The ideology of being ready to make innovation and keeping abreast of the times is a defining feature of the Chinese civilization.IN several of his recent speeches President Xi Jinping stressed that the Chinese civili...The ideology of being ready to make innovation and keeping abreast of the times is a defining feature of the Chinese civilization.IN several of his recent speeches President Xi Jinping stressed that the Chinese civilization has the tradition of discarding the outdated in favor of the new and moving ahead with the times.In exploring a new philosophy that is suitable for governing China in the new era,China draws on its fine traditional culture to find ways of abolishing outdated ideas and making theoretical,practical,and institutional innovations,thus staying abreast of the time to create a better future.展开更多
Three sediment cores were collected in November 2003 from Dagu estuary to Qikou estuary. The main polluted heavy metals in the sediment of tidal zones for the Bohai Bay have been found by analyzing the relationship am...Three sediment cores were collected in November 2003 from Dagu estuary to Qikou estuary. The main polluted heavy metals in the sediment of tidal zones for the Bohai Bay have been found by analyzing the relationship among the contents of heavy metals, the contents of geochemical elements （Fe, AI and Mn） and the size of grain. The dominating contaminative elements in tidal sediments of Bohai Bay are Pb, Zn and Cd. Their contents are higher than the corresponding upper limit of environmental background values and they have very faint correlation with the corresponding contents of geochemical elements and the size of grain, indicating the anthropogenic enrichment. Especially, the preliminary study on the pollution sources and the history of heavy metals in the Dagu estuary has been done using the dated results. The contamination by Zn and Cd also started in the middle 1950s, while the contamination by Pb appeared in the early 1940s. The pollution by Zn and Cd mainly originate from sewage discharge, while the pollution by Pb has many sources, like atmosphere deposition and industrial discharRe.展开更多
Acta Geologica Sinica（English Edition） is indexed by SCI,with the impact factors ranging from 1.5 to 2.15,and also indexed by CA,the Bibliography and Index of Geology（BIG）,Biological Abstracts,and Geographical Abs...Acta Geologica Sinica（English Edition） is indexed by SCI,with the impact factors ranging from 1.5 to 2.15,and also indexed by CA,the Bibliography and Index of Geology（BIG）,Biological Abstracts,and Geographical Abstracts and many others.Internationally,Acta Geologica Sinica（English Edition）has been cooperated with Willey-BlackwellPublishing Corporation,and has all the papers published online.Acta Geologica Sinica（English Edition）has two submission websites at： http：//mc.manuscriptcentral.com/ags for international authors and http：//www.geojournals.cn/ dzxben/ch/index.aspx for Chinese authors. Authors can submit, inquire and download papers at either website.展开更多
Former Chinese leader Deng Xiaoping was known as the chief architect of China’s reform and opening-up drive,and his inspection tour of southern China in 1992 ushered in a new chapter of history characterized by“thre...Former Chinese leader Deng Xiaoping was known as the chief architect of China’s reform and opening-up drive,and his inspection tour of southern China in 1992 ushered in a new chapter of history characterized by“three sustainables”:sustainable economic development,sustainable social stability,and sustainable institutional support and leadership.Fundamentally,the“three sustainables”deftly balanced relationships among economic,social,and political entities.Enterprises represent economic entities,the people are the social entity,and the CPC is the political entity.How exactly has the CPC promoted the modernity of China?展开更多
By using echoes in some sonnets to lines in certain plays, emphasizing those echoes which were not later repeated, and by applying dates to those plays, in 1926 Elizabeth Beckwith tentatively dated a third of the 154 ...By using echoes in some sonnets to lines in certain plays, emphasizing those echoes which were not later repeated, and by applying dates to those plays, in 1926 Elizabeth Beckwith tentatively dated a third of the 154 in the entire sonnets cycle. Her belief was that an unintentional authorial pattern of usage would be less subjective than other approaches to dating the sonnets. Yet, by use of dates from external allusions later applied by Prof. Leslie Hotson and other scholars, this author suggests that it may be possible to extend the total number of datable sonnets to over half of the cycle. However, Beckwith did not use dates for the plays which were later to become a standard dating scheme accepted by most scholars today, and so adjustments of her dates would change the dates she awarded to many of her selected sonnets. This author suggests that even the standard dating scheme is flawed, particularly if Shakespeare was dead when the Sonnets were published in 1609. He suggests another dating regime that meshes quite well with both Beckwith＇s 52 and an additional 27. Thus, the result for the 79 sonnets is to avoid certain problems in the distribution that Beckwith＇s method generated. The net result is what Beckwith termed ＂a skeleton around which the remaining sonnets can be safely built＂, but for over half rather than only a third of the cycle. This author suggests a half＂skeleton＂ is more indicative of the chronology for the whole sonnets cycle than only a third.展开更多
Young people can take on a significant role in shapingChina-U.S.tiesThe last several years have marked difficult times in Sino-American relations;it's been a period of disappointment.For people of Chinese descent ...Young people can take on a significant role in shapingChina-U.S.tiesThe last several years have marked difficult times in Sino-American relations;it's been a period of disappointment.For people of Chinese descent residing in the U.S.,it's also been a time of withdrawal.展开更多
Project name:Dave&Bella Headquarters Location:Binjiang District,Hangzhou Area:7,500 square meters Design company:LYCS Architecture The brief:With its rapid expansion over the past few years,children's apparel ...Project name:Dave&Bella Headquarters Location:Binjiang District,Hangzhou Area:7,500 square meters Design company:LYCS Architecture The brief:With its rapid expansion over the past few years,children's apparel company Dave&Bella enlisted Hong Kong and Hangzhou-based LYCS Architecture to design their brand new multipurpose headquarters.展开更多
Fluctuation history of Midui glacier in the southeastern Tibet since the Little Ice Age(LIA) was reconstructed by the dating of lateral and terminal moraines using tree rings.Four conversions of glacier advance/stabil...Fluctuation history of Midui glacier in the southeastern Tibet since the Little Ice Age(LIA) was reconstructed by the dating of lateral and terminal moraines using tree rings.Four conversions of glacier advance/stabilization to retreat were identified at around 1767,1875,1924 and 1964.The glacier reached its LIA maximum position at 1767.The fluctuations are consistent with those of other glaciers from the Tibetan Plateau,the Rockies and the Alps,suggesting high spatial coherency of glacier fluctuations in the Northern Hemisphere.Comparison with the summer temperature reconstruction in the southeastern Tibetan Plateau indicated that the Midui glacier fluctuation may be related to temperature variation on the centennial timescale.On the decadal scale,the fluctuation could correspond to cold/warm variation with an 8-year lag on average.展开更多
The Malan loess is rich in quartz. The characteristics of its erystal lattice are beneficial to dating of the formation age of Malan loess by using the TL technique. However, in doing so, abundant experimental facts m...The Malan loess is rich in quartz. The characteristics of its erystal lattice are beneficial to dating of the formation age of Malan loess by using the TL technique. However, in doing so, abundant experimental facts must be possessed and a theoretical basis established.展开更多
The dietary polyphenolic compounds resveratrol and quercetin prevent neurodegenerative diseases in experimental models;however, they reach the brain only in nanomolar concentrations in the glucuronidated and sulfated ...The dietary polyphenolic compounds resveratrol and quercetin prevent neurodegenerative diseases in experimental models;however, they reach the brain only in nanomolar concentrations in the glucuronidated and sulfated forms, and not as the aglycone parent form(Pasinetti et al.,2015).展开更多
The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and rev...The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and reviews written by faculty members,researchers and postgraduates in universities,colleges and research institutes all over China and overseas.It reports the latest and the most creative results of important fundamental research in all aspects of chemistry and of developments with significant consequences across sub-disciplines.This journal is sponsored by Jilin University and mandated by the Ministry of Education of P.R.China.展开更多
Deciphering high-pressure granulite-facies metamorphism and anatexis within a collisional orogeny can provide crucial constraints on geodynamic evolution and melt activity during subduction and exhumation.Combining pe...Deciphering high-pressure granulite-facies metamorphism and anatexis within a collisional orogeny can provide crucial constraints on geodynamic evolution and melt activity during subduction and exhumation.Combining petrographic observations,mineral chemistry,REE in Grt-Cpx thermobarometry,and previous work,at least four stages are suggested for the metamorphic evolution of the mafic granulites in the South Altun,including the protolith stage,the high-pressure granulite-facies stage(909-1037℃and 17.3-30 kbar),medium-pressure granulite-facies overprint(9.1-11.9 kbar and 753-816℃),and subsequent late amphibolite-greenschist-facies metamorphism.Zircon U-Pb dating shows that the mafic granulites underwent high-pressure granulite-facies metamorphism at 497.2±3.7 Ma,while the leucosome formed at 498.2±2.9 Ma.Thus,the leucosomes from the host mafic granulite may have been formed at the high-pressure granulite-facies metamorphic event.The characteristics of zircon morphology,mineral inclusions,low Th/U values,HREE enrichment,and negative Eu anomalies indicate that these zircons from the leucosome were formed from the metamorphic melts.The characteristics of whole-rock major and trace elements as well as Hf isotopic features of zircons between the leucosomes and the host mafic granulite indicate that the melt may have been generated by the partial melting of the host mafic granulite.展开更多
Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides i...Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides in elucidating the intricate correlation between structural information and the functioning of the human brain.展开更多
0 INTRODUCTION Uraninite and pitchblende are the most important ore minerals in nearly all types of uranium deposits.Therefore,the U-Pb isotopic system of uraninite and pitchblende are widely used in dating uranium de...0 INTRODUCTION Uraninite and pitchblende are the most important ore minerals in nearly all types of uranium deposits.Therefore,the U-Pb isotopic system of uraninite and pitchblende are widely used in dating uranium deposits.展开更多
The Jianglang Dome has integral tectonostratigraphic units and contains a suite of high-grade stratiform Cu deposits.However,the formation mechanism of this dome and genetic model of Cu mineralization remain a matter ...The Jianglang Dome has integral tectonostratigraphic units and contains a suite of high-grade stratiform Cu deposits.However,the formation mechanism of this dome and genetic model of Cu mineralization remain a matter of debate.The resolution of these problems hinges on the presence of magmatic intrusions in the core.Here,we report bulk geochemical and zircon U-Pb data of a newly discovered syenite intrusion as well as chalcopyrite Re-Os dating results.We aim to explore genesis of the Jianglang Dome,genetic model of the stratiform Cu deposits,and rare metal mineralization potential of the syenite intrusion.The dated syenite sample yields an emplacement age of 207.1±2.0 Ma,which matches post-collisional extension in the Songpan-Ganze Orogen.The syenite rocks have average high(Zr+Nb+Ce+Y)concentrations of 512 ppm,10000.Ga/Al ratios of 3.97,and crystallization temperatures of 827°C,together with low Mg#values of 1.73;they fi t the A-type granitoid defi nition and a crustal origin.Chalcopyrite separates yield a Re-Os isochron age of 207.1±5.3 Ma,which markedly postdates the formation age of their orehosting rocks(the Liwu Group,ca.553 Ma).Our new age determination,together with previous chalcopyrite Re–Os isochron age of ca.151.1 Ma and sulfi de sulfur isotope(δ^(34)S_(V-CDT)=8.7‰–5.6‰)and tourmaline boron isotope(δ^(11)B=−15.47‰to−5.91‰)data,confi rms multistage epigenetic Cu mineralization related to magmatic-hydrothermal fl uids.Compared with regional ca.209–207 Ma fertile granitoids,the studied syenite intrusion shows unevolved and barren affi nities and negligible rare metal mineralization potential.Combined with residual gravity low anomalies in the core of the Jianglang Dome,which suggest a large deepseated granitic batholith,we prefer thermal doming resulting from magma-induced uplift for the nature of this dome.展开更多
1.Objective,The Cretaceous succession is characteristic of the aeolian sedimentary system in the Ordos Basin,which is the major ore-bearing layer for the sandstone-type uranium deposits.Based on the research of paleon...1.Objective,The Cretaceous succession is characteristic of the aeolian sedimentary system in the Ordos Basin,which is the major ore-bearing layer for the sandstone-type uranium deposits.Based on the research of paleontology and magnetostratigraphy,formers believed it belonged to the Early Cretaceous(Huang YB,2010).However,the lack of intrusions or volcanic rocks for isotopic dating results in an unclear formation age for the Lower Cretaceous succession.Recently,tuffs were firstly discovered in the Luohandong Formation in the Zhenyuan area,Gansu Province,located in the southwestern Ordos Basin,China.The LA-ICP-MS zircon U-Pb dating of tuffs was carried out.The new ages can precisely constrain the depositional age of the Luohandong Formation and also provide significant indications for the study of regional volcanic activities,paleoclimate,basin evolution,and tectonic setting.展开更多
The opening of the Central South Atlantic and the consequent formation of the eastern Brazilian continental margin was marked by a complex history of mafic magmatism,carbonate sedimentation,and deposition of a thick s...The opening of the Central South Atlantic and the consequent formation of the eastern Brazilian continental margin was marked by a complex history of mafic magmatism,carbonate sedimentation,and deposition of a thick salt layer.The carbonates underlying the salt layer(pre-salt carbonates)were formed in restricted lacustrine basins.Here,the timing and fluid sources of deposition,diagenetic,and hydrothermal alterations of the pre-salt carbonate rocks are defined through in-situ U-Pb dating,87Sr/86Sr,and trace element analyses of samples from the Santos Basin.The very alkaline nature of the Aptian lake(s)produced characteristically unique and widely distributed carbonate rocks such as Mg-clays with calcite spherulite and calcite crystal shrub limestones transitioning laterally and vertically into travertines formed by hydrothermal pulses during basin evolution.Hydrothermalism caused extensive replacement,dissolution,and calcite cementation.REE+Y PAAS-normalised patterns and 87Sr/86Sr ratios indicate that deposition/eo-diagenesis of the primary carbonates occurred in a lacustrine environment primarily controlled by evaporation,pH,and continental water source,with 2%–10%hydrothermal fluid input.Trace elements and Sr-isotope of travertines and burial diagenetic phases show that they are produced from a hot mixture of mafic/mantle-derived fluids and dissolution/alteration of older carbonate formations.U-Pb dating indicates that carbonate deposition occurred between 124.8±2.6 Ma and 120.0±1.6 Ma,earlier than previously proposed,followed closely by the circulation of hydrothermal fluids.Replacement and cementation ages range from 120.5±2.4 Ma to 80.4±2.4 Ma.展开更多
The ancient Neo-Tethyan region underwent profound tectonic transformations,including the orogenesis of the Xizang Plateau and the westward retreat and ultimate closure of the Neo-Tethyan Ocean.These events significant...The ancient Neo-Tethyan region underwent profound tectonic transformations,including the orogenesis of the Xizang Plateau and the westward retreat and ultimate closure of the Neo-Tethyan Ocean.These events significantly influenced the diversification and biogeography of aquatic animals.However,the impact of these large-scale sea-land shifts on the long-range evolutionary history of terrestrial fauna remains unclear.This study investigated how geological changes in the Neo-Tethyan region shaped the evolutionary trajectories and dispersal patterns of Pholcus sensu lato cellar spiders across the Old World.Molecular dating,ancestral area reconstructions,and diversity analyses were conducted using sequences from seven genes across 234 samples representing 209 species.Results indicated that these spiders originated in the eastern Neo-Tethyan region during the Early Eocene,with their subsequent diversification driven by a series of concomitant geological events.The Eurasian(ER)Group dispersed into Europe following the westward retreat of the Neo-Tethyan Ocean in the Early Miocene,while the African(AF)Group migrated into Africa via the Arabian Plate land bridge following the closure of the Neo-Tethyan Ocean in the Oligocene.The East Asian(EA)Group,which expanded along the southeastern margin of the Himalayas,experienced explosive diversification in response to sustained orogenesis at the Eocene-Oligocene boundary.These findings illustrate how large-scale geological processes and sea-land changes shaped the evolutionary history of terrestrial fauna in the Neo-Tethyan region.展开更多
文摘The ideology of being ready to make innovation and keeping abreast of the times is a defining feature of the Chinese civilization.IN several of his recent speeches President Xi Jinping stressed that the Chinese civilization has the tradition of discarding the outdated in favor of the new and moving ahead with the times.In exploring a new philosophy that is suitable for governing China in the new era,China draws on its fine traditional culture to find ways of abolishing outdated ideas and making theoretical,practical,and institutional innovations,thus staying abreast of the time to create a better future.
基金The National Basic Research Program (973) of China (No. 2002CB412409) and the Hi-Tech Research and Development Program(863) of China(No. 2002AA648010)
文摘Three sediment cores were collected in November 2003 from Dagu estuary to Qikou estuary. The main polluted heavy metals in the sediment of tidal zones for the Bohai Bay have been found by analyzing the relationship among the contents of heavy metals, the contents of geochemical elements （Fe, AI and Mn） and the size of grain. The dominating contaminative elements in tidal sediments of Bohai Bay are Pb, Zn and Cd. Their contents are higher than the corresponding upper limit of environmental background values and they have very faint correlation with the corresponding contents of geochemical elements and the size of grain, indicating the anthropogenic enrichment. Especially, the preliminary study on the pollution sources and the history of heavy metals in the Dagu estuary has been done using the dated results. The contamination by Zn and Cd also started in the middle 1950s, while the contamination by Pb appeared in the early 1940s. The pollution by Zn and Cd mainly originate from sewage discharge, while the pollution by Pb has many sources, like atmosphere deposition and industrial discharRe.
文摘Acta Geologica Sinica（English Edition） is indexed by SCI,with the impact factors ranging from 1.5 to 2.15,and also indexed by CA,the Bibliography and Index of Geology（BIG）,Biological Abstracts,and Geographical Abstracts and many others.Internationally,Acta Geologica Sinica（English Edition）has been cooperated with Willey-BlackwellPublishing Corporation,and has all the papers published online.Acta Geologica Sinica（English Edition）has two submission websites at： http：//mc.manuscriptcentral.com/ags for international authors and http：//www.geojournals.cn/ dzxben/ch/index.aspx for Chinese authors. Authors can submit, inquire and download papers at either website.
文摘Former Chinese leader Deng Xiaoping was known as the chief architect of China’s reform and opening-up drive,and his inspection tour of southern China in 1992 ushered in a new chapter of history characterized by“three sustainables”:sustainable economic development,sustainable social stability,and sustainable institutional support and leadership.Fundamentally,the“three sustainables”deftly balanced relationships among economic,social,and political entities.Enterprises represent economic entities,the people are the social entity,and the CPC is the political entity.How exactly has the CPC promoted the modernity of China?
文摘By using echoes in some sonnets to lines in certain plays, emphasizing those echoes which were not later repeated, and by applying dates to those plays, in 1926 Elizabeth Beckwith tentatively dated a third of the 154 in the entire sonnets cycle. Her belief was that an unintentional authorial pattern of usage would be less subjective than other approaches to dating the sonnets. Yet, by use of dates from external allusions later applied by Prof. Leslie Hotson and other scholars, this author suggests that it may be possible to extend the total number of datable sonnets to over half of the cycle. However, Beckwith did not use dates for the plays which were later to become a standard dating scheme accepted by most scholars today, and so adjustments of her dates would change the dates she awarded to many of her selected sonnets. This author suggests that even the standard dating scheme is flawed, particularly if Shakespeare was dead when the Sonnets were published in 1609. He suggests another dating regime that meshes quite well with both Beckwith＇s 52 and an additional 27. Thus, the result for the 79 sonnets is to avoid certain problems in the distribution that Beckwith＇s method generated. The net result is what Beckwith termed ＂a skeleton around which the remaining sonnets can be safely built＂, but for over half rather than only a third of the cycle. This author suggests a half＂skeleton＂ is more indicative of the chronology for the whole sonnets cycle than only a third.
文摘Young people can take on a significant role in shapingChina-U.S.tiesThe last several years have marked difficult times in Sino-American relations;it's been a period of disappointment.For people of Chinese descent residing in the U.S.,it's also been a time of withdrawal.
文摘Project name:Dave&Bella Headquarters Location:Binjiang District,Hangzhou Area:7,500 square meters Design company:LYCS Architecture The brief:With its rapid expansion over the past few years,children's apparel company Dave&Bella enlisted Hong Kong and Hangzhou-based LYCS Architecture to design their brand new multipurpose headquarters.
基金supported by National Natural Science Foundation of China (Grant Nos.40801033 and 41130529)DFG,German Research Foundation (Grant No.BR1895/21-1)
文摘Fluctuation history of Midui glacier in the southeastern Tibet since the Little Ice Age(LIA) was reconstructed by the dating of lateral and terminal moraines using tree rings.Four conversions of glacier advance/stabilization to retreat were identified at around 1767,1875,1924 and 1964.The glacier reached its LIA maximum position at 1767.The fluctuations are consistent with those of other glaciers from the Tibetan Plateau,the Rockies and the Alps,suggesting high spatial coherency of glacier fluctuations in the Northern Hemisphere.Comparison with the summer temperature reconstruction in the southeastern Tibetan Plateau indicated that the Midui glacier fluctuation may be related to temperature variation on the centennial timescale.On the decadal scale,the fluctuation could correspond to cold/warm variation with an 8-year lag on average.
文摘The Malan loess is rich in quartz. The characteristics of its erystal lattice are beneficial to dating of the formation age of Malan loess by using the TL technique. However, in doing so, abundant experimental facts must be possessed and a theoretical basis established.
基金supported by NIH grants, NINDS R21 NS116720 and NINDS/NIA RF1 NS130681 (to RG and WJM)。
文摘The dietary polyphenolic compounds resveratrol and quercetin prevent neurodegenerative diseases in experimental models;however, they reach the brain only in nanomolar concentrations in the glucuronidated and sulfated forms, and not as the aglycone parent form(Pasinetti et al.,2015).
文摘The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and reviews written by faculty members,researchers and postgraduates in universities,colleges and research institutes all over China and overseas.It reports the latest and the most creative results of important fundamental research in all aspects of chemistry and of developments with significant consequences across sub-disciplines.This journal is sponsored by Jilin University and mandated by the Ministry of Education of P.R.China.
基金financially supported by the Basic Foundation of Tianjin University of Commercethe Fund from the Key Laboratory of Continental Dynamics of Ministry of Natural Resources(J2306)。
文摘Deciphering high-pressure granulite-facies metamorphism and anatexis within a collisional orogeny can provide crucial constraints on geodynamic evolution and melt activity during subduction and exhumation.Combining petrographic observations,mineral chemistry,REE in Grt-Cpx thermobarometry,and previous work,at least four stages are suggested for the metamorphic evolution of the mafic granulites in the South Altun,including the protolith stage,the high-pressure granulite-facies stage(909-1037℃and 17.3-30 kbar),medium-pressure granulite-facies overprint(9.1-11.9 kbar and 753-816℃),and subsequent late amphibolite-greenschist-facies metamorphism.Zircon U-Pb dating shows that the mafic granulites underwent high-pressure granulite-facies metamorphism at 497.2±3.7 Ma,while the leucosome formed at 498.2±2.9 Ma.Thus,the leucosomes from the host mafic granulite may have been formed at the high-pressure granulite-facies metamorphic event.The characteristics of zircon morphology,mineral inclusions,low Th/U values,HREE enrichment,and negative Eu anomalies indicate that these zircons from the leucosome were formed from the metamorphic melts.The characteristics of whole-rock major and trace elements as well as Hf isotopic features of zircons between the leucosomes and the host mafic granulite indicate that the melt may have been generated by the partial melting of the host mafic granulite.
文摘Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides in elucidating the intricate correlation between structural information and the functioning of the human brain.
文摘0 INTRODUCTION Uraninite and pitchblende are the most important ore minerals in nearly all types of uranium deposits.Therefore,the U-Pb isotopic system of uraninite and pitchblende are widely used in dating uranium deposits.
基金supported by the National Natural Science Foundation of China(Nos.41902068,42272106)Young Scholars Development Fund of Southwest Petroleum University(No.201499010083)China Geological Survey Project(Nos.DD20230338,DD20242494)。
文摘The Jianglang Dome has integral tectonostratigraphic units and contains a suite of high-grade stratiform Cu deposits.However,the formation mechanism of this dome and genetic model of Cu mineralization remain a matter of debate.The resolution of these problems hinges on the presence of magmatic intrusions in the core.Here,we report bulk geochemical and zircon U-Pb data of a newly discovered syenite intrusion as well as chalcopyrite Re-Os dating results.We aim to explore genesis of the Jianglang Dome,genetic model of the stratiform Cu deposits,and rare metal mineralization potential of the syenite intrusion.The dated syenite sample yields an emplacement age of 207.1±2.0 Ma,which matches post-collisional extension in the Songpan-Ganze Orogen.The syenite rocks have average high(Zr+Nb+Ce+Y)concentrations of 512 ppm,10000.Ga/Al ratios of 3.97,and crystallization temperatures of 827°C,together with low Mg#values of 1.73;they fi t the A-type granitoid defi nition and a crustal origin.Chalcopyrite separates yield a Re-Os isochron age of 207.1±5.3 Ma,which markedly postdates the formation age of their orehosting rocks(the Liwu Group,ca.553 Ma).Our new age determination,together with previous chalcopyrite Re–Os isochron age of ca.151.1 Ma and sulfi de sulfur isotope(δ^(34)S_(V-CDT)=8.7‰–5.6‰)and tourmaline boron isotope(δ^(11)B=−15.47‰to−5.91‰)data,confi rms multistage epigenetic Cu mineralization related to magmatic-hydrothermal fl uids.Compared with regional ca.209–207 Ma fertile granitoids,the studied syenite intrusion shows unevolved and barren affi nities and negligible rare metal mineralization potential.Combined with residual gravity low anomalies in the core of the Jianglang Dome,which suggest a large deepseated granitic batholith,we prefer thermal doming resulting from magma-induced uplift for the nature of this dome.
基金supported by the Science&Technology Fundamental Resources Investigation Program of China(2022FY101800)the National Science Foundation of China(92162212)the International Geoscience Programme(IGCP 675).
文摘1.Objective,The Cretaceous succession is characteristic of the aeolian sedimentary system in the Ordos Basin,which is the major ore-bearing layer for the sandstone-type uranium deposits.Based on the research of paleontology and magnetostratigraphy,formers believed it belonged to the Early Cretaceous(Huang YB,2010).However,the lack of intrusions or volcanic rocks for isotopic dating results in an unclear formation age for the Lower Cretaceous succession.Recently,tuffs were firstly discovered in the Luohandong Formation in the Zhenyuan area,Gansu Province,located in the southwestern Ordos Basin,China.The LA-ICP-MS zircon U-Pb dating of tuffs was carried out.The new ages can precisely constrain the depositional age of the Luohandong Formation and also provide significant indications for the study of regional volcanic activities,paleoclimate,basin evolution,and tectonic setting.
基金C.Lana and F.F.Alkmim benefit from the Brazilian National Research Council(CNPq)research grants 3073353/2019-2 and 311543/2020-0.C.Lana,F.F.Alkmim,and Maria Eugênia Souza are part of the Instituto GeoAtlântico,a National Institute of Science and Technology,CNPq-Brazil process 405653/2022-0We acknowledge Petrobras’s support during the investigation and permission to publish this study.I.Figueiredo acknowledged the Brazilian Federal Agency for Support and Evaluation of Graduate Education(CAPES)for Master's scholarship 88887.816343/2023-00.
文摘The opening of the Central South Atlantic and the consequent formation of the eastern Brazilian continental margin was marked by a complex history of mafic magmatism,carbonate sedimentation,and deposition of a thick salt layer.The carbonates underlying the salt layer(pre-salt carbonates)were formed in restricted lacustrine basins.Here,the timing and fluid sources of deposition,diagenetic,and hydrothermal alterations of the pre-salt carbonate rocks are defined through in-situ U-Pb dating,87Sr/86Sr,and trace element analyses of samples from the Santos Basin.The very alkaline nature of the Aptian lake(s)produced characteristically unique and widely distributed carbonate rocks such as Mg-clays with calcite spherulite and calcite crystal shrub limestones transitioning laterally and vertically into travertines formed by hydrothermal pulses during basin evolution.Hydrothermalism caused extensive replacement,dissolution,and calcite cementation.REE+Y PAAS-normalised patterns and 87Sr/86Sr ratios indicate that deposition/eo-diagenesis of the primary carbonates occurred in a lacustrine environment primarily controlled by evaporation,pH,and continental water source,with 2%–10%hydrothermal fluid input.Trace elements and Sr-isotope of travertines and burial diagenetic phases show that they are produced from a hot mixture of mafic/mantle-derived fluids and dissolution/alteration of older carbonate formations.U-Pb dating indicates that carbonate deposition occurred between 124.8±2.6 Ma and 120.0±1.6 Ma,earlier than previously proposed,followed closely by the circulation of hydrothermal fluids.Replacement and cementation ages range from 120.5±2.4 Ma to 80.4±2.4 Ma.
基金supported by the Science&Technology Fundamental Resources Investigation Program of China(2023FY100200)National Natural Science Foundation of China(NSFC-32430015,32170461,31872193)。
文摘The ancient Neo-Tethyan region underwent profound tectonic transformations,including the orogenesis of the Xizang Plateau and the westward retreat and ultimate closure of the Neo-Tethyan Ocean.These events significantly influenced the diversification and biogeography of aquatic animals.However,the impact of these large-scale sea-land shifts on the long-range evolutionary history of terrestrial fauna remains unclear.This study investigated how geological changes in the Neo-Tethyan region shaped the evolutionary trajectories and dispersal patterns of Pholcus sensu lato cellar spiders across the Old World.Molecular dating,ancestral area reconstructions,and diversity analyses were conducted using sequences from seven genes across 234 samples representing 209 species.Results indicated that these spiders originated in the eastern Neo-Tethyan region during the Early Eocene,with their subsequent diversification driven by a series of concomitant geological events.The Eurasian(ER)Group dispersed into Europe following the westward retreat of the Neo-Tethyan Ocean in the Early Miocene,while the African(AF)Group migrated into Africa via the Arabian Plate land bridge following the closure of the Neo-Tethyan Ocean in the Oligocene.The East Asian(EA)Group,which expanded along the southeastern margin of the Himalayas,experienced explosive diversification in response to sustained orogenesis at the Eocene-Oligocene boundary.These findings illustrate how large-scale geological processes and sea-land changes shaped the evolutionary history of terrestrial fauna in the Neo-Tethyan region.
