts per thousand (N = 105), 0.40 parts per thousand (N = 106), and 0.33 parts per thousand (N = 106), respectively. Laser fluorination isotope ratio mass spectrometry (IRMS) yields delta 18O values of 11.94 +/- 0.43 parts per thousand for MadSP (2SD, N = 5), 23.40 +/- 0.20 parts per thousand for TanzSP-1 (2SD, N = 4), and 13.29 +/- 0.48 parts per thousand for TanzSP-2 (2SD, N = 6). Our results show that there are no significant matrix effects for magnesia-alumina spinels with Fe2+ ranging from 0% to 25%.

The formation and evolution of the Archaean continental crust record the history of the early Earth, although its magmatic sources and magmatic environments remain controversial. Detrital zircons may preserve geochemical signatures of both extinct and surviving crustal rocks, providing insights into crustal formation. We present in situ Si-O isotope and trace element data for detrital zircons from Caozhuang (3.84-3.53 Ga) and Kaapvaal (3.55-3.45 Ga and 3.28-3.11 Ga). The zircons have delta 30Si values of -0.50%o to -0.12%o, corresponding to modeled melt delta 30Si values that are higher than those of the Igneous Array. The 3.84-3.53 Ga Caozhuang and 3.26-3.11 Ga Kaapvaal zircons display elevated delta 18O values (6.03-7.25%o) compared to mantle zircons, whereas those from 3.55 to 3.45 Ga and one 3.28 Ga Kaapvaal zircons display "mantle-like" delta 18O signatures (5.49-6.05%o). Consistently high delta 30Si values in the zircons indicate a contribution from supracrustal silicified materials. This suggests that the "mantle-like" delta 18O values may not necessarily reflect a mantle source. Instead, these delta 18O signatures may result from metasomatism of the source by low-delta 18O fluids derived from komatiites, or may reflect the limited sensitivity of O isotopes to trace supracrustal materials in ancient zircons. By combing the Si-O isotopes of zircons with their Tht/Nb (16-157) and Ut/Nb (50-417) ratios, Dy/Yb ratios (0.2-0.4), we suggest that the parent melt of zircons have geochemical affinities to arc magmas. Compared to Jack Hills zircons, the absence of pelitic material and meteoric water signatures suggests that these zircons were formed far from subaerial continents.

The Bayan Obo deposit in China is the largest light rare earth element (LREE) deposit worldwide, and also hosts substantial Nb and heavy REE (HREE) resources. However, the timing and enrichment mechanisms of the Nb and HREE mineralization are poorly constrained. Aeschynite is the most important Nb- and HREE-bearing mineral at Bayan Obo and was investigated in this study to reconstruct the history of Nb and HREE mineralization. In situ Lu–Hf isochron dating of two types of aeschynite yielded consistent ages of 435–420 Ma, which overlap with the Th–Pb isotopic ages of intergrown monazite (438–392 Ma). These results demonstrate that early Paleozoic is a significant episode for Nb and HREE mineralization. The aeschynite has a close spatiotemporal relationship with alkali silicates, suggesting that hydrothermal fluids were naturally rich in alkalis and dominantly exsolved from coeval carbonatitic magmas. Strontium isotopic compositions of aeschynite are relatively enriched and exhibit an increased trend from the type-1 (87Sr/86Sr = 0.7037–0.7064) to type-2 (87Sr/86Sr = 0.7072–0.7128), which was likely caused by heterogeneous crustal contamination during the evolution of hydrothermal fluids. Paragenetic aeschynite, calcite, fluorite and bastnäsite reflect that carbonate (CO32–) and fluoride (F−) anions played a key role for Nb mobilization. The unloading of Nb in aeschynite was usually related to the variation of Ti content in hydrothermal fluids. According to apparent correlation of REE, Th and Ca in aeschynite and developed ilmenite, Nb unloading was influenced by the processes of coupled substitution or ilmenite crystallization. The enrichment of HREE was ascribed to preferential LREE fractionation following gradual temperature decrease of CO32–-bearing alkaline hydrothermal fluids. Moreover, earlier crystallized LREE minerals is potential trigger for local elevation of HREE content.

Asteroid impact, playing a key role in shaping the Moon, is a consequence of the orbital dynamical evolution of the Solar System. While the impact flux can be deduced from lunar craters, the impactor populations and their temporal variations remain poorly understood. We analyzed Fe-Ni metals in 40 impact clasts from the Chang'e-6 lunar soils and demonstrated that most of them are asteroidal remnants. The majority of these clasts (27 out of 40) originated from local basalt, where the asteroidal materials were accumulated after basaltic eruption at 2.8 billion years ago (Ga). The remaining 13 clasts are exotic feldspathic materials, delivered from the ancient lunar highlands, preserving asteroid remnants from similar to 4.3 Ga to the present. By classifying the asteroid impactors based on the Ni, Co, P, Ir, and Au contents of the metals, we identified distinct impactor populations for the two clast types. All carbonaceous chondrite metals are exclusively found in seven of the basaltic impact clasts, providing robust evidence for a late-stage bombardment by carbonaceous asteroids. The significant increase in carbonaceous impactors can be attributed to orbital dynamical events between 4.3 and 2.8 Ga, including giant planet migration, the Yarkovsky effect, or breakup of large carbonaceous asteroids. These findings, together with the exponentially declining impact flux, imply that only a small proportion of carbonaceous asteroids were delivered to the early Earth-Moon system, and provide further constraints on the dynamical evolution of the Solar System. Plain LanguageSummaryThe orbitaldynamicevolutionof the Solar Systemis criticalto Earth'shabitabilityand is largelyconstrainedby impactfluxesrecordedin lunar craters.However,the distributionofasteroidimpactortypes-anotherkey parameter-remainspoorlyunderstood.Here, we analyzedindividualiron-nickelmetal grainsin the Chang'e-6impactclasts from two regionsof differentages, to trace possiblechangesin the types of asteroidimpactors.The data reveala significantincreasein the relativeabundanceofcarbonaceousasteroidimpactorsbetween similar to 4.3 and similar to 2.8 Ga. These findingsshed light on the orbitaldynamicsof the early Solar System,and the late bombardmentof carbonaceousasteroidshas importantimplicationsforthe deliveryof water to the early Earth.

Abstract The increased demand for rare earth elements (REE) associated with the global transition to low-carbon energy systems requires the development of new exploration tools. Lichens, symbiotic associations of fungi and algae or cyanobacteria, represent promising biological indicators in mineral exploration owing to their visibility, substrate specificity, and environmental resilience. Through detailed field mapping and preliminary geochemical investigations in the Bayan Obo deposit, we identified that the lichen Xanthoria elegans selectively grows on REE-enriched carbonatites. This lichen contains exceptionally high REE concentrations (ΣREE = 3,500–17,000 ppm), which correlate closely with the REE contents of its substrates. It also exhibits Sr and Pb isotope compositions indistinguishable from those of its host carbonatites. The strong spatial and chemical affinity of X. elegans for carbonatites, combined with its scarcity on other lithologies, supports it as a reliable and effective field indicator in this region and its potential in analogous environments elsewhere. When integrated with remote-sensing techniques, this new biological proxy could offer a rapid, low-cost, and environmentally friendly means to detect REE-bearing carbonatites, offering a valuable complement to traditional exploration strategies.

Abstract Bayanoboite-(Y) (IMA2023-084), Ba2Y(CO3)2F3, is a new mineral discovered at the Bayan Obo deposit in Baotou City, Inner Mongolia, China. The mineral is named after its type locality (Bayan Obo deposit) with mineral symbol “Byb-Y.” The holotype of bayanoboite-(Y) is found within a crack between sulfide grains dispersed in dolomite. The host sulfide grains are predominantly pyrite, with some regions partially transformed into pyrrhotite. Bayanoboite-(Y) is brittle with conchoidal fracture, a Mohs hardness of 4–5, and perfect cleavage along {001}. The calculated density is 4.69 g/cm3. The empirical chemical formula for the holotype is A(Ba1.94Sr0.06)Σ2.00B(Y0.77Dy0.06Gd0.04Fe0.03Ca0.02Nd0.02Er0.02Yb0.02Sm0.01)Σ1.00(CO3)2(F2.79O0.08)Σ2.87 based on (A + B)apfu = 3. Bayanoboite-(Y) is orthorhombic, space group Pbcn (#60), with unit-cell parameters a = 9.4528(4) Å, b = 6.9499(2) Å, c = 11.7638(5) Å, V = 772.83(5) Å3, and Z = 4. The crystal structure of bayanoboite-(Y) represents a novel structure type for minerals, and it is characterized by two 9-coordinated large cation sites: a Y site and a Ba site, both forming tetrakaidecahedra with surrounding O and F atoms. Bayanoboite-(Y) has a layered-framework structure composed of two distinct blocks: (1) thick slabs formed by two adjacent, oppositely oriented layers where [YO6F3] polyhedra are connected by [CO3] triangles; and (2) a framework built from [BaO5F4] polyhedra arranged as edge-shared wavy-line chains, which are further connected by F atoms and [CO3] triangles. These two blocks are well bonded through the shared edges and faces of [YO6F3] and [BaO5F4] polyhedra. In addition to Y, it also contains Gd (0.60–1.32 wt%), Dy (1.51–2.13 wt%), Er (0.51–0.85 wt%), and Yb (0.36–0.79 wt%). Therefore, the discovery of bayanoboite-(Y) holds significant implications for comprehending the occurrence of heavy rare earth elements (HREEs) in the Bayan Obo deposit. It also provides mineralogical evidence for the evolution of the Bayan Obo deposit, and this new mineral has the potential to serve as an indicator for the exploration of HREEs in this region.

Most global niobium (Nb) resources are associated with carbonatite systems and are commonly interpreted as magmatic in origin, with Nb hosted mainly by pyrochlore [(Na,Ca)(2)Nb2O6F] crystallized from carbonatitic melts. However, in parts of the giant Bayan Obo REE-Nb deposit, Nb occurs predominantly as columbite [FeNb2O6] within fenite rather than carbonatite, implying an underappreciated hydrothermal style of Nb mineralization. This study integrates mineralogical observations, geochemical analyses, and hydrothermal experiments to investigate the origin of the fenite-hosted Nb ores and to advance our understanding of Nb enrichment behavior in carbonatite-related systems. The Nb-rich fenite (up to 8216 ppm Nb) mainly contains biotite, accompanied by subordinate columbite, calcite, barite, monazite, bastnasite, and pyrite. It is enriched in fluid-mobile elements (e. g., Rb up to 297 ppm, Ba up to 17,552 ppm, and S up to 13.35 wt% as SO3), indicating its formation through intensive interaction between carbonatite-derived fluids and silicate wall rocks. Biotite Ti thermometry suggests a high temperature (> 600 degrees C) of fenitizing fluids. The mineral assemblages indicate that these fluids were enriched in K+ and CO32-, with subordinate F-. Based on these physicochemical constraints, hydrothermal diamond anvil cell (HDAC) experiments were conducted, and demonstrate that columbite can be effectively dissolved in K+-CO32--F--bearing fluids at temperatures of similar to 400-similar to 600 degrees C. In general, this study shows that carbonatite-related Nb mineralization can extend beyond the purely magmatic stage into a high-temperature hydrothermal stage, highlighting the exploration potential of fenite-hosted hydrothermal Nb resources.

How continental crust forms during subduction remain debated: does it grow through steady-state magmatism or brief, high-flux events (flare-ups)? The drivers and crustal growth potential of such flare-ups are poorly constrained. The Alborz–Azerbaijan magmatic belt in NW Iran preserves a significant Eocene flare-up, offering an ideal natural laboratory to address this question. We investigate the late Eocene Tarom plutonic bodies (TPBs) using geochemical and isotopic data to constrain their petrogenesis, quantify crustal growth, and reconstruct regional tectonic evolution. The TPBs were emplaced rapidly at ca. 40 Ma, originating from low-degree partial melts of metasomatized mantle, followed by fractional crystallization with minimal crustal contamination. This flare-up yielded a magmatic addition rate of ca. 73 km3 km−1 Myr−1, comparable to major cordilleran systems, demonstrating significant net crustal growth. Using chemical mohometry, we track crustal thickness through time: from ca. 28 km during Cretaceous rifting, to ca. 38 km during the Eocene flare-up, increasing to ca. 50 km in the Oligocene, and peaking at ca. 56–62 km in the Miocene. This trajectory reflects the transition from subduction to collision. Subsequent geochemical shifts signal slab break-off at ca. 10–12 Ma and lithospheric delamination at ca. 6 Ma, triggering renewed mantle-dominated magmatism. Our results demonstrate that the Eocene flare-up was a fundamental crust-building episode, not merely a surficial volcanic event. By quantifying magma production and crustal thickening, we provide a robust framework linking plate convergence, deep mantle processes, and crustal evolution, with broad implications for understanding collisional orogens worldwide.

The North China Craton (NCC) is currently the only craton worldwide that has been unequivocally recognized as having undergone significant destruction, yet the initial time of this destruction remains debated. To address this key issue, we focus on three plutons: the Late Permian Longwangmiao pluton (262260 Ma), the Farly-Middle Triassic Huanghuading pluton (249-243Ma), and the Early Late Triassic Yunwushan pluton (238-232 Ma). Based on structural observations, anisotropy of magnetic susceptibility (AMS) and gravity modeling, we constrain the regional tectonics during pluton emplacement. Our study shows that the Longwangmiao pluton was emplaced under localized coaxial strain in the strike-slip setting. The Huanghuading pluton records magma ascent along a major E-W trending dextral strike-slip shear zone, indicating emplacement in the regional strike-slip setting. The Yunwushan pluton is more complex, i. e, the magnetic fabrics in the northern and southern parts (238-236Ma) record the influence of the Fengning-Longhua shear zone since they are consistent with each other, whereas the central part (233-232 Ma) records the coaxial strain-dominated traespression. Combining previous geochronological data from the Fengning-Longhua shear zone (255-232 Ma), we suggest that from the Late Permian to the early Late Triassic the northern NCC was dominated by E-W trending dextral strike-slip deformation, as part of the eastern segment of the Intra-Pangea Megashear. In contrast, the large number of Late Triassic (226-208 Ma) magmatic domes, syn-tectonic plutons, metamorphic core complexes, and graben or half-graben basins in the northern NCC indicate an upper-crustal extensional setting related to deep lithospheric thinning during the NCC destruction. To sum up, the evidence suggests that the northem NCC was still in E-W trending strike-slip tectonics at ca. 232 Ma, but had changed to NE-SW trending extension al ca 226 Ma. This change marks the time when the effects of craton destruction along the northern and eastern margins of the NCC began to significantly propagale into the continental interior, thereby constraining the initiation of NCC destruction to around 230Ma.