Amid overlapping crises and uncertainties as the world enters an era of turbulence and transformation,the countries of the Global South are swiftly emerging from the periphery of world politics to the forefront of int...Amid overlapping crises and uncertainties as the world enters an era of turbulence and transformation,the countries of the Global South are swiftly emerging from the periphery of world politics to the forefront of international cooperation,playing an increasingly vital role in advancing humanity’s collective progress.展开更多
South African scholars highlight the importance of Xi Jinping:The Governance of China China is playing an increasingly active and important role in global politics and economy,especially in the development of the Glob...South African scholars highlight the importance of Xi Jinping:The Governance of China China is playing an increasingly active and important role in global politics and economy,especially in the development of the Global South.展开更多
Southerly moisture surges over the central South China Sea(SCS)are characterized by the strengthening of lowlevel southerlies that transport moisture northward from the Pacific or Indian Oceans to South China.These su...Southerly moisture surges over the central South China Sea(SCS)are characterized by the strengthening of lowlevel southerlies that transport moisture northward from the Pacific or Indian Oceans to South China.These surge events typically occur for days in the early-summer season(from April to June)and can lead to heavy rains in South China.This study categorizes surge events into three types of flow patterns and examines their multiscale variations and impacts on rainfall.The first type occurs mainly in April,with the southeasterlies enhanced by a deepening trough in South China and the western Pacific subtropical high established over the SCS.The second type of surge events mostly appears in June,featuring the prevailing southwesterlies of summer monsoon from the Indian Ocean during the active phases of intraseasonal oscillations.Most surge events exhibit semi-diurnal variations with morning and afternoon peaks of northward moisture fluxes.Specifically,the first type features a dominant afternoon peak,while the second type shows a dominant early-morning peak,which is induced by thermal contrast between the Indochina Peninsula and the SCS.In general,the surge events enhance moisture convergence and increase rainfall downstream in South China,but they show some regional differences.The second type strengthens moisture convergence and rainfall in coastal regions with a morning peak.In contrast,the first type enhances inland rainfall with a morning peak,while moisture divergence dominates coastal regions.The third type of surge events denotes transitional conditions between the first two types,in terms of atmospheric circulations,diurnal cycles,and rainfall patterns.These results highlight a diversity of regional moisture surges and related rainfall ranging from diurnal to sub-seasonal scales.展开更多
This study explores the impact of winter sea surface temperature(SST)anomalies in the Southern Indian Ocean on summer precipitation patterns in China,utilizing data from reanalysis sources and Coupled Model Intercompa...This study explores the impact of winter sea surface temperature(SST)anomalies in the Southern Indian Ocean on summer precipitation patterns in China,utilizing data from reanalysis sources and Coupled Model Intercomparison Project Phase 6(CMIP6)models.The results reveal that the Southern Indian Ocean Dipole(SIOD),characterized by contrasting SST anomalies in the northeast and southwest regions,acts as a predictor for Chinese summer precipitation patterns,namely floods in the south and drought in the north.In a positive SIOD event,the southwestern Indian Ocean exhibits warmer SSTs,while the northeastern region remains cooler.A negative SIOD event shows the opposite pattern.During the positive phase of the SIOD,the winter SST distribution strengthens the 850-hPa cross-equatorial airflow,generating a robust low-level westerly jet that enhances water vapor transport to the Bay of Bengal(BoB).These air-sea interactions maintain lower SSTs in the northeastern region,which significantly increase the land-sea temperature contrast in the Northern Hemisphere during spring and summer.This strengthened thermal gradient intensifies the southwest monsoon,establishing a strong convergence zone near the South China Sea and amplifying monsoon-driven precipitation in South China.Additionally,CMIP6 models,such as NorESM2-LM and NorCPM1,which accurately simulate the SIOD pattern,effectively capture the seasonal response of cross-equatorial airflow driven by SST anomalies of Southern Indian Ocean.The result highlights the essential role of cross-equatorial airflow generated by the SIOD in forecasting crossseasonal precipitation patterns.展开更多
Global South,representing the collective of emerging markets and developing countries,is becoming a pivotal force in reshaping the international order.It plays a vital role in driving global governance reforms with th...Global South,representing the collective of emerging markets and developing countries,is becoming a pivotal force in reshaping the international order.It plays a vital role in driving global governance reforms with the principle of fairness and equity.展开更多
The petrogenesis and genetic link to polymetallic mineralization of the granites in the Dayishan complex,southern Hunan province remain debated.Here,we present an integrated study on the petrology,zircon U-Pb ages and...The petrogenesis and genetic link to polymetallic mineralization of the granites in the Dayishan complex,southern Hunan province remain debated.Here,we present an integrated study on the petrology,zircon U-Pb ages and whole-rock geochemistry for this complex.Our findings indicate that the southern complex consists of(amphibole-bearing)biotite granites and muscovite granites emplaced at 153-151 Ma,and the central and northern complex consists of two-mica granites and tourmaline-bearing muscovite granites,respectively with the former emplaced at 164 Ma and the latter at 150 Ma.The(amphibole-bearing)biotite granites have SiO_(2) contents of 68.0-73.8 wt% and are enriched in alkalis and rare earth elements and depleted in Sr and Ba.They display Zr+Y+Ce+Nb>350 ppm and 10000×Ga/Al>2.6 along with high zircon saturation temperatures(821-883oC).The two-mica granites and(tourmaline-bearing)muscovite granites have high SiO_(2)(74.4-77.3 wt%)and low Ga/Al,Zr+Nb+Ce+Y,K/Rb,Zr/Hf,and Nb/Ta along with low zircon saturation temperatures(709-817℃).Geochemical characteristics suggest that the(amphibole-bearing)biotite granites are A-type granites generated through shallow dehydration melting of early Paleozoic granitoids,and that the two-mica granites and(tourmaline-bearing)muscovite granites are fractionated A-type granites produced through fractionation crystallization from the(amphibole-bearing)biotite granites accompanied by fluid fractionation.展开更多
Both fractional crystallization and fluid-melt-crystal interaction are involved in the formation of highly fractionated granites.This paper assessed those two processes using geochemistry of muscovite and tourmaline a...Both fractional crystallization and fluid-melt-crystal interaction are involved in the formation of highly fractionated granites.This paper assessed those two processes using geochemistry of muscovite and tourmaline and bulkrock chemistry of multi-phase Wangxianling granitoids,South China.Compositional variations suggest the coarse-grained muscovite granite is produced from fractional crystallization of the two-mica granite whereas the fine-grained muscovite granite represents a distinct magma pulse.Progressive fractionation of quartz,feldspar and biotite leads to elevated boron and aluminum content in melt which promoted muscovite and tourmaline to crystallize,which promotes two-mica granite evolving towards tourmaline-bearing muscovite granite.Fluid-melt-crystal interaction occurred at the magmatichydrothermal transitional stage and resulted in the textural and chemical zonings of tourmaline and muscovite in finegrained muscovite granite.The rims of both tourmaline and muscovite are characterized by the enrichment of fluid mobile elements such as Li,Mn,Cs and Zn and heavierδ^(11)B values of the tourmaline rims(-15.0‰to-13.6‰)compared to cores(-15.7‰to-14.3‰).Meanwhile,significant M-type REE tetrad effects(TE_(1,3)=1.07-1.18)and low K/Rb ratios(48-52)also correspond to fluid-melt-crystal interaction.This study shows zoned muscovite and tourmaline can be excellent tracers of fractional crystallization and late-stage fluid-melt-crystal interaction in highly evolved magmatic systems.展开更多
The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nev...The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nevertheless,no systematic investigations on the classification and origin of oils and hy-drocarbon migration processes have been made for the entire petroleum system in this depression,which has significantly hindered the hydrocarbon exploration in the region.A total of 32 mudstone and 58 oil samples from the Fushan Depression were analyzed to definite the detailed oil-source correlation within the sequence and sedimentary framework.The organic matter of third member of Paleogene Liushagang Formation(Els(3))source rocks,both deltaic and lacustrine mudstone,are algal-dominated with high abundance of C_(23)tricyclic terpane and C_(30)4-methylsteranes.The deltaic source rocks occur-ring in the first member(Els_(1))and second member(Els_(2))of the Paleogene Liushagang Formation are characterized by high abundance of C_(19+20)tricyclic terpane and oleanane,reflecting a more terrestrial plants contribution.While lacustrine source rocks of Els_(1)and Els_(2)display the reduced input of terrige-nous organic matter with relatively low abundance of C 19+20 tricyclic terpane and oleanane.Three types of oils were identified by their biomarker compositions in this study.Most of the oils discovered in the Huachang and Bailian Els_(1)reservoir belong to group A and were derived from lacustrine source rocks of Els_(1)and Els_(2).Group B oils are found within the Els_(1)and Els_(2)reservoirs,showing a close relation to the deltaic source rocks of Els_(1)and Els_(2),respectively.Group C oils,occurring in the Els3 reservoirs,have a good affinity with the Els3 source rocks.The spatial distribution and accumulation of different groups of oils are mainly controlled by the sedimentary facies and specific structural conditions.The Els_(2)reservoir in the Yong'an area belonging to Group B oil,are adjacent to the source kitchen and could be considered as the favorable exploration area in the future.展开更多
The Late Cretaceous Jiepailing granitoids,located at the central Nanling Range in South China,are closely associated with significant Sn-Li-Be-F polymetallic metallogeny.The Jiepailing granitoids mainly consist of gra...The Late Cretaceous Jiepailing granitoids,located at the central Nanling Range in South China,are closely associated with significant Sn-Li-Be-F polymetallic metallogeny.The Jiepailing granitoids mainly consist of granitic porphyry and zinnwaldite granite.The two granitoids have an A-type affinity,showing elevated Rb/Sr ratios and significant depletions in Ba,Sr and P.Integrated zircon and monazite U-Pb dating results suggest that granitic porphyry and zinnwaldite granite were emplaced at~89 Ma and~94 Ma,respectively.The low Ce^(4+)/Ce^(3+)ratios of the Jiepailing granitoids,together with significant negative Eu anomalies of the zircons,indicate that their formation occurred under conditions of reduced oxygen fugacity.Through the analysis of zircon Hf-O and whole-rock Nd isotopes,it has been determined that both stages of the Jiepailing granitoids originated in the lower-middle Mesoproterozoic crustal basement[ε_(Nd)(t)=−5.33 to−4.96,t^(C)_(DM)(Nd)=1289-1234 Ma,ε_(Hf)(t)=−4.13 to+2.22,t^(C)_(DM)(Hf)=1418-1015 Ma andδ^(18)O_(Zrc)=6.33‰-7.72‰],with the involvement of mantle-derived materials.Both granitic porphyry and zinnwaldite granite exhibit elevated concentrations of fluorine(F),with the positive correlation between F and Sn emphasizing the crucial role of high F sources in tin mineralization.Drawing upon the study of the Late Cretaceous magma systems in southern Hunan and through comparison with the mineralized granites observed in coastal regions during the Late Cretaceous,a genetic model for the mineralized granites in the Nanling region is developed.When the Paleo-Pacific Plate retreated to the coastal region,the continental crust in southern China underwent extensional thinning and asthenospheric upwelling due to gravitational collapse.Such processes resulted in the partial melting of the middle-lower crustal metamorphic sedimentary basement and the subsequent formation of F-rich granitic magmas,related to tin mineralization.展开更多
On 19 May 2022, an outbreak of 105 red sprites that occurred over South Asia was fortuitously recorded by two amateurs from a site in the southern Tibetan Plateau(TP), marking the highest number captured over a single...On 19 May 2022, an outbreak of 105 red sprites that occurred over South Asia was fortuitously recorded by two amateurs from a site in the southern Tibetan Plateau(TP), marking the highest number captured over a single thunderstorm in South Asia. Nearly half of these events involved dancing sprites, with an additional 16 uncommon secondary jets and at least four extremely rare green emissions called “ghosts” observed following the associated sprites. Due to the absence of the precise timing needed to identify parent lightning, a method based on satellite motion trajectories and star fields is proposed to infer video frame timestamps within an error of less than one second. After verifying 95 sprites from two videos, our method identified the parent lightning for 66 sprites(~70%). The sprite-producing strokes, mainly of positive polarity with peak currents exceeding +50 k A, occurred in the stratiform region of a mesoscale convective complex(MCC)that spanned the Ganges Plain to the southern TP, with a cloud area over 200 000 km2 and a minimum cloud-top black body temperature near 180 K. This observation confirms that thunderstorms in South Asia, akin to mesoscale convective systems(MCSs) in the Great Plains of the United States or coastal thunderstorms in Europe, can produce numerous sprites,including complex species. Our analysis bears important implications for characterizing thunderstorms above the southern TP and examining their physical and chemical effects on the adjacent regions, as well as the nature of the coupling between the troposphere and middle-upper atmosphere in this region.展开更多
Geological deformations are generally attributed to compressional, extensional and strike-slip processes. Since the breakup of Gondwana, torque deformation has been responsible for the current configuration of the wes...Geological deformations are generally attributed to compressional, extensional and strike-slip processes. Since the breakup of Gondwana, torque deformation has been responsible for the current configuration of the western coasts of Africa and the eastern shore of South America and the morphotectonic geometry of the rift basins of South America, conditioning the morphostructure of the Andean chain and the current geoforms of the foreland.展开更多
Objective: We aim to analyze the surgical nursery of abdominal wall hernias in adults between two poorly fitted medical environments, the Regional Hospital Center of Tsévié (RHC-T) and the Prefectural Hospit...Objective: We aim to analyze the surgical nursery of abdominal wall hernias in adults between two poorly fitted medical environments, the Regional Hospital Center of Tsévié (RHC-T) and the Prefectural Hospital Center of Kpalimé (PHC-K) in Togo. Methodology: It was a retrospective, descriptive and comparative study carried out over five years (2018-2022) focusing on abdominal wall hernias in adults. Information was gathered from the patients’clinical notes and registers on the frequency of hernias, the anatomo-clinical forms of hernias, the type of anesthesia, the hernia repair technique and the postoperative evolution. Results: Of the 1022 and 1026 operations performed, 312 and 412 were hernial repairs, representing 30.5% and 41.2% of operations at RHC-T and PHC-K respectively (p = 0.001). The inguinal hernia was the most often found in 83.7% (n = 261) at RHC-T versus 76.6% (n = 324) at PHC-K. Herniorrhaphy was the most frequently used repair method, in 93.6% (n = 292) of patients at RHC-T and in 91.3% (n = 376) at PHC-K (p = 0.11). Postoperative complications were noted in 5.1% of cases (n = 16) at RHC-T versus 3.5% of cases (n = 15) at PHC-K (p = 0.307). These complications included scrotal hematomas, surgical areas infections, and orchitis. We recorded 1.3% (n = 4) and 0.8% (n = 3) deaths at RHC-T and PHC-K respectively (p = 0.496). Conclusion: There is homogeneity in the treatment of hernia in these two hospitals in Togo.展开更多
The relation between conflict and governance has been dominated by type of government rather than by system of government.With increasing conflict in countries with ethnic and religious diversity,the debate has gradua...The relation between conflict and governance has been dominated by type of government rather than by system of government.With increasing conflict in countries with ethnic and religious diversity,the debate has gradually shifted to understand better the link between conflict and system of government.There is a growing evidence that suggests federal system performs better than unitary system in managing diversity and reducing conflict.Decentralization is even seen to be more effective than federal system not only in managing diversity and reducing conflict but also in delivering public goods.This article provides an account of evolution of system of government in South Sudan.It finds a clear association of centralized unitary system with violent conflict and a relative peace during period of decentralized government or federal system.A decentralized federal system may be appropriate for South Sudan in managing diversity and mitigating conflict.Despite the popular demand by their citizens for a federal system to manage diversity and reduce violent conflict,the ruling elites in the post-independent South Sudan adopted instead an autocratic centralized unitary system that contributed among other factors to the persistent violent conflicts,erosion of social cohesion,and rising mistrust between state and citizens and between and among the communities of South Sudan.展开更多
This paper examines World Geopark in South Korea as a case study.It begins by outlining the geological and tectonic background of the Korean Peninsula,whose basement consists of Archean to Paleoproterozoic rocks.These...This paper examines World Geopark in South Korea as a case study.It begins by outlining the geological and tectonic background of the Korean Peninsula,whose basement consists of Archean to Paleoproterozoic rocks.These rocks form three continental blocks and constitute a rich geological foundation shaped by multi-stage evolution.The distribution and characteristics of global geoparks are then analyzed.As of 2025,South Korea is home to seven UNESCO Global Geoparks(designated between 2010 and 2025),which feature diverse landforms such as volcanic,sedimentary,and structural formations,with some sites also encompassing cultural relics.Finally,the study highlights that 25 of South Korea's national parks have not yet applied for geopark status and thus hold significant potential.Due to differing evaluation criteria between UNESCO Global Geoparks and South Korea's national parks,future applications involving multiple parks could expand the scale of geoparks,providing valuable insights for geoscience research and park development across East Asia.展开更多
The world is now undergoing profound changes unseen in a century,with unilateralism and protectionism gaining momentum.As the head of the Asia-Pacific Think Tank,I would like to discuss the mission and responsibilitie...The world is now undergoing profound changes unseen in a century,with unilateralism and protectionism gaining momentum.As the head of the Asia-Pacific Think Tank,I would like to discuss the mission and responsibilities of China and ASEAN under the tariff hegemony of the United States.展开更多
There is a growing recognition of the critical role of security governance in advancing democratic transition in the post-conflict environment.Despite such a recognition,the security sector reform concept has overshad...There is a growing recognition of the critical role of security governance in advancing democratic transition in the post-conflict environment.Despite such a recognition,the security sector reform concept has overshadowed the importance of the overarching strategic role of security governance in transition to democracy,particularly in Africa.This paper assesses the status and challenges facing security governance and how they thwarted the efforts to furthering the democratic transition in South Sudan.The paper shows a deterioration in security,safety and security governance outcomes since the independence of South Sudan in 2011 with such a trend unlikely to be abated in the near future without strategic interventions.Some of the challenges facing security governance in South Sudan include the legacies of some historical events including the“Big Tent Policy”,absence of strategic leadership,lack of overarching policy framework,impractical and tenuous security arrangements in the 2018 peace agreement,persistent postponement of the first elections,and dysfunctional justice sector.The paper provides some strategic and operational recommendations to improve security governance and advance democratic transition in South Sudan.These recommendations include formulation of an inclusive and people-centered national security policy,rigorous judicial reform,and early political agreement on new political infrastructure if conditions for holding the first national elections are not met in 2026.展开更多
Granite origin is crucial to understanding the evolution of continental crust,yet many concerns about granite genesis remain yielding ongoing debates.A new integrated study of petrology,geochronology,mineral chemistry...Granite origin is crucial to understanding the evolution of continental crust,yet many concerns about granite genesis remain yielding ongoing debates.A new integrated study of petrology,geochronology,mineral chemistry and whole-rock geochemistry of the Dupangling granitic complex in South China,indicate that the granites in the western complex were emplaced during the Caledonian(418 Ma);they have SiO_(2)contents of 68.1-70.4 wt%,and are calc-alkaline and strongly peraluminous with high maficity[(TFe_(2)O_(3)+MgO)>4.0 wt%]and exhibit^(87)Sr/^(86)Sr(t)of 0.7234-0.7311 andε_(Nd)(t)of-9.0 to-6.7.The granites in the eastern complex,emplaced during the Indosinian(212 Ma),have high SiO_(2)contents(73.3-79.8 wt%)and exhibit affinities with A-type granites,such as enrichment in alkalis and rare earth elements(REEs),and depletion in Sr and Ba along with high TFeO/(TFeO+MgO),Ga/Al and Zr+Y+Ce+Nb;these granites exhibit^(87)Sr/^(86)Sr(t)of 0.7221 andε_(Nd)(t)of-9.2 to-7.5.Geochemical characteristics suggest that the older Caledonian granites were derived through dehydration melting of Paleoproterozoic metasedimentary rocks plus additional(~20%-32%)input from mafic magma,whereas the Indosinian granites were generated through shallow dehydration melting of the Caledonian granitoids.展开更多
The origins of peloidal micrites in reefal limestone are not yet well understood.Moscovian microbial reefs with abundant peloidal micrites from Guizhou,South China,provide an opportunity to study the peloids and their...The origins of peloidal micrites in reefal limestone are not yet well understood.Moscovian microbial reefs with abundant peloidal micrites from Guizhou,South China,provide an opportunity to study the peloids and their geological significance for this time interval.Three types of peloids are differentiated:microbial,lithic,and bioclastic peloids.Microbial peloids that are well-sorted and may form in situ by microbial activities.The poorly sorted lithic peloids are derived from erosion and redeposition of the micrite matrix caused by the bottom turbulence induced by periodic storms.Bioclastic peloids are completely micritized fragments of hard parts and shells.Microbial boring and encrustations promote the processes of micritization.Microbial peloids commonly develop in zones with low or normal energy levels,and contribute to the construction and stabilization of the framework.In contrast,the occurrence of lithic peloids reflects that the reefs are destroyed by bottom turbulence during growth.It is suggested that the microbial reefs were deposited under a dynamic balance between constructional versus destructive processes.By comparative analysis,the peloids as microbial in origin play a key role in the growth and stabilization of bioconstructions during Carboniferous,which should be paid more attention in the studies of Carboniferous buildups.展开更多
Apatite(U-Th)/He and fission track dating and tectono-thermal history modeling were used to reconstruct the Meso-Cenozoic tectonic evolution of the Huangling paleo-uplift in the Middle Yangtze Block,South China.The te...Apatite(U-Th)/He and fission track dating and tectono-thermal history modeling were used to reconstruct the Meso-Cenozoic tectonic evolution of the Huangling paleo-uplift in the Middle Yangtze Block,South China.The tectono-thermal evolution showed different tectonic exhumation/subsidence processes in the tectonic evolution of the foreland basin.The apatite(U-Th)/He ages ranged from 31.3 to 77.8 Ma,recording the thermal events of the Cenozoic Himalayan movement and indicating progressive exhumation extending from the southeast to the northwest.The thermal information of the Mesozoic Yanshan movement period was recorded by the apatite fission track age with a pooled age of 93.8 to 147 Ma.The exhumation of the Huangling paleo-uplift began in the Late Jurassic.The tectono-thermal evolution was characterized by a rapid uplift during 140-115 Ma,subsidence during 115-60 Ma,a rapid uplift during 40-30 Ma,and a slow uplift from 30 Ma to the present.The western Hunan-Hubei Depression was exhumed in the Middle Jurassic,and the tectono-thermal evolution was characterized by a rapid uplift during 160-135 Ma,a slow uplift during 135-50 Ma,a rapid uplift during 50-25 Ma,and a slow uplift from 25 Ma to the present.This Cenozoic exhumation was a response to the far field effect of the eastward growth of the Tibetan Plateau.The Cretaceous basins exposed in the surrounding areas of the Huangling paleo-uplift(Zigui basin,Yichang slope,and Huaguoping synclinorium)are foreland basins formed by the bi-directional compression of the Qinling-Dabie orogenic belt and the Xuefengshan intracontinental deformation system.展开更多
The pervasively distributed granitoids in South China contributed greatly to regional polymetallic mineralization,including tungsten,tin,copper,gold,rare metals,and rare earth elements(REEs).To ascertain the dynamic b...The pervasively distributed granitoids in South China contributed greatly to regional polymetallic mineralization,including tungsten,tin,copper,gold,rare metals,and rare earth elements(REEs).To ascertain the dynamic backgrounds,rock types and genesis of the parent rocks related to the Early-Middle Jurassic ionic rare earth mineralization,typical deposits at Muzishan,Xiahu,and Zudong were investigated by conducting petrographic,geochronologic,whole-rock geochemical,and Sr-Nd-Pb isotope analyses,which found that the parent rocks from the Muzishan deposit were the A1-type K-feldspar granite(~195 Ma),from the Zudong deposit were the A2-type monzogranite(~171 Ma),and from the Xiahu deposit were the I-type monzogranite(~167 Ma).All the three granitic rocks underwent different degrees of fractionation,with the Xiahu granite experiencing the highest degree,followed by the Zudong granite,and the Muzishan granite undergoing the lowest degree.The Muzishan granite was concluded to be formed under an intraplate extensional tectonic regime influenced by the hotspots or the mantle plume.The Zudong granite was formed in a post-arc extensional setting related to subduction-collision-rollback of the paleo-Pacific Plate,which caused upwelling of the asthenosphere,thinning of the lithosphere,and partial melting of crustal materials.The Xiahu granite was generated under a transitional tectonic setting of extension and compression,triggered by delamination and rollback of the paleo-Pacific Plate.展开更多
文摘Amid overlapping crises and uncertainties as the world enters an era of turbulence and transformation,the countries of the Global South are swiftly emerging from the periphery of world politics to the forefront of international cooperation,playing an increasingly vital role in advancing humanity’s collective progress.
文摘South African scholars highlight the importance of Xi Jinping:The Governance of China China is playing an increasingly active and important role in global politics and economy,especially in the development of the Global South.
基金Guangdong Major Project of Basic and Applied Basic Research(2020B0301030004)National Natural Science Foundation of China(42475003)Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(SML2023SP209)。
文摘Southerly moisture surges over the central South China Sea(SCS)are characterized by the strengthening of lowlevel southerlies that transport moisture northward from the Pacific or Indian Oceans to South China.These surge events typically occur for days in the early-summer season(from April to June)and can lead to heavy rains in South China.This study categorizes surge events into three types of flow patterns and examines their multiscale variations and impacts on rainfall.The first type occurs mainly in April,with the southeasterlies enhanced by a deepening trough in South China and the western Pacific subtropical high established over the SCS.The second type of surge events mostly appears in June,featuring the prevailing southwesterlies of summer monsoon from the Indian Ocean during the active phases of intraseasonal oscillations.Most surge events exhibit semi-diurnal variations with morning and afternoon peaks of northward moisture fluxes.Specifically,the first type features a dominant afternoon peak,while the second type shows a dominant early-morning peak,which is induced by thermal contrast between the Indochina Peninsula and the SCS.In general,the surge events enhance moisture convergence and increase rainfall downstream in South China,but they show some regional differences.The second type strengthens moisture convergence and rainfall in coastal regions with a morning peak.In contrast,the first type enhances inland rainfall with a morning peak,while moisture divergence dominates coastal regions.The third type of surge events denotes transitional conditions between the first two types,in terms of atmospheric circulations,diurnal cycles,and rainfall patterns.These results highlight a diversity of regional moisture surges and related rainfall ranging from diurnal to sub-seasonal scales.
基金Guangdong Major Project of Basic and Applied Basic Research(2020B0301030004)National Natural Science Foundation of China(U2442202)+1 种基金Key Innovation Team of China Meteorological Administration“Climate Change Detection and Response”(CMA2022ZD03)National Key Research and Development Program of China(2023YFF0805104)。
文摘This study explores the impact of winter sea surface temperature(SST)anomalies in the Southern Indian Ocean on summer precipitation patterns in China,utilizing data from reanalysis sources and Coupled Model Intercomparison Project Phase 6(CMIP6)models.The results reveal that the Southern Indian Ocean Dipole(SIOD),characterized by contrasting SST anomalies in the northeast and southwest regions,acts as a predictor for Chinese summer precipitation patterns,namely floods in the south and drought in the north.In a positive SIOD event,the southwestern Indian Ocean exhibits warmer SSTs,while the northeastern region remains cooler.A negative SIOD event shows the opposite pattern.During the positive phase of the SIOD,the winter SST distribution strengthens the 850-hPa cross-equatorial airflow,generating a robust low-level westerly jet that enhances water vapor transport to the Bay of Bengal(BoB).These air-sea interactions maintain lower SSTs in the northeastern region,which significantly increase the land-sea temperature contrast in the Northern Hemisphere during spring and summer.This strengthened thermal gradient intensifies the southwest monsoon,establishing a strong convergence zone near the South China Sea and amplifying monsoon-driven precipitation in South China.Additionally,CMIP6 models,such as NorESM2-LM and NorCPM1,which accurately simulate the SIOD pattern,effectively capture the seasonal response of cross-equatorial airflow driven by SST anomalies of Southern Indian Ocean.The result highlights the essential role of cross-equatorial airflow generated by the SIOD in forecasting crossseasonal precipitation patterns.
文摘Global South,representing the collective of emerging markets and developing countries,is becoming a pivotal force in reshaping the international order.It plays a vital role in driving global governance reforms with the principle of fairness and equity.
基金supported financially by the National Natural Science Foundation of China(Grant Nos.41872054 and 41272083)。
文摘The petrogenesis and genetic link to polymetallic mineralization of the granites in the Dayishan complex,southern Hunan province remain debated.Here,we present an integrated study on the petrology,zircon U-Pb ages and whole-rock geochemistry for this complex.Our findings indicate that the southern complex consists of(amphibole-bearing)biotite granites and muscovite granites emplaced at 153-151 Ma,and the central and northern complex consists of two-mica granites and tourmaline-bearing muscovite granites,respectively with the former emplaced at 164 Ma and the latter at 150 Ma.The(amphibole-bearing)biotite granites have SiO_(2) contents of 68.0-73.8 wt% and are enriched in alkalis and rare earth elements and depleted in Sr and Ba.They display Zr+Y+Ce+Nb>350 ppm and 10000×Ga/Al>2.6 along with high zircon saturation temperatures(821-883oC).The two-mica granites and(tourmaline-bearing)muscovite granites have high SiO_(2)(74.4-77.3 wt%)and low Ga/Al,Zr+Nb+Ce+Y,K/Rb,Zr/Hf,and Nb/Ta along with low zircon saturation temperatures(709-817℃).Geochemical characteristics suggest that the(amphibole-bearing)biotite granites are A-type granites generated through shallow dehydration melting of early Paleozoic granitoids,and that the two-mica granites and(tourmaline-bearing)muscovite granites are fractionated A-type granites produced through fractionation crystallization from the(amphibole-bearing)biotite granites accompanied by fluid fractionation.
基金funded by the National Natural Science Foundation of China(Grant Nos.42072089 and 41530206)。
文摘Both fractional crystallization and fluid-melt-crystal interaction are involved in the formation of highly fractionated granites.This paper assessed those two processes using geochemistry of muscovite and tourmaline and bulkrock chemistry of multi-phase Wangxianling granitoids,South China.Compositional variations suggest the coarse-grained muscovite granite is produced from fractional crystallization of the two-mica granite whereas the fine-grained muscovite granite represents a distinct magma pulse.Progressive fractionation of quartz,feldspar and biotite leads to elevated boron and aluminum content in melt which promoted muscovite and tourmaline to crystallize,which promotes two-mica granite evolving towards tourmaline-bearing muscovite granite.Fluid-melt-crystal interaction occurred at the magmatichydrothermal transitional stage and resulted in the textural and chemical zonings of tourmaline and muscovite in finegrained muscovite granite.The rims of both tourmaline and muscovite are characterized by the enrichment of fluid mobile elements such as Li,Mn,Cs and Zn and heavierδ^(11)B values of the tourmaline rims(-15.0‰to-13.6‰)compared to cores(-15.7‰to-14.3‰).Meanwhile,significant M-type REE tetrad effects(TE_(1,3)=1.07-1.18)and low K/Rb ratios(48-52)also correspond to fluid-melt-crystal interaction.This study shows zoned muscovite and tourmaline can be excellent tracers of fractional crystallization and late-stage fluid-melt-crystal interaction in highly evolved magmatic systems.
基金funded by the South Oil Exploration and Development Company of PetroChina(2021-HNYJ-010).
文摘The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nevertheless,no systematic investigations on the classification and origin of oils and hy-drocarbon migration processes have been made for the entire petroleum system in this depression,which has significantly hindered the hydrocarbon exploration in the region.A total of 32 mudstone and 58 oil samples from the Fushan Depression were analyzed to definite the detailed oil-source correlation within the sequence and sedimentary framework.The organic matter of third member of Paleogene Liushagang Formation(Els(3))source rocks,both deltaic and lacustrine mudstone,are algal-dominated with high abundance of C_(23)tricyclic terpane and C_(30)4-methylsteranes.The deltaic source rocks occur-ring in the first member(Els_(1))and second member(Els_(2))of the Paleogene Liushagang Formation are characterized by high abundance of C_(19+20)tricyclic terpane and oleanane,reflecting a more terrestrial plants contribution.While lacustrine source rocks of Els_(1)and Els_(2)display the reduced input of terrige-nous organic matter with relatively low abundance of C 19+20 tricyclic terpane and oleanane.Three types of oils were identified by their biomarker compositions in this study.Most of the oils discovered in the Huachang and Bailian Els_(1)reservoir belong to group A and were derived from lacustrine source rocks of Els_(1)and Els_(2).Group B oils are found within the Els_(1)and Els_(2)reservoirs,showing a close relation to the deltaic source rocks of Els_(1)and Els_(2),respectively.Group C oils,occurring in the Els3 reservoirs,have a good affinity with the Els3 source rocks.The spatial distribution and accumulation of different groups of oils are mainly controlled by the sedimentary facies and specific structural conditions.The Els_(2)reservoir in the Yong'an area belonging to Group B oil,are adjacent to the source kitchen and could be considered as the favorable exploration area in the future.
基金financially supported by the National Natural Science Foundation of China(Grant No.42303073).
文摘The Late Cretaceous Jiepailing granitoids,located at the central Nanling Range in South China,are closely associated with significant Sn-Li-Be-F polymetallic metallogeny.The Jiepailing granitoids mainly consist of granitic porphyry and zinnwaldite granite.The two granitoids have an A-type affinity,showing elevated Rb/Sr ratios and significant depletions in Ba,Sr and P.Integrated zircon and monazite U-Pb dating results suggest that granitic porphyry and zinnwaldite granite were emplaced at~89 Ma and~94 Ma,respectively.The low Ce^(4+)/Ce^(3+)ratios of the Jiepailing granitoids,together with significant negative Eu anomalies of the zircons,indicate that their formation occurred under conditions of reduced oxygen fugacity.Through the analysis of zircon Hf-O and whole-rock Nd isotopes,it has been determined that both stages of the Jiepailing granitoids originated in the lower-middle Mesoproterozoic crustal basement[ε_(Nd)(t)=−5.33 to−4.96,t^(C)_(DM)(Nd)=1289-1234 Ma,ε_(Hf)(t)=−4.13 to+2.22,t^(C)_(DM)(Hf)=1418-1015 Ma andδ^(18)O_(Zrc)=6.33‰-7.72‰],with the involvement of mantle-derived materials.Both granitic porphyry and zinnwaldite granite exhibit elevated concentrations of fluorine(F),with the positive correlation between F and Sn emphasizing the crucial role of high F sources in tin mineralization.Drawing upon the study of the Late Cretaceous magma systems in southern Hunan and through comparison with the mineralized granites observed in coastal regions during the Late Cretaceous,a genetic model for the mineralized granites in the Nanling region is developed.When the Paleo-Pacific Plate retreated to the coastal region,the continental crust in southern China underwent extensional thinning and asthenospheric upwelling due to gravitational collapse.Such processes resulted in the partial melting of the middle-lower crustal metamorphic sedimentary basement and the subsequent formation of F-rich granitic magmas,related to tin mineralization.
基金supported by the National Natural Science Foundation of China (Grant No.42394122)CAS Project of Stable Support for Youth Team in Basic Research Field (YSRR-018)+1 种基金the National Key R&D Program of China (2023YFC3007703)the Chinese Meridian Project, and the International Partnership Program of Chinese Academy of Sciences (183311KYSB20200003)。
文摘On 19 May 2022, an outbreak of 105 red sprites that occurred over South Asia was fortuitously recorded by two amateurs from a site in the southern Tibetan Plateau(TP), marking the highest number captured over a single thunderstorm in South Asia. Nearly half of these events involved dancing sprites, with an additional 16 uncommon secondary jets and at least four extremely rare green emissions called “ghosts” observed following the associated sprites. Due to the absence of the precise timing needed to identify parent lightning, a method based on satellite motion trajectories and star fields is proposed to infer video frame timestamps within an error of less than one second. After verifying 95 sprites from two videos, our method identified the parent lightning for 66 sprites(~70%). The sprite-producing strokes, mainly of positive polarity with peak currents exceeding +50 k A, occurred in the stratiform region of a mesoscale convective complex(MCC)that spanned the Ganges Plain to the southern TP, with a cloud area over 200 000 km2 and a minimum cloud-top black body temperature near 180 K. This observation confirms that thunderstorms in South Asia, akin to mesoscale convective systems(MCSs) in the Great Plains of the United States or coastal thunderstorms in Europe, can produce numerous sprites,including complex species. Our analysis bears important implications for characterizing thunderstorms above the southern TP and examining their physical and chemical effects on the adjacent regions, as well as the nature of the coupling between the troposphere and middle-upper atmosphere in this region.
文摘Geological deformations are generally attributed to compressional, extensional and strike-slip processes. Since the breakup of Gondwana, torque deformation has been responsible for the current configuration of the western coasts of Africa and the eastern shore of South America and the morphotectonic geometry of the rift basins of South America, conditioning the morphostructure of the Andean chain and the current geoforms of the foreland.
文摘Objective: We aim to analyze the surgical nursery of abdominal wall hernias in adults between two poorly fitted medical environments, the Regional Hospital Center of Tsévié (RHC-T) and the Prefectural Hospital Center of Kpalimé (PHC-K) in Togo. Methodology: It was a retrospective, descriptive and comparative study carried out over five years (2018-2022) focusing on abdominal wall hernias in adults. Information was gathered from the patients’clinical notes and registers on the frequency of hernias, the anatomo-clinical forms of hernias, the type of anesthesia, the hernia repair technique and the postoperative evolution. Results: Of the 1022 and 1026 operations performed, 312 and 412 were hernial repairs, representing 30.5% and 41.2% of operations at RHC-T and PHC-K respectively (p = 0.001). The inguinal hernia was the most often found in 83.7% (n = 261) at RHC-T versus 76.6% (n = 324) at PHC-K. Herniorrhaphy was the most frequently used repair method, in 93.6% (n = 292) of patients at RHC-T and in 91.3% (n = 376) at PHC-K (p = 0.11). Postoperative complications were noted in 5.1% of cases (n = 16) at RHC-T versus 3.5% of cases (n = 15) at PHC-K (p = 0.307). These complications included scrotal hematomas, surgical areas infections, and orchitis. We recorded 1.3% (n = 4) and 0.8% (n = 3) deaths at RHC-T and PHC-K respectively (p = 0.496). Conclusion: There is homogeneity in the treatment of hernia in these two hospitals in Togo.
文摘The relation between conflict and governance has been dominated by type of government rather than by system of government.With increasing conflict in countries with ethnic and religious diversity,the debate has gradually shifted to understand better the link between conflict and system of government.There is a growing evidence that suggests federal system performs better than unitary system in managing diversity and reducing conflict.Decentralization is even seen to be more effective than federal system not only in managing diversity and reducing conflict but also in delivering public goods.This article provides an account of evolution of system of government in South Sudan.It finds a clear association of centralized unitary system with violent conflict and a relative peace during period of decentralized government or federal system.A decentralized federal system may be appropriate for South Sudan in managing diversity and mitigating conflict.Despite the popular demand by their citizens for a federal system to manage diversity and reduce violent conflict,the ruling elites in the post-independent South Sudan adopted instead an autocratic centralized unitary system that contributed among other factors to the persistent violent conflicts,erosion of social cohesion,and rising mistrust between state and citizens and between and among the communities of South Sudan.
文摘This paper examines World Geopark in South Korea as a case study.It begins by outlining the geological and tectonic background of the Korean Peninsula,whose basement consists of Archean to Paleoproterozoic rocks.These rocks form three continental blocks and constitute a rich geological foundation shaped by multi-stage evolution.The distribution and characteristics of global geoparks are then analyzed.As of 2025,South Korea is home to seven UNESCO Global Geoparks(designated between 2010 and 2025),which feature diverse landforms such as volcanic,sedimentary,and structural formations,with some sites also encompassing cultural relics.Finally,the study highlights that 25 of South Korea's national parks have not yet applied for geopark status and thus hold significant potential.Due to differing evaluation criteria between UNESCO Global Geoparks and South Korea's national parks,future applications involving multiple parks could expand the scale of geoparks,providing valuable insights for geoscience research and park development across East Asia.
文摘The world is now undergoing profound changes unseen in a century,with unilateralism and protectionism gaining momentum.As the head of the Asia-Pacific Think Tank,I would like to discuss the mission and responsibilities of China and ASEAN under the tariff hegemony of the United States.
文摘There is a growing recognition of the critical role of security governance in advancing democratic transition in the post-conflict environment.Despite such a recognition,the security sector reform concept has overshadowed the importance of the overarching strategic role of security governance in transition to democracy,particularly in Africa.This paper assesses the status and challenges facing security governance and how they thwarted the efforts to furthering the democratic transition in South Sudan.The paper shows a deterioration in security,safety and security governance outcomes since the independence of South Sudan in 2011 with such a trend unlikely to be abated in the near future without strategic interventions.Some of the challenges facing security governance in South Sudan include the legacies of some historical events including the“Big Tent Policy”,absence of strategic leadership,lack of overarching policy framework,impractical and tenuous security arrangements in the 2018 peace agreement,persistent postponement of the first elections,and dysfunctional justice sector.The paper provides some strategic and operational recommendations to improve security governance and advance democratic transition in South Sudan.These recommendations include formulation of an inclusive and people-centered national security policy,rigorous judicial reform,and early political agreement on new political infrastructure if conditions for holding the first national elections are not met in 2026.
基金supported financially by the National Natural Science Foundation of China(Grant Nos.41872054 and 41272083)。
文摘Granite origin is crucial to understanding the evolution of continental crust,yet many concerns about granite genesis remain yielding ongoing debates.A new integrated study of petrology,geochronology,mineral chemistry and whole-rock geochemistry of the Dupangling granitic complex in South China,indicate that the granites in the western complex were emplaced during the Caledonian(418 Ma);they have SiO_(2)contents of 68.1-70.4 wt%,and are calc-alkaline and strongly peraluminous with high maficity[(TFe_(2)O_(3)+MgO)>4.0 wt%]and exhibit^(87)Sr/^(86)Sr(t)of 0.7234-0.7311 andε_(Nd)(t)of-9.0 to-6.7.The granites in the eastern complex,emplaced during the Indosinian(212 Ma),have high SiO_(2)contents(73.3-79.8 wt%)and exhibit affinities with A-type granites,such as enrichment in alkalis and rare earth elements(REEs),and depletion in Sr and Ba along with high TFeO/(TFeO+MgO),Ga/Al and Zr+Y+Ce+Nb;these granites exhibit^(87)Sr/^(86)Sr(t)of 0.7221 andε_(Nd)(t)of-9.2 to-7.5.Geochemical characteristics suggest that the older Caledonian granites were derived through dehydration melting of Paleoproterozoic metasedimentary rocks plus additional(~20%-32%)input from mafic magma,whereas the Indosinian granites were generated through shallow dehydration melting of the Caledonian granitoids.
基金supported by the National Natural Science Foundation of China(Grant Nos.42272008 and 41972002).
文摘The origins of peloidal micrites in reefal limestone are not yet well understood.Moscovian microbial reefs with abundant peloidal micrites from Guizhou,South China,provide an opportunity to study the peloids and their geological significance for this time interval.Three types of peloids are differentiated:microbial,lithic,and bioclastic peloids.Microbial peloids that are well-sorted and may form in situ by microbial activities.The poorly sorted lithic peloids are derived from erosion and redeposition of the micrite matrix caused by the bottom turbulence induced by periodic storms.Bioclastic peloids are completely micritized fragments of hard parts and shells.Microbial boring and encrustations promote the processes of micritization.Microbial peloids commonly develop in zones with low or normal energy levels,and contribute to the construction and stabilization of the framework.In contrast,the occurrence of lithic peloids reflects that the reefs are destroyed by bottom turbulence during growth.It is suggested that the microbial reefs were deposited under a dynamic balance between constructional versus destructive processes.By comparative analysis,the peloids as microbial in origin play a key role in the growth and stabilization of bioconstructions during Carboniferous,which should be paid more attention in the studies of Carboniferous buildups.
基金funded by the National Natural Science Foundation of China(U2244208,42302138)China Postdoctoral Science Foundation(No.2020M733869)Science Foundation of China University of Petroleum,Beijing(No.2462023XKBH003).
文摘Apatite(U-Th)/He and fission track dating and tectono-thermal history modeling were used to reconstruct the Meso-Cenozoic tectonic evolution of the Huangling paleo-uplift in the Middle Yangtze Block,South China.The tectono-thermal evolution showed different tectonic exhumation/subsidence processes in the tectonic evolution of the foreland basin.The apatite(U-Th)/He ages ranged from 31.3 to 77.8 Ma,recording the thermal events of the Cenozoic Himalayan movement and indicating progressive exhumation extending from the southeast to the northwest.The thermal information of the Mesozoic Yanshan movement period was recorded by the apatite fission track age with a pooled age of 93.8 to 147 Ma.The exhumation of the Huangling paleo-uplift began in the Late Jurassic.The tectono-thermal evolution was characterized by a rapid uplift during 140-115 Ma,subsidence during 115-60 Ma,a rapid uplift during 40-30 Ma,and a slow uplift from 30 Ma to the present.The western Hunan-Hubei Depression was exhumed in the Middle Jurassic,and the tectono-thermal evolution was characterized by a rapid uplift during 160-135 Ma,a slow uplift during 135-50 Ma,a rapid uplift during 50-25 Ma,and a slow uplift from 25 Ma to the present.This Cenozoic exhumation was a response to the far field effect of the eastward growth of the Tibetan Plateau.The Cretaceous basins exposed in the surrounding areas of the Huangling paleo-uplift(Zigui basin,Yichang slope,and Huaguoping synclinorium)are foreland basins formed by the bi-directional compression of the Qinling-Dabie orogenic belt and the Xuefengshan intracontinental deformation system.
基金supported by the Open Fund Project of the Key Laboratory of Ionic Rare Earth Resources and Environment,Ministry of Natural Resources(Grant No.2022IREE101)the Young Elite Scientists Sponsorship Program by CAST(Grant No.2022QNRC001)the Geological Investigation Project(Grant Nos.DD20243483,DD20221643).
文摘The pervasively distributed granitoids in South China contributed greatly to regional polymetallic mineralization,including tungsten,tin,copper,gold,rare metals,and rare earth elements(REEs).To ascertain the dynamic backgrounds,rock types and genesis of the parent rocks related to the Early-Middle Jurassic ionic rare earth mineralization,typical deposits at Muzishan,Xiahu,and Zudong were investigated by conducting petrographic,geochronologic,whole-rock geochemical,and Sr-Nd-Pb isotope analyses,which found that the parent rocks from the Muzishan deposit were the A1-type K-feldspar granite(~195 Ma),from the Zudong deposit were the A2-type monzogranite(~171 Ma),and from the Xiahu deposit were the I-type monzogranite(~167 Ma).All the three granitic rocks underwent different degrees of fractionation,with the Xiahu granite experiencing the highest degree,followed by the Zudong granite,and the Muzishan granite undergoing the lowest degree.The Muzishan granite was concluded to be formed under an intraplate extensional tectonic regime influenced by the hotspots or the mantle plume.The Zudong granite was formed in a post-arc extensional setting related to subduction-collision-rollback of the paleo-Pacific Plate,which caused upwelling of the asthenosphere,thinning of the lithosphere,and partial melting of crustal materials.The Xiahu granite was generated under a transitional tectonic setting of extension and compression,triggered by delamination and rollback of the paleo-Pacific Plate.
