Driven by the thrust-nappe movement of the southern Longmenshan Orogenic Belt and the lateral extrusion of the Chuandian Block, seismicity within the southern Sichuan Basin (SCB) has recently intensified, coinciding with frequent industrial operations. The 2019 M⩾5 earthquakes near Weiyuan ignited intense debate concerning their genesis. To elucidate the upper crustal deformation characteristics and seismotectonic setting of the southern SCB, we deployed a dense seismic array spanning approximately 320 km and employed ambient noise tomography to invert the shear-wave velocity structure. Results reveal that the ∼2.7 km/s velocity contour closely tracks a Triassic detachment layer controlling tectonic decoupling, strongly supporting a layered deformation model. Above this contour, two distinct low-velocity zones demonstrate that the Pujiang-Xinjin and Longquanshan faults terminate within the shallow detachment layer, whereas the Luoquanjing and Changyan faults near the Weiyuan Anticline extend vertically to depths of ⩽2 km. Beneath this interface, both sedimentary strata and the crystalline basement exhibit a consistent westward-dipping wedge-shaped deformation pattern. A pronounced granite-dominated basement uplift is identified beneath the Weiyuan Anticline, whose formation is intimately linked to extensive magmatism within the Upper Yangtze Craton during the Mid-Late Neoproterozoic. During the Indosinian orogeny, this basement shortened synchronously with the overlying sediments, responding to the uplift of the Longmenshan Mountains. In the Himalayan period, the basement likely experienced renewed uplift driven by the intense thrusting of the Longmenshan Orogeny, accompanied by intense folding of the cover strata, ultimately producing the surface anticlinal topography. Currently, this basement uplift combined with overlying strata folding functions as a structural barrier, impeding and absorbing eastward-propagating tectonic stress from the Longmenshan Mountains. This process likely causes residual stress to accumulate near the Weiyuan area, creating a geodynamic setting conducive to its regional seismicity.
Characterizing the in-situ distribution of fluids within crustal rocks is a fundamental challenge, as changes in external conditions and conventional analysis can introduce significant artifacts. Shale oil systems provide a critical example where post-retrieval alteration has obscured the primary controls on hydrocarbon storage. Here, we present an integrated cryogenic workflow employing cryo-focused ion beam scanning electron microscopy (Cryo-FIB-SEM) to examine pressure-preserved organic-rich shale cores, enabling direct visualization of microscale fluid migration phenomena during the simulated transition from subsurface conditions (fresh samples rapidly frozen at −150 °C) to surface conditions (+25 °C). Our results provide direct, time-resolved evidence of hydrocarbon redistribution. In-situ, immature heavy oil is predominantly hosted and immobilized within solid organic matter. Upon warming to ambient conditions, we observe significant micro-migration of hydrocarbons into inorganic mineral domains (clays and quartz), accompanied by the volatilization of light components (C4–C8). Room-temperature SEM induces pervasive artifacts, including the collapse of organic pore networks and the formation of new fractures at organic-quartz interfaces (approximately 27
The Huichang-Xunwu area in southern Jiangxi Province features many hot springs and concealed high-heat-producing plutons. This makes the area promising for geothermal resource development. The distribution of faults and basins is critical for understanding the heat-generation mechanisms and hydrothermal fluid circulation pathways within the geothermal system. However, the paucity of permanent seismic stations in the area renders it challenging to obtain high resolution velocity structures and to accurately identify the principal geological features controlling the geothermal system. To further elucidate the role of faults and basins, this study used a dense portable seismic array, integrated ground and satellite gravity observations, and applied a joint inversion approach to invert shallow S-wave velocity structures. The results indicate that velocity anomalies delineate the region’s main geological features. Low velocity anomalies are found in the shallow centers of basins, while high velocity anomalies correspond to granitic areas in the mountains. These anomalies follow the S-shaped Shaowu-Heyuan Fault Zone, revealing that this fault zone exerts a key control on basin development. S-wave velocity, velocity perturbation, and vertical gradient profiles indicate that the Huichang basin attains a thickness of 2–4 km, with a well-preserved sedimentary cover overlying Late Yanshanian granites with high heat production rates, providing a favorable environment for deep hot dry rock (HDR) resources. Most shallow geothermal hot springs are located along extensional or transtensional fault zones. Fault zones near the basins are characterized by relatively low velocities, which likely act as pathways for geothermal fluids. These results suggest that the Huichang-Xunwu area has a favorable geothermal reservoir structure and exploration potential. However, the complex fault architecture in the study area requires further constraints from multidisciplinary data, such as electromagnetic surveys and drilling, to fully understand the genesis of the geothermal system.
The submesoscale processes are the key to transforming the energy from the mesoscale processes to the small-scale turbulent dissipation and impacting the properties of the upper mixed layer. The applicability of the turbulent thermal wind (TTW) theory to the filamentolysis and filamentogenesis of a submesoscale warm filament is investigated by a non-hydrostatic large eddy simulation model. The filamentolysis and frontogenesis of the warm filament with thermal convective turbulence are simulated in this study. The results show that a two-cell secondary circulation in the cross-filament plane may be activated by the warm filament and the turbulent vertical momentum flux. The Coriolis effect induces a change in the direction of the secondary circulations during one inertial period, which creates the conversion between the filamentolysis and the filamentogenesis of the warm filament. The along-filament vertical momentum flux enhances and weakens the secondary circulations of the filament filamentolysis and filamentogenesis. This results in the filament filamentolysis being stronger than the filament filamentogenesis. The periodic variation in the intensity of the along-filament currents is modulated by the Coriolis effect, and the cross-filament vertical momentum flux always weakens the along-filament currents. Thus, the warm filament filamentolysis obeys the TTW theory, but the warm filament filamentogenesis violates the TTW theory.
The kerogen hydrocarbon generation theory and coal-derived gas theory constitute two foundational theoretical frameworks in petroleum geology, providing key insights into the material basis and driving mechanisms of hydrocarbon generation from organic matter in sedimentary basins during thermal evolution. The development of these theories has not only advanced the understanding of hydrocarbon generation and accumulation processes, but has also provided an important theoretical basis for natural gas exploration and resource assessment in China. This study examines the evolution of kerogen hydrocarbon generation and coal-derived gas theories, with particular emphasis on the gas generation mechanisms of coal-bearing strata and their applications in natural gas exploration in China. On this basis, it systematically summarizes the regional distribution characteristics of China’s natural gas resources, highlighting source–seal coupling as a key control on the formation of large gas fields and late-stage accumulation as a decisive factor governing the degree of gas enrichment. It further elucidates the differential distribution patterns of natural gas between eastern Cenozoic tectonic basins and stable cratonic basins in central and western China. In addition, the development potential of conventional and unconventional natural gas in major basins, including the Tarim, Ordos, Sichuan, and northern South China Sea basins, is discussed. From the perspectives of theoretical development and exploration practice, kerogen hydrocarbon generation theory and coal-derived gas theory will continue to support the exploration and development of deep, ultra-deep, and unconventional natural gas in China, while providing an important theoretical foundation for the high-quality development of the natural gas industry and the transition of the national energy structure.
Knowledge of how climate change and human activities have influenced vegetation dynamics on the Tibetan Plateau (TP) is essential for promoting ecosystem sustainability and predicting the potential impacts of future global climate change. In this study, pollen records from Muricuo Lake on the eastern TP were utilized to quantitatively reconstruct the cover of individual plant taxa since ∼6800 cal yr BP by integrating the Gradient Boosted Regression Tree (GBRT) algorithm with Landscape Reconstruction Algorithms (LRAs). Overall, the vegetation cover around Muricuo Lake remained relatively stable over the past ∼6800 yr, characterized by persistently high grass cover (50
Nitrous oxide (N2O), a potent greenhouse gas with substantial climate and ozone depletion impacts, remains poorly quantified in China’s lakes and reservoirs. This study provides a first long-term (2000–2023) high-resolution national assessment of N2O emissions from lakes and reservoirs across China using machine learning driven by climate change, anthropogenic activities, soil properties, and land cover. Total national emissions declined from 19.84 to 17.87 Gg N yr−1 (2000–2016) before stabilizing during 2016–2023. Divergent trajectories were observed in reservoirs and lakes: reservoir emissions declined by approximately 6
In late July 2025, North China experienced a record-breaking persistent extreme rainfall event, triggering devastating floods and landslides that affected nearly one million people. This study demonstrates the pivotal role of the mid-latitude quasi-biweekly variability over Eurasia in driving and predicting this extreme event. A scale-decomposed moisture budget analysis first reveals that the preceding moisture accumulation due to the horizontal advection of background moisture field by quasi-biweekly low-level southerly perturbations was indispensable for the development of extreme rainfall. These southerly perturbations were attributed to the northwestward extension of the western North Pacific subtropical high induced jointly by the mid-latitude and tropical variabilities. While in the peak stage, the persistent heavy rainfall was primarily triggered and sustained by the advection of background moisture by anomalous quasi-biweekly ascending motions. These ascending motions were stimulated by a positive vertical gradient of potential vorticity advection, which resulted from interactions between the potential vorticity perturbations on an eastward-propagating quasi-biweekly wave train and the background subtropical westerlies. Evaluations of subseasonal-to-seasonal prediction models exhibit limited skill in predicting this extreme event at lead times beyond 10 days. The forecast deficiencies are primarily attributed to models’ inadequate representation of the mid-latitude quasi-biweekly variability and the involved dynamical conditions. Our findings highlight that accurate prediction of the Eurasian mid-latitude quasi-biweekly variability and associated scale interactions are critical for improving early warnings of persistent extreme rainfall in North China.
Assimilating satellite retrieved temperature and humidity profiles in cloudy regions remains attractive for numerical weather prediction (NWP). Current operational systems primarily rely on a limited number of radiance channels from hyperspectral sounders. However, compactly retrieved profiles from multiple instruments and all available channels, especially those generated efficiently using machine learning algorithms, present a promising alternative. These retrievals can be produced under both clear and cloudy conditions, making it crucial to understand how cloudiness affects the impact of assimilation. In this study, atmospheric temperature and humidity profiles jointly retrieved from the Cross-track Infrared Sounder (CrIS) and Advanced Technology Microwave Sounder (ATMS) onboard NOAA-20 satellite were assimilated into a regional NWP model using a three-dimensional variational (3D-Var) method. The impacts of different cloud amounts and cloud-top heights on tropical cyclone (TC) forecasts were examined for Typhoon Muifa. Assimilating NOAA Unique Combined Atmospheric Processing System (NUCAPS) profiles improved the thermodynamic structure of the initial field and enhanced typhoon forecasts. The all-sky profile assimilation reduced track forecast errors by up to 200 km after 48 hours, and increased the equitable threat score (ETS) for 72-hour accumulated precipitation by about 74
The South China Sea (SCS) is located at the triple junction of the Eurasian, Indo-Australia, and Philippine Sea plates, the underlying mantle nature and heterogeneity have not been well understood. This study presents results of copper isotopic compositions of seafloor basaltic rocks recovered at IODP Sites U1431, U1500, U1433, and U1434 in the SCS, aiming to elucidate the mechanisms responsible for the observed mantle heterogeneity. The MORB-type basalts at Site U1431 in the East Sub-basin have systematically lower δ65Cu (−0.05‰±0.02‰ to −0.01‰±0.03‰) than those of basalts at Sites U1500, U1433 and U1434 (δ65Cu=0.04‰±0.01‰–0.10‰±0.03‰), which fall within a typical terrestrial mantle (0.07‰±0.10‰). The large variations in copper isotopic compositions of the SCS basalts are attributed to partial melting and mantle source characteristics of mantle rocks, rather than to low-temperature alteration, sulfur-bearing fluids, or fractional crystallization. Low-temperature altered oceanic crust does not alter Cu isotopic compositions, whereas high-temperature alteration of lower oceanic crust produce a pronounced light Cu isotope signature. The geochemical signatures of Site U1431 basalts can be explained by the mixing of normal mantle with over 10
The Xinfengjiang Reservoir in China has experienced sustained elevated seismicity since the 1962 M6.1 earthquake, yet the corresponding fault zone structure and earthquake mechanisms remain poorly understood, particularly regarding the long-term mechanical evolution and the relationship to recent seismicity. Using continuous waveforms from the Xinfengjiang regional broadband network from 2013 to 2014, we compiled a high-precision earthquake catalog along with focal mechanism solutions for 471 events via machine-learning-based phase picking and polarity identification. Based on the seismicity distribution, we define four major seismic zones: Xichang located northwest of the reservoir, Kuzhong (the central area of the reservoir), Dam-Valley area, and Heyuan city. Applying spatial principal component analysis, we identified 30 active faults whose orientations are largely consistent with the focal mechanisms of small earthquakes. We then calculate the excess fluid pressure and find the following results. The seismicity in Kuzhong and Dam-Valley area is predominantly controlled by reservoir-induced fluid migration. The faults beneath Kuzhong are shallower with a direct fluid migration channel, making them most prone to triggering. The faults in the Dam-Valley area exhibit lower excess fluid pressures, and the seismicity delineates two fluid-infiltration channels with pressure concentration near the low-permeability bodies. Xichang became active only after >50 years of impoundment, and the seismicity indicates a typical process of “flow-blocking by low-permeability bodies, pressure accumulation, and rupture”. In contrast, seismicity in Heyuan city is mainly governed by the regional NW-SE compressional stress field, which has fostered a mature Riedel shear system with a principal deformation zone striking 265°. These results provide useful clues for understanding the earthquake mechanisms in the Xinfengjiang and other reservoir areas.
The persistent heavy precipitation associated with the Meiyu front usually features zonal rainbelts with meridional migrations across East Asia in boreal summer and triggers flooding disasters. Its subseasonal forecasting remains inherently challenging, and especially for the rainbelt migration has been paid little attention to before. This study examines the subseasonal forecasting of Meiyu rainbelt meridional migrations and bias correction approach based on the datasets of two subseasonal-to-seasonal (S2S) models, viz., ECMWF and UKMO S2S models. We show that the forecasting skill of pentad-running-mean rainbelts significantly outperforms that of daily rainbelts at lead time over 2–3 weeks through quantifying the latitudinal location of rainbelt (LLR) and its anomaly in the two S2S models and introducing the spatio-temporal correlation coefficient (STCC) as a new skill to represent evolution of LLRs. Results show that the LLR forecasts of ECMWF-S2S have higher skills than those of UKMO-S2S, with a longer lead time reaching the same failure probability and valuable lead time extending up to 30 days by STCC. To overcome systematic forecasting errors in the model climatology, we further propose two reconstruction-based bias-correction approaches for improving the rainbelt forecasts by replacing the climatology of the S2S models with the observed in different stages, which consistently yields higher forecasting skills of LLRs than the original forecasts across all lead times. These findings provide an effective solution for the subseasonal forecasting of the Meiyu rainbelt meridional migrations represented by LLR through the model evaluations and bias corrections.
Sulfide oxidation coupled with carbonate weathering releases CO2 that can partially offset the CO2 consumed by silicate weathering. Therefore, the impact of chemical weathering on atmospheric CO2 ultimately depends on the relative magnitudes of these two processes. However, how chemical weathering and its impact on atmospheric CO2 respond to environmental factors such as erosion and runoff remains poorly constrained. In this study, we used river water chemistry, stable isotopes, and a convex optimization-based inverse model to quantify the contributions of silicates, carbonates, evaporites, sulfides, and precipitation to riverine solutes in the Lancang River basin of the southeastern Tibetan Plateau. The results show that carbonate weathering is the primary source of solutes, and the sulfuric acid derived from sulfide oxidation preferentially reacts with carbonates. After isolating the effect of runoff, we find that silicate weathering is negatively correlated with erosion rate, while carbonate weathering and sulfide oxidation exhibit a weakly positive correlation with erosion rate. We speculate that the intrinsic reactivity of minerals, sediment weathering, and the input of non-geothermal groundwater cause silicates, carbonates, and sulfides to exhibit differential erosion sensitivities. The differences in erosion sensitivity among minerals lead to a net release of CO2 from chemical weathering in highly eroded mountainous regions over million-year timescales, prompting a reassessment of the roles of orogeny and enhanced erosion in regulating Earth’s climate.
Granites are recognized as crucial parent rocks for rare-metal mineralization. The South China granite province is not only a major base of rare-metal resources in China, but also a globally significant example of rare-metal metallogeny. It is both necessary and timely to conduct a more detailed characterization of the regional distribution patterns, petrogenetic types, and metallogenic features of these rare-metal granites. Such insights will help deepen our knowledge of rare-metal mineralization associated with South China granites and guide future regional exploration for rare-metal resources. Although rare-metal granites are widely recognized in South China, they are mostly concentrated in the Nanling Range (NR) and Jiangnan Orogenic Belt (JOB). Based on lithogeochemical signatures, these granites can be further divided into peraluminous and metaluminous types, which correspond, respectively, to the Li-Cs-Ta (LCT) series and Nb-Y-F (NYF) series. In fact, granites in the NR and those in the central JOB exhibit a peraluminous to strongly peraluminous affinity with pronounced enrichment in Li, Rb, Cs, Be, and Ta (>Nb), and form the LCT-series mineralization. In contrast, granites in the eastern JOB are typically metaluminous to weakly peraluminous, featuring Nb (>Ta), Li, Zr, and REE mineralization, and thus belong to the NYF series. Integration of zircon and columbite Hf isotope data indicates that the source rocks for the formation and mineralization of the LCT granites in South China are predominantly mature continental crustal materials. By contrast, the NYF granites distributed along the Jiangshan-Shaoxing fault zone show significant involvement of juvenile crustal materials. From a metallogenic perspective, mineralization in both LCT- and NYF-series granites in South China can form a continuous system that evolves progressively from the magmatic, through the magmatic-hydrothermal transitional stage, ultimately to the hydrothermal stages. However, hydrothermal mineralization is notably more extensive and intense in the LCT granites, leading to large-scale greisen-, skarn-, and quartz vein-type mineralization, as well as the distinctive ribbon-rock type Li, Be, Rb, and Sn mineralization found in the NR. The LCT- and NYF-series granites each possess their own rare-metal metallogenic advantages and distinct ore potentials. Metaluminous NYF-series granites exhibit good potential for niobium mineralization, whereas peraluminous LCT-series granites represent key exploration targets for breakthroughs in emerging strategic resources such as rubidium and cesium.
Tropospheric ozone is jointly affected by anthropogenic activity and climate variability. However, the influence of cosmic rays on ozone through chemical reactions triggered by atmospheric ionization is not fully understood. Using observations of sunspot number and cosmic rays, this study incorporates a cosmic-ray-driven negative-ion chemical mechanism into the regional climate-chemistry-ecology coupled model RegCM-Chem-YIBs and quantifies the effects of cosmic rays on upper-tropospheric ozone and water vapor during a high-cosmic-ray year (2009) and a low-cosmic-ray year (2000). Investigations show that: (1) cosmic-ray is negatively correlated with solar activity, and the electron concentration produced by ionization in the high-cosmic-ray year is 14
The Jovian magnetodisk deviates from the geographical equator and is distributed close to the magnetic equator. The location and motion of the magnetodisk are vital parameters for studying the magnetospheric dynamics and the coupling with the ionosphere. The primary motion of the magnetodisk is rotating with Jupiter as the tilted magnetic dipole axis rotates about the planetary spin axis. Additionally, small-scale flapping-like motions are observed in the magnetodisk, although the mechanism behind these motions remains unclear. In this study, we find that when magnetic reconnection occurs, the magnetodisk current sheet behaves as a kink-like wave when crossing the spacecraft. The spacecraft then crosses the current sheet repeatedly and records multiple reconnection signals during one rotation period. These observations suggest that the multiple magnetic reconnection sites break the magnetodisk field lines, causing the current sheet to become a rippling-like structure, which also rotates with the magnetosphere.
The continental shelf, as a transitional zone between land and ocean, is one of the most active regions for material and energy exchange within the Earth system and plays a crucial role in regulating global climate and the carbon cycle. However, the response of silicate weathering on continental shelves to paleoclimate changes on glacial-interglacial timescales, as well as its impact on the global carbon cycle, remains unclear. In particular, there is a notable lack of long-term geological records from mid-latitude continental shelf regions, which are sensitive to temperature and sea-level changes. In this study, we conducts high-resolution clay mineral analyses on sediments from Site CSDP-1 in the South Yellow Sea continental shelf, aiming to reconstruct the history of sediment provenance and weathering evolution since the middle Pleistocene and identifying their controlling factors. Comprehensive analyses indicate that over the past 600,000 yr, fine-grained sediments in the study area were primarily derived from the Yellow River. Weathering indicators, including clay mineral ratios and major element geochemistry, suggest that enhanced chemical weathering occurred predominantly during glacial periods. This is likely due to the exposure of unconsolidated shelf sediments during glacial sealevel lowstands, making them susceptible to subaerial re-weathering. Our estimates indicate that the intensified silicate weathering of exposed sediments on the Yellow and East China Sea continental shelf during glacial periods contributed approximately 0.3
The Early Triassic witnessed dramatic climatic and environmental perturbations following the Permian-Triassic mass extinction. However, terrestrial responses to orbitally forced climate change remain poorly constrained, largely due to the limited availability of high-resolution chronological frameworks. Here, we apply time series analysis of natural gamma-ray logs and the first principal component of X-ray fluorescence elemental data from a terrestrial succession at the Dayulin section in North China (Sunjiagou-Liujiagou-Heshanggou formations). This study establishes a floating astronomical time scale by tuning the paleoclimate proxy series to the 405 kyr long-eccentricity cycle. Integrated with cycle-calibrated magnetostratigraphy, it provides a robust chronological framework for stratigraphic interpretation and inter-section correlation. Applying the sedimentary noise model to the tuned paleoclimate proxy series, we identify intervals of enhanced sedimentary noise that align with major facies transitions, suggesting that climatic instability may have influenced changes in the depositional regime. This study further reveals a 1.2 Myr obliquity modulation cycle corresponding to the Mars-Earth s4−s3 secular resonance during the Early Triassic, expressed within the sedimentary noise series. The detection of this modulation in a low-latitude continental succession highlights the influence of long-term orbital forcing on terrestrial hydroclimate and depositional stability. Moreover, our results provide a new reference framework for Early Triassic terrestrial astrochronology and a geological constraint for refining future astronomical solutions and inter-basin correlations.
Deep-sea profile observations are the key to decrypting the vertical distribution of life activities and quantifying the efficiency of the “biological pump”, yet such data remain scarce. In this study, we first used a Maxi Multinet Plankton Sampler to collect biological samples from nine continuous depth layers across a 4000 m profile on both sides of the Eauripik Rise in the Caroline Basin. Using on-site fixation, Rose Bengal staining, morphological identification, and statistical analysis, we quantitatively characterized the full-depth gradient succession of siliceous radiolarians and their environmental controls. Our results show that the total radiolarian abundance peaked at 0–100 m and decreased with increasing depth on both stations. Heatmap analysis based on species presence-absence data revealed that temperature controlled the vertical distribution succession of radiolarians, with distinct thermal niche differentiation from the surface to deep waters. Four depth-stratified species assemblages indicative of water mass environments were identified based on critical temperature thresholds of 24, 8, and 1.8 °C: Didymocyrtis tetrathalamus and Tetrapyle group as warm mixed layer species (>24 °C, 0–200 m); Larcopyle buetschlii as thermocline species (8–24 °C, 100–500 m); Cladoscenium ancoratum, Larcopyle weddellium, Cycladophora cf. davisiana, and Saturnalis circularis as low-temperature species (1.8–8°C, 500–2400 m); and Thecosphaera melitomma, Axoprunum octatignum, and Druppatractus hastatus as cold-water species (<1.8 °C, 2400–4000 m). Cluster analysis indicated that the community structures differed between the two sides of the Eauripik Rise, largely due to an uneven distribution of Antarctic Circumpolar Deep Water caused by topographic barrier effects. Above the ridge, however, communities exhibited a three-layer vertical structure with strong connectivity within each layer, consistent with the connectivity of upper and intermediate currents in the East and West Caroline Basin. These findings provide observational data and scientific support for understanding the vertical adaptation strategies of marine organisms and biogeochemical cycling in tropical waters.
Previous geodynamic theories have mainly focused on plate margins, and little is known about how tectonic evolution affects intracontinental processes. The nature of the Caledonian Orogenic Belt in South China is still controversial, but its intracontinental orogenic characteristics are relatively obvious. It was previously believed that mineralization was weak during the Caledonian period in South China. With in-depth geological research and exploration, a large number of Caledonian ore deposits have been successively discovered in South China in recent years. Integrating previous research results, this paper clarifies and determines that the Caledonian ore deposits in south China could be divided into four types, namely Cu polymetallic deposits related to granites that originated partially from the Neoproterozoic juvenile lower crust, W-Sn polymetallic deposits related to granites derived from the remelting of the Paleoproterozoic metamorphic basement, orogenic Au deposits, and MVT Pb-Zn deposits; these four types of ore deposits have consistent metallogenic ages, concentrated in 440–395 Ma, which is consistent with the peak ages of the Caledonian granites and the regional metamorphism of the pre-Devonian strata in South China. They are a unified whole with close genetic connections, and constitute the South China Caledonian intracontinental metallogenic system controlled by far-field stress. It is worth noting that the NE-trending Jiangshao-Chenzhou-Linwu Fault divides the South China Caledonian Orogenic Belt into two parts, with most known Caledonian ore deposits distributed in the western part of this fault. The metallogenic differences between the eastern and western sides of the fault or the metallogenic potential of the eastern region still need in-depth research.
