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52篇 您的检索式:作者名="DONG YunPeng"
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1Tectonics of South China Continent and its implications显示文摘This paper aims at exploring the tectonic characteristics of the South China Continent(SCC)and extracting the universal tectonic rules from these characteristics,to help enrich the plate tectonic theory and better understand the continental dynamic system.For this purpose,here we conduct a multi-disciplinary investigation and combine it with the previous studies to reassess the tectonics and evolution of SCC and propose that the tectonic framework of the continent comprises two blocks,three types of tectonic units,four deformation systems,and four evolutionary stages with distinctive mechanism and tectonic characteristics since the Neoproterozoic.The four evolutionary stages are:(1)The amalgamation and break-up of the Neoproterozoic plates,typically the intracontinental rifting.(2)The early Paleozoic and Mesozoic intracontinental orogeny confined by plate tectonics,forming two composite tectonic domains.(3)The parallel operation of the Yangtze cratonization and intracontinental orogeny,and multi-phase reactivation of the Yangtze craton.(4)The association and differentiation evolution of plate tectonics and intracontinental tectonics,and the dynamic characteristics under the Meso-Cenozoic modern global plate tectonic regime.ZHANG GuoWei GUO AnLin WANG YueJun LI SanZhong DONG YunPeng LIU ShaoFeng HE DengFa CHENG ShunYou LU RuKui YAO AnPing 2013Science China Earth Sciences2013,56,11:88
2Geochemistry and regional distribution of ophiolites and associated volcanics in Mianlüe suture, Qinling-Dabie Mountains显示文摘Systematic studies of the ophiolites and associated volcanics stretching more than 1500 km from the Derni-Nanping-Pipasi-Kangxian area in the west to the Qingshuihe area of the south Dabie Mountains in the east indicate the existence of a suture zone (the Mianl黣 suture) and a vanished paleo-ocean basin (the Mianl黣 paleo-ocean basin) in the region. From west to east, ophiolitic mlange associations distribute discontinuously along the suture. Rock assem-blages include ophiolite, island arc and oceanic island rock series. The Mianl黣 paleo-ocean basin experienced its major formation and expending episode during the Carboniferous-Permian period. The finding of the suture zone and the paleo-ocean basin is tectonically significant in timing the collision between the North China-Qinling and Yangtze blocks and determining the formation and evolution of the Qinling orogenic belt.LAI Shaocong, ZHANG Guowei, DONG Yunpeng, PEI Xianzhi & CHEN Liang Key Laboratory of Continental Dynamics, Ministry of Education and Department of Geology, Northwest University, Xian 710069, China 2004Science China Earth Sciences2004,47,4:25
3Numerical simulation of the influences of sinker weight on the deformation and load of net of gravity sea cage in uniform flow显示文摘A numerical model for determining fishing net configuration and load is developed, based on the lumped masses method. The model is used to analyze the influences on the net of gravity sea cage by different sinker weights in uniform flow. The net of gravity sea cage is simulated under different current velocities and sinker weights. In order to verify the validity of the numerical results, model test results made by Lader and Enerhaug are cited and compared with the numerical ones. The results of numerical simulation agree well with the experimental ones and the agreement is within an error range of 13% under different velocities and sinker weights. The numerical results indicate that increasing the sinker weight can effectively reduce the net deformation, but the total drag force on the net will increase accordingly. Results will give references for better knowledge of the hydrodynamic behavior of gravity sea cage.LI Yucheng ZHAO Yunpeng GUI Fukun TENG Bin DONG Guohai 2006Acta Oceanologica Sinica2006,25,3:16
4Geochemistry of the subduction-related magmatic rocks in the Dahong Mountains, northern Hubei Province--Constraint on the existence and subduction of the eastern Mianlüe oceanic basin显示文摘The existence and subduction of the eastern Mianl黣 oceanic basin in the south Qinling belt are keys to understand the Qinling orogen. Based on geological mapping, several volcanic slices have been identified in Tumen, Zhoujiawan, Xiaofu and Yuantan areas, which distribute in the northern margin of the Dahong Mountains (DHM), and thrust into the Sanli-gang-Sanyang fault. These slices consist mainly of diabases, basaltic-andesitic lavas, pyroclastic rocks and a minor tuff. The geochemistry of the basalts, andesites,and diabases is characterized by depleting in Nb and Ta, enriching in Th and LILE (e.g.K, Rb, Ba), and undifferentiating in HFSE. These geochemical characteristics suggest that the original magma of these rocks was derived from a mantle wedge above a subduction zone, and formed in an island-arc setting in Carboniferous-early Triassic. Comparing with the ophiolites and island-arc volcanic rocks in Mianxian-Leyang area to the west, it is reasonable to consider that there had been an oceanic basin connecting with the Mianle ancient ocean to the westward, distributing along the south edge of the Tongbai-Dabie block. In view of the ophiolite in Huashan area and these island-arc volcanic rocks along the north of the Dahong Mountains, it is suggested that there had been a plate tectonic evolutionary history with oceanic basin rifting and subduction in this region.DONG Yunpeng, ZHANG Guowei, ZHAO Xia, YAO Anping & LIU Xiaoming The Key Laboratory of Continental Dynamics, Ministry of Education, Department of Geology, Northwest University, Xi抋n 710069,China 2004Science China Earth Sciences2004,47,4:12
5Middle-Late Triassic sedimentation in the Helanshan tectonic belt: Constrain on the tectono-sedimentary evolution of the Ordos Basin, North China显示文摘The Helanshan tectonic belt is located to the west of the Ordos Basin, and separates the Alxa(or Yinshan)Massif to the west from the Ordos block to the east. Triassic sedimentation in the Helanshan tectonic belt records important information about tectono-sedimentary process between the Alxa Massif and the Ordos block. Detailed geological mapping and investigation on the lithological package, sedimentary facies and paleocurrent orientation have been conducted on the Middle to Upper Triassic clastic rocks in the Helanshan tectonic belt. The succession is characterized by upward-fining sequence and comprises coarse grained alluvial-fluvial facies in the lower part as well as deltaic-lacustrine facies in the upper part. Based on detailed study and comparisons on the sedimentary sequence along various sections, the Middle to Upper Triassic strata have been revealed that show clear southeastward-deepening sedimentary differentiation and transgression from southwest to northeast, which are consistent with the southeastward flowing paleocurrent. These features indicate a southeastward-dipping paleogeography in the Helanshan tectonic belt, which was original western part of southeastward orientated fluviallacustrine system in the northwestern proto-Ordos Basin. Further to the east, the Triassic succession in the Ordos Basin displays gradually thickening and alluvial-fluvial system flowed from southeast to northwest, showing a huge thick sedimentary wedge in the western basin margin. Together with the Late Permiane Early Triassic closure of the Paleo-Asian Ocean to the north, the Late Triassic extensional structures and diabase dykes in the Helanshan tectonic belt, all the above sedimentary features could be mostly interpreted as records of an extensional basin correlated to post-collisional collapse of the Central Asian Orogenic Belt.Jiaopeng Sun Yunpeng Dong 2019Geoscience Frontiers2019,10,1:11
6Geochemistry of the E-MORB type ophiolite and related volcanic rocks from the Wushan area, West Qinling显示文摘The mafic-ultramafic assemblages, which thrustthrust into the Wushan-Tangzang boundary fault as some blocks and outcropped in the Yuanyangzhen, Lijiahe, Lubangou and Gaojiahe area, consist mainly of meta-peridotites, gabbros and basalts. The meta-peridotites are characterized by high SiO2 and MgO contents, low ΣREE, as well as their chondrite-normalized rare earth element patterns show some similarities to that of middle oceanic meta-peridotite. The basalts from the Yuanyangzhen, Lijiahe and Lubangou area are characterized by relatively high TiO2 content, low Al2O3 content and Na2O>>K2O. Above all, it is the slight enrichment or flat REE distribution patterns and the unfractionated in HFS elements in the primitive-normalized trace elements distribution patterns that indicate these basalts are similar to that of the typical E-MORB. In comparison, the basalts from the Gaojiahe section are featured by depletion in Nb and Ta contents and enrichment in Th content which show that these were derived from an island-arc setting. From studies of the regional geology, petrology, geochemistry, geo- chronology and all above evidence, it can be suggested that the mafic-ultramafic rocks from the Wushan area are mainly dismembered E-MORB type ophiolite, which represent the fragments of the lithosphere of the Early-Paleozoic Qinling ocean. It is preferred that these rocks were formed in an initial mid-ocean ridge setting during the beginning stage of the oceanic basin spreading. This ophiolite together with the Gaojiahe island-arc basalts shows that there exists an ophiolitic mélange along the Wushan-Tangzang boundary fault, and marks the suture zone after the closure of the Qinling ocean in early Paleozoic.DONG YunPeng ZHANG GuoWei YANG Zhao ZHAO Xia MA HaiYong YAO AnPing 2007Science China Earth Sciences2007,50,z2:9
7The geochemical characteristics,geochronology and tectonic significance of the Carboniferous volcanic rocks of the Santanghu area in northeastern Xinjiang,China显示文摘The Santanghu area is located on the northeastern margin of the Junggar Basin,northern Xinjiang,Northwest China.The Carboniferous volcanic rocks in this area are widely distributed in Kaokesaiergaishan,Santanghu,Daheishan and Naomaohu districts,which are located to the north of the Kalameili Fault.These rocks,sourced from a cognate magma,consist of basic,intermediate,and acidic lavas,and pyroclastic rock.The basic volcanic rocks are enriched with large-ion lithophile elements(LILE),but are relatively depleted in high field strength elements(HFSE),and have an obvious negative Nb-Ta-Ti anomaly.They were most probably derived from a depleted mantle source,and during their ascent,these magmas were not contaminated by the crustal material as they underwent magma crystallization differentiation.Based on the Carboniferous volcanic assemblage and geochemical data,it is apparent that the early Carboniferous volcanism occurred in a subduction-related tectonic setting.New LA-ICP-MS zircon U-Pb analyses constrain the age of the andesite within the volcanic rocks as the early Carboniferous(328.9-331.3 Ma).Combined with the regional geological record,comprehensive analysis of the isotope geochronological data indicates that the subduction of the Junggar Ocean predates the early Carboniferous,and that the Santanghu island arc magmatism was induced by the subduction of the Junggar Ocean in the Carboniferous.LI Wei LIU YiQun DONG YunPeng ZHOU XiaoHu LIU XiaoMing LI Hong FAN TingTing ZHOU DingWu XU XueYi CHEN JunLu 2013Science China Earth Sciences2013,56,8:8
8Sedimentary fill history of the Huicheng Basin in the West Qinling Mountains and associated constraints on Mesozoic intracontinental tectonic evolution显示文摘The Qinling Orogenic Belt is divided commonly by the Fengxian-Taibai strike-slip shear zone and the Huicheng Basin into the East and West Qinling mountains,which show significant geological differences after the Indosinian orogeny.The Fengxian-Taibai fault zone and the Meso-Cenozoic Huicheng Basin,situated at the boundary of the East and West Qinling,provide a natural laboratory for tectonic analysis and sedimentological study of intracontinental tectonic evolution of the Qinling Orogenic Belt.In order to explain the dynamic development of the Huicheng Basin and elucidate its post-orogenic tectonic evolution at the junction of the East and West Qinling,we studied the geometry and kinematics of fault zones between the blocks of West Qinling,as well as the sedimentary fill history of the Huicheng Basin.First,we found that after the collisional orogeny in the Late Triassic,post-orogenic extensional collapse occurred in the Early and Middle Jurassic within the Qinling Orogenic Belt,resulting in a series of rift basins.Second,in the Late Jurassic and Early Cretaceous,a NE-SW compressive stress field caused large-scale sinistral strike-slip faults in the Qinling Orogenic Belt,causing intracontinental escape tectonics at the junction of the East and West Qinling,including eastward finite escape of the East Qinling micro-plate and southwest lateral escape of the Bikou Terrane.Meanwhile,the strike-slip-related Early Cretaceous sedimentary basin was formed with a right-order echelon arrangement in sinistral shear zones along the southern margin of the Huicheng fault.Overall during the Mesozoic,the Huicheng Basin and surrounding areas experienced four tectonic evolutionary stages,including extensional rift basin development in the Early and Middle Jurassic,intense compressive uplift in the Late Jurassic,formation of a strike-slip extensional basin in the Early Cretaceous,and compressive uplift in the Late Cretaceous.LI Wei DONG YunPeng GUO AnLin LIU XiaoMing LIU YiQun ZHA XianFeng ZHANG KuaiLe 2013Science China Earth Sciences2013,56,10:7
9The basic dyke swarms in the Wudang block and its geological significance显示文摘The basic dyke swarms, which have been deformed and metamorphosed, are widespread in the Wudang block. They are geochemically characterized by the continental tholeiites, and their Sm Nd isochron age is (782±164) Ma. All of these indicate that there was an ancient continental block in the Proterozoic and a rifting occurring on this continental block during ±800 Ma.Dingwu Zhou Chengli Zhang Juli Wang Liang Liu Yunpeng Dong Yinyu Liu Song Han 1998Chinese Science Bulletin1998,43,13:6
10Geochronology and geochemistry of mafic dykes in the Helanshan complex: Implications for Mesozoic tectonics in the North China Craton显示文摘The Helanshan tectonic belt(HTB) is a major tectonic divide between the Alxa and Ordos blocks in the North China Craton. The geochronology and petrogenesis of the mafic dykes in the northern HTB are keys to understanding the tectonic evolution of this belt. The mafic dykes, intruded into the Neoarchean-Paleoproterozoic metamorphic basement, are mainly composed of diabase with a mineral assemblage of plagioclase(45%-60%), pyroxene(25%-35%), minor quartz and Fe-Ti oxides. The LA-ICPMS U-Pb analysis of zircon grains from representative dykes yield a weighted mean age of 206 ± 1.9 Ma, which represents the crystallization age of the dyke. The diabases show high contents of Fe_2 O_3~T(11.88-17.55 wt.%), low contents of SiO_2(45.65-50.95 wt.%) and MgO(3.31-5.50 wt.%) with low Mg#(=100×MgO/(MgO + FeO) atomic ration) of 33-44. They are characterized by enrichment of light rare earth elements(LREEs) and large ion lithophile elements(LILEs)(e.g., Rb, Ba and Pb), and slight depletion of high field strength elements(HFSEs). These features suggest that the magma has undergone extensive fractionation of olivine and pyroxene but only minor crustal contamination during its evolution. Their high Sm contents and La/Sm ratios, and low Sm/Yb ratios indicate that magma from which the dykes formed was derived from low degree(about 5%) partial melting of an enriched garnet + spinel lherzolite mantle source. Together with regional geology, these geochemical and geochronological data suggest that the mafic dykes in the HTB were formed in an intracontinental extensional setting during the late Triassic.Zhenghui Li Xiaoming Liu Yunpeng Dong M.Santosh Feifei Zhang Jie Xu 2018Geoscience Frontiers2018,9,6:6
11Characteristics of the island-arc pillow lavas from southeast Yunnan Province, and its tectonic implications for Paleo-Tethys in South China显示文摘Based on the geological mapping, it is suggested that the pillow lavas exposed in Jianshui area in southeastern Yunnan Province are emplaced into the western part of Shizong-Mile faults, the boundary between the Yangtze and Cathaysian blocks, and mainly composed of tectonic massive of basalts and basaltic andsites. The geological and geochemical studies show that these lavas erupted in an island arc tectonic setting, which suggests that there existed the subduction of oceanic crust between the Yangtze and Cathaysian blocks. The paleontological fossils in the sedimentary interlayers between the volcanic rocks indicate that these pillow lavas erupted during Carboniferous-Permian. The geologic and geochemical evidence suggested that there existed an eastern branch of Paleo-Tethys between the Yangtze and Cathaysian blocks in southeastern Yunnan, South China.Yunpeng Dong Bingquan Zhu 2000Chinese Science Bulletin2000,45,8:5
12Relation of Isotope Geochemical Steep Zones with Geophysical Fields and Tectonics in the Junction Area of the Cathaysian,Yangtze and Indochina Plates显示文摘Through lead isotope geochemical mapping in the Yunnan-Guizhou area geochemical steep zones (GSZ) have been established, which clearly reveal the junction relationship of the Cathaysian, Yangtze and Indo-China plates. GSZ are closey related to gravity Mono gradient zones and lithospheric thickness. The GSZ between the Yangtze and Cathaysian plates is consistent with the Shizong-Mile tectonic belt, where island arc basalts are well developed. The Yangtze-Indo-China GSZ is parallel to the Jingdong-Mojiang volcanic belt in rift-island arc environments. The evidence of geology, geophysics and geochemistry all indicates that Cathaysia was subducted towards the Yangtze plate and that the Yangtze plate was underthrust beneath the Indo-China, which took place from the Early Carboniferous to the Early Triassic.ZHU Bingquan Dong Yunpeng CHANG Xiangyang ZHANG Zhengwei 2000Acta Geologica Sinica(English Edition)2000,74,2:5
13Geology and geochemistry of the Bingdaban ophiolitic mélange in the boundary fault zone on the northern Central Tianshan Belt,and its tectonic implications显示文摘The properties and tectonic significance of the fault bound zone on the northern margin of the Central Tianshan belt are key issues to understand the tectonic framework and evolutionary history of the Tianshan Orogenic Belt. Based on the geological and geochemical studies in the Tianshan orogenic belt, it is suggested that the ophiolitic slices found in the Bingdaban area represent the remaining oceanic crust of the Early Paleozoic ocean between the Hazakstan and Zhungaer blocks. Mainly com-posed of basalts, gabbros and diabases, the ophiolites were overthrust onto the boundary fault be-tween the Northern Tianshan and Central Tianshan belts. The major element geochemistry is charac-terized by high TiO2 (1.50%-2.25%) and MgO (6.64%-9.35%), low K2O (0.06%-0.41%) and P2O5 (0.1%-0.2%), and Na2O>K2O as well. Low ΣREE and depletion in LREE indicate that the original magma was derived from a depleted mantle source. Compared with a primitive mantle, the geochemistry of the basalts from the Bingdaban area is featureded by depletion in Th, U, Nb, La, Ce and Pr, and unfrac-tionated in HFS elements. The ratios of Zr/Nb, Nb/La, Hf/Ta, Th/Yb and Hf/Th are similar to those of the typical N-MORB. It can be interpreted that the basalts in the Bingdaban area were derived from a de-pleted mantle source, and formed in a matured mid-oceanic ridge setting during the matured evolu-tionary stage of the Northern Tianshan ocean. In comparison with the basalts, the diabases from the Bingdaban area show higher contents of Al2O3, ∑REE and HFS elements as well as unfractionated incompatible elements except Cs, Rb and Ba, and about 10 times the values of the primitive mantle. Thus, the diabases are thought to be derived from a primitive mantle and similar to the typical E-MORB. The diabases also have slight Nb depletion accompanying no apparent Th enrichment compared with N-MORB. From studies of the regional geology and all above evidence, it can be suggested that the diabases from the Bingdaban area were formed in the mid-oceanic ridge of the Northern Tianshan ocean during the initial spreading stage.DONG YunPeng ZHANG GuoWei ZHOU DingWu LUO JinHai ZHANG ChengLi XIA LinQi XU XueYi LI XiangMin 2007Science China Earth Sciences2007,50,1:5
14Petrogenesis and tectonic implications of Early Cretaceous andesitic-dacitic rocks,western Qinling(Central China):Geochronological and geochemical constraints显示文摘40Ar/39Ar and zircon U-Pb geochronological and whole-rock geochemical analyses for the Laozanggou intermediate-acidic volcanic rocks from the western Qinling orogenic belt,Central China,constrain their petrogenesis and the nature of the Late Mesozoic lithospheric mantle.These volcanic rocks yield hornblende or whole-rock 40Ar/39Ar plateau ages of 128.3-129.7 Ma and zircon U-Pb age of131.3±1.3 Ma.They exhibit SiO2 of 56.86-66.86 wt.%,K2 O of 0.99-2.46 wt.%and MgO of 1.03-4.47 wt.%,with Mg#of 42-56.They are characterized by arc-like geochemical signatures with significant enrichment in LILE and LREE and depletion in HFSE.All the samples have enriched Sr-Nd isotopic compositions with initial 87Sr/86Sr ratios ranging from 0.7112 to 0.7149 andεNd(t)values from 10.2 to 6.3.Such geochemical signatures suggest that these volcanic rocks were derived from enriched lithospherederived magma followed by the assimilation and fractional crystallization(AFC)process.The generation of the enriched lithospheric mantle is likely related to the modification of sediment-derived fluid in response to the Triassic subduction/collision event in Qinling orogenic belt.The early Cretaceous detachment of the lithospheric root provides a reasonable mechanism for understanding the petrogenesis of the Laozanggou volcanic sequence in the western Qinling orogenic belt.Feifei Zhang Peter A. Cawood Yunpeng Dong Yuejun Wang 2019Geoscience Frontiers2019,10,4:3
15SARS-CoV-2 infection aggravates chronic comorbidities of cardiovascular diseases and diabetes in mice显示文摘Background:Cardiovascular diseases(CVDs)and diabetes mellitus(DM)are top two chronic comorbidities that increase the severity and mortality of COVID-19.However,how SARS-CoV-2 alters the progression of chronic diseases remain unclear.Methods:We used adenovirus to deliver h-ACE2 to lung to enable SARS-CoV-2 infection in mice.SARS-CoV-2’s impacts on pathogenesis of chronic diseases were studied through histopathological,virologic and molecular biology analysis.Results:Pre-existing CVDs resulted in viral invasion,ROS elevation and activation of apoptosis pathways contribute myocardial injury during SARS-CoV-2 infection.Viral infection increased fasting blood glucose and reduced insulin response in DM model.Bone mineral density decreased shortly after infection,which associated with impaired PI3K/AKT/mTOR signaling.Conclusion:We established mouse models mimicked the complex pathological symptoms of COVID-19 patients with chronic diseases.Pre-existing diseases could impair the inflammatory responses to SARS-CoV-2 infection,which further aggravated the pre-existing diseases.This work provided valuable information to better understand the interplay between the primary diseases and SARS-CoV-2 infection.Yuanwu Ma Dan Lu Linlin Bao Yajin Qu Jiangning Liu Xiaolong Qi Lei Yu Xu Zhang Feifei Qi Qi Lv Yunpeng Liu Xudong Shi Caixian Sun Jing Li Jie Wang Yunlin Han Kai Gao Wei Dong Ning Liu Shan Gao Jing Xue Qiang Wei Sidan Pan Hong Gao Lianfeng Zhang Chuan Qin 2021Animal Models and Experimental Medicine2021,4,1:3
16Geochemistry and detrital zircon records of the Ruyang-Luoyu groups,southern North China Craton:Provenance,crustal evolution and Paleo-Mesoproterozoic tectonic implications显示文摘Paleo-to Mesoproterozoic sedimentary rocks in the southern margin of the North China Craton(NCC)are represented by the Ruyang and Luoyu groups.We studied the sedimentary rocks from the Yunmengshan and Beidajian formations of the Ruyang Group and the Cuizhuang and Sanjiaotang formations of the Luoyu Group.Detrital zircon grains from these formations have U–Pb age populations of 3.64–3.31 Ga,2.96–2.86 Ga,2.72–2.59 Ga,2.56–2.47 Ga,2.45–2.0 Ga,1.99–1.85 Ga and 1.84–1.65 Ga.The geochemical features of the sedimentary rocks suggest that some of the sediments were sourced from intermediate to felsic magmatic rocks.The age groups of the detrital zircon are roughly consistent with the tectono-thermal events in the southern margin of the NCC.The Hf isotopic compositions of detrital zircon from the sedimentary rocks in Ruyang and Luoyu groups suggest that significant crustal growth and reworking of the NCC took place during the Neoarchean and early-to mid-Paleoproterozoic,while crustal reworking at the Paleoarchean and late-Paleoproterozoic,and crustal growth at the Mesoarchean.We suggest the depositional times of the Ruyang Group and Luoyu Group are constrained to no older than 1.75–1.7 Ga and 1.7–1.65 Ga,respectively.Formation of late-Paleoproterozoic basins related to the strike slip and extrusion tectonics that cross-cut the NCC during the late Paleoproterozoic(<1.75 Ga),and the late Paleoproterozoic sedimentation once isochronous developed in the southern margin of the NCC through the Taihang region of the interior NCC and linked the Yanshan–Liaoxi regions of the northern NCC.Xi-Yao Li Sanzhong Li Tong-Shan Wang Yunpeng Dong Xiao-Guang Liu Shu-Juan Zhao Kun Wang Jiao-Peng Sun Li-Ming Dai Yan-Hui Suo 2020Geoscience Frontiers2020,11,2:3
17Geochemistry, geochronology and Hf isotope of granitoids in the Chinese Altai: Implications for Paleozoic tectonic evolution of the Central Asian Orogenic Belt显示文摘The Chinese Altai in northwestern Xinjiang has numerous outcrops of granitoids which provide critical information on accretionary orogenic processes and crustal growth of the Central Asian Orogenic Belt.Zircon U-Pb ages, Hf-isotopic compositions and whole-rock geochemistry of monzogranite and granodiorites in the Qinghe County are employed to elucidate Paleozoic tectonics of the Chinese Altai. Granodiorites have crystallization ages of 424.6 ± 3.1 Ma(MSWD = 0.23) and 404.0 ± 3.4 Ma(MSWD = 0.18);monzogranite was emplaced in the early Permian with a crystallization age of 293.7 ± 4.6 Ma(MSWD = 1.06). Both granodiorites and monzogranite are I-type granites with A/CNK ratios of 0.92 -0.97 and 1.03 -1.06, respectively. They also show similar geochemical features of high HREE and Y contents, low Sr contents and Sr/Y ratios, as well as enrichment of Cs, Rb, Th and U, and depletion of Nb, Ta, P and Ti.These geochemical features indicate that the monzogranite and granodiorites were formed in an arc setting related to subduction. The gneissic monzogranites display high SiO_2 and K_2 O contents, and belong to the high-K calc-alkaline series. In the chondrite normalized REE distribution pattern, the monzogranite samples exhibit enrichment of LREE with strong negative Eu anomalies(σE u =0.44 -0.53), zircon εHf(t) values from +7.24 to +12.63 and two-stage Hf model ages of 463 -740 Ma. This suggests that the monzogranite was generated from the mixing of pelitic and mantle material. The granodiorite samples are calc-alkaline granites with lower contents of Si O_2 and Na_2 O + K_2 O, higher contents of TiO_2, Fe_2O_3~t, MgO and CaO compared to the monzogranite samples. They also show enrichment of LREE and moderate negative Eu anomalies(σE u= 0.54 =0.81), as well as slightly higher differentiation of LREE than that of HREE. The425 Ma granodiorite has zircon εHf(t) values from -0.51 to +1.98 and two-stage Hf model ages of 1133 -1240 Ma, whereas the 404 Ma granodiorite displays those of +2.52 to +7.50 and 816 -1071 Ma.Geochemistry and zircon Hf isotopic compositions indicate that granodiorites were formed by partial melting of juvenile lower crust. Together with regional geology and previous data, the geochemical and geochronological data of the monzogranite and granodiorites from this study suggest long-lived subduction and accretion along the Altai Orogen during ca. 425 -294 Ma.Dengfeng He Yunpeng Dong Xueyi Xu Junlu Chen Xiaoming Liu Wei Li Xiangmin Li 2018Geoscience Frontiers2018,9,5:3
18Induced pluripotent stem cells:Landscape for studying and treating hereditary hearing loss显示文摘Hearing loss(HL) is one of the most widespread sensory disorders,affecting approximately 1 in 500 newborns.Heritable diseases of the inner ear are the leading causes of prelingual HL.Treating of hereditary HL and understanding its underlying mechanisms remain difficult challenges to otolaryngologists.As stem cells are capable of self-renewal and differentiation,they are ideally suited both for disease modeling and regenerative medicine.Recently,description of induced pluripotent stem cells(iPSCs) has allowed the field of disease modeling and personalized therapy to become far more accessible and physiologically relevant,as iPSCs can be generated from patients of any genetic background.This review briefly describes the advantages of iPSCs technology and discusses potential applications of this powerful biological tool in studying and treating hereditary HL.Tao Peng Yunpeng Dong Ganghua Zhu Dinghua Xie 2014Journal of Otology2014,9,4:2
19Interaction of Irregular Waves with Vertical Breakwater and Characteristics of Secondary Wave Generated by Overtopping显示文摘This study investigated the interaction between irregular waves and vertical breakwater.The main goal was to determine the wave force on the breakwater for different depths,along with the evolution of the secondary wave generated by overtopping.The open source code DualSPHysics was used in the simulation.Wavelet transform was employed to remove the acoustic components from the weakly compressible smoothed particle hydrodynamics pressure solution.The results of the experiments and simulations showed that although the wave height at the low water level(case 2 was smaller than that at the high water level(case 1,the horizontal and uplifting force of case 2 was higher than that of case 1.In case 2,a large impact pressure occurred because of the plunging wave and wave breaking effects.As the water level was close to the breakwater top in case 1,the secondary wave generated by overtopping was studied.Results indicated that wave and breakwater interactions transfer wave energy from the leading wave component to higher harmonics.Two main harmonics were identified in the secondary wave.The first harmonic was the incident peak frequency,which was still the dominant component.During the wave propagation behind the breakwater,the frequencies of harmonics remained unchanged,but the amplitude of the first harmonic showed an obvious change.Under the same wave condition,the first and second harmonics did not change with depth.HAN Xinyu JIANG Yunpeng DONG Sheng 2021Journal of Ocean University of China2021,20,6:2
20An identification model of urban critical links with macroscopic fundamental diagram theory显示文摘Wanli DONG Yunpeng WANG Haiyang YU 2017Frontiers of Computer Science2017,11,1:2
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