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Oceanic Island Basalts within the West Junggar Ophiolitic Mélanges: Petrogenetic and Tectonic Implications 被引量:3
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作者 YANG Gaoxue LI Yongjun +3 位作者 TONG Lili LI Ganyu SHEN Rui CHAO Wendi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第1期306-306,共1页
Recently, we focused on the Darbut and Karamay ophiolitic m41anges in West Junggar of the Central Asian Orogenic Belt (CAOB, SengOr et al., 1993; Windley et al., 2007; Xiao and Santosh, 2014), and made much progress... Recently, we focused on the Darbut and Karamay ophiolitic m41anges in West Junggar of the Central Asian Orogenic Belt (CAOB, SengOr et al., 1993; Windley et al., 2007; Xiao and Santosh, 2014), and made much progress. This study was supported by the National Nature Science Foundation of China (No. 41303027) and Special Fund for Basic Scientific Research of Central Colleges Project (No. 2014G1271058). The achievements are illustrated as follows. 展开更多
关键词 WEST OIB Petrogenetic and Tectonic Implications langes Oceanic Island Basalts within the West Junggar Ophiolitic M
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The Tectonic Implications of the Hongliuhe-Xichangjing Ophiolitic Mélanges Belt in the Central Region of the Beishan Orogen, NW China——Constrained by the U-Pb Ages of Detrital Zircons of the Metasandstones 被引量:1
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作者 TIAN Jian XIN Houtian +4 位作者 TENG Xuejian DUAN Xiaolong CHENG Xianyu ZHANG Yong REN Bangfang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第4期1256-1275,共20页
The tectonic attributes of different blocks within orogenic belts are of great significance for the study of accretionary processes and the evolution of Earth. The Hongliuhe-Niujianzi-Baiyunshan-Xichangjing ophiolitic... The tectonic attributes of different blocks within orogenic belts are of great significance for the study of accretionary processes and the evolution of Earth. The Hongliuhe-Niujianzi-Baiyunshan-Xichangjing ophiolitic mélange belt(HXOMB) is distributed in the heart of the Beishan Orogen, the Shuangyingshan and Minshui-Hanshan blocks being distributed in the south and north of the HXOMB respectively, and a large number of Early Paleozoic geological units are exposed on the blocks. According to the zircon age populations of the metasandstones in the Baiyunshan area recovered in this paper, when compared with the zircon age populations of the Paleozoic metasandstones reported in the Niujuanzi and Hanshan areas, we found that the metasandstones of the Shuangyingshan Block have age peaks at c. 598 Ma, 742 Ma, 828 Ma, 941 Ma, 990 Ma, 1168 Ma, 1636 Ma, 2497 Ma with non-significant age populations of 1500–1300 Ma, showing a possible affinity with the Tarim Craton;the metasandstones of the Minshui-Hanshan Block have age peaks at c. 606 Ma, 758 Ma, 914 Ma, 1102 Ma, 1194 Ma, 1304 Ma, 1672 Ma with significant age populations of 1500-1300 Ma, showing a possible affinity with the Chinese Central Tianshan Block. Therefore, the HXOMB of the Beishan Orogen is of great significance in plate segmentation, which separates the Tarim Craton in the south and the Chinese Central Tianshan Block in the north. Based on the evolutionary process of the Hongliuhe-Xichangjing ocean in the Beishan Orogen, we believe that break-up and convergence can be recognized as having occurred twice between the Chinese Central Tianshan Block and the Tarim Craton since the Mesoproterozoic in the Beishan area. This was related firstly to the break-up of the Columbia Supercontinent and the convergence of the Rodinia Supercontinent, mainly during the Middle Mesoproterozoic to Early Neoproterozoic, and secondly to the opening and closing of the Hongliuhe-Xichangjing ocean, mainly during the Early Paleozoic. 展开更多
关键词 U-Pb ages of detrital zircons metasandstones Beishan Orogen Hongliuhe-Xichangjing ophiolitic langes belt Tarim Craton Chinese Central Tianshan Block
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A New Understanding on the Emplacement of Ophiolitic Mélanges and Its Tectonic Significance: Insights from the Structural Analysis of the Remnant Oceanic Basin-Type Ophiolitic Mélanges
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作者 WANG Guocan ZHANG Pan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第S01期60-62,共3页
Ophiolites represent on-land fragments of paleooceanic crust and have been recognized as one of the key markers of suture zones.Here,we provide new insights into the emplacement of ophiolitic mélanges based on de... Ophiolites represent on-land fragments of paleooceanic crust and have been recognized as one of the key markers of suture zones.Here,we provide new insights into the emplacement of ophiolitic mélanges based on detailed geological mapping and structural analysis in the West Junggar and Songpan-Ganzi-Bayan Har orogens(Fig.1 and Fig.2).The results show that some ophiolitic mélange belts cannot be regarded as suture zones.The distribution of these ophiolitic mélange belts are usually associated with the structural processes during the closure of remnant oceanic basins.After the remnant-oceanic basin is filled with thick clastic deposit,the oceanic lithosphere material as the base of the remnant basin can be injected into the overlying sedimentary strata through various faultings under the regional compressive stress,forming the remnant oceanic basintype ophiolitic mélange system with dispersive distribution characteristics.Combining with previous researches,the emplacement mechanism of ophiolitic mélanges can be divided into four categories:subduction type which oceanic lithosphere subducted beneath active continental margin,obduction type which oceanic lithosphere obducted over passive continental margin,collision type between two continental lithospheres,and closure type of remnant-oceanic basin(Fig.3).These different types of ophiolitic mélange belts will be superimposed and even re-emplacement by the tectonic processes of post-plate convergence,complicating their distribution.Therefore,identifying the emplacement mechanism type of ophiolitic mélange belts formed in different tectonic processes and backgrounds is of importance for understanding the process of ocean-continental transition and the evolution of orogenic belts. 展开更多
关键词 ophiolitic langes EMPLACEMENT remnant-oceanic basin OROGEN TECTONICS
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The Ophiolitic Mélanges in Strike-slip Fault Zones in West Junggar,Xinjiang,NW China
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作者 GUO Zhaojie CHEN Shi ZHANG Yuanyuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期13-14,共2页
The West Junggar region of western China,located in the far eastern end of the Kazakhstan orocline,occupies the junction of the Siberia,Tarim and Kazakhstan blocks,which is crucial for palinspastic reconstruction of t... The West Junggar region of western China,located in the far eastern end of the Kazakhstan orocline,occupies the junction of the Siberia,Tarim and Kazakhstan blocks,which is crucial for palinspastic reconstruction of the CAOB.The principal rock assemblages in West Junggar include Paleozoic ophiolitic mélanges and a thick,undeformed Upper Devonian–Lower Carboniferous sedimentary succession as the boundary of the mélanges,both of which are intruded by sub-circular Upper Carboniferous granitoid plutons and intermediate-basic-mafic dykes.On the basis of the sedimentary structures like cross bedding and convolute bedding and the geochronology data,the Upper Devonian–Lower Carboniferous sedimentary successions were identified as the Tailegula,Baogutu,and Xibeikulasi formations from the bottom up,which is an apparent shallowing-upwards ocean basin fill succession,from radiolarian cherts through 2000 meters of flysch to a more neritic Baogutu Formation to a fluvial Xibeikulasi Formation.At the bottom of the Tailegula Formation there is a peperite-bearing unit:a succession of extrusive mafic rock,mainly basaltic lava,with interbeds or blocks of sedimentary rocks including carbonate,radiolarian chert,calcareous siltstone and minor fine-grained tuffaceous sandstone.Peperites in the Tailegula are thickest and best developed as the type section.Four types of peperites were identified based on of the volcanic clast shapes and sediment-matrix properties in Tailegula:(1)arbonatesediment-hosted fluidal peperites,(2)sandstone-hosted fluidal peperites,(3)tuff-hosted mixed fluidal and blocky peperites and(4)carbonate-sediment-hosted blocky peperites.Zircon LA-ICP-MS U-Pb dating of a tuff lens enclosed by lava showed that the peperites formed in the Late Devonian(ca.364 Ma).The widespread peperitebearing succession in the Tailegula Formation is of variablethickness at different sites in West Junggar,such as the Tailegula,Baijiantan,Kalaxiuka,Saertuohai,Dagun,west of the Akebastaw granite and Shinaizha areas.The peperite-bearing unit is generally undeformed in contrast to the highly deformed slices of ophiolite,and is continuously distributed as a stratigraphic section regionally on either side of the Darbut and Baijiantan ophiolitic belts.It can be taken as a mark layer to demonstrate the existence of a shallow remnant ocean basin from the end of Devonian in West Junggar,which is an important component of oceanic crust in the remnant ocean basin.Peperite,underlying Devonian or earlier oceanic crust developed in the spreading process of the ocean basin,and overlying Carboniferous remnant ocean basin-fill succession constitute the complete evolution sequence of the remnant ocean basin.The Darbut and Baijiantan ophiolitic belts should not be interpreted as significant plate boundaries and represent the underlying ocean crust uplifted along tectonic lineaments within a continuous shallow remnant ocean basin.The Baijiantan and Darbut ophiolites are both steep fault zones(>70°)of serpentinite mélange,in contact on either side with regionally distributed and undeformed Upper Devonian–Lower Carboniferous ocean-floor peperitic basalts and overlying sedimentary successions.Ultramafic rocks is serpentinized and foliated to form the matrix of mélange.Some small blocks of peridotite are mylonitic and strongly foliated.Blocks of gabbro generally underwent prehnitization,epidotization and chloritization and many are metasomatized to rodingite.Pods of medium to fine grained amphibolites are encased in serpentinite and display relict gabbroic textures and amphibolite-facies assemblages.The Baijiantan ophiolitic mélange also includes amphibolite brecciasconsistingofcentimeter-sizedmylonitic amphibolite clasts embedded within a serpentinite matrix.Basalt lavas cropping out in the Baijiantan ophiolitic mélange are of two types:type 1 and type 2 lavas.The type1 lavas occur within the fault zones as small blocks withinthe matrix of ultramafic rocks,tectonically juxtaposed against other rocks.The type 2 basalt lava came from the peperite-bearing unit.Besides the ultramafic rocks,gabbros,and basalt lavas,the other supracrustal rocks in the ophiolitic mélange include sandstone,chert,tuff,and very rare limestone.Sandstones predominate and most of them are tuffaceous;their characteristics are consistent with the sandstones from surrounding Lower Carboniferous sedimentary formations.Sandstone blocks within the mélanges also have detrital zircon age distributions(300-400 Ma)and characteristics similar to surrounding Carboniferous sediments.The rock assemblages in the mélanges indicate the ophiolitic mélanges consist of locally derived rocks,in contrast to conventional ophiolitic mélanges.The ophiolitic mélanges show classic structural features of strike-slip shearing regimes,including subhorizontal slickenside lineations(<20°),consistent steeply dipping foliation(>75°)in the matrix,and elongated shapes of blocks aligned parallel to the shear zone.Consistent shear-sense indicators including slip-fiber lineations,Riedel shears,asymmetric blocks,shear band cleavages and veins indicate a horizontal sinistral sense of movement.The occurrence of the amphibolite and ultramafic mylonite in the mélanges probably record early,deep-seated strike slip,indicating that the fault zones extended downward through the oceanic crust.The amphibolite-facies metamorphism then was superimposed by brittle deformation at a shallow level to form fault breccias during the mélange formation.So the ophiolitic mélanges originated from crustal-scale sinistral strike-slip fault zones,not as major plate boundaries or subduction-suture zones.The youngest units of the mélanges are the deformed blocks of Lower Carboniferous basin-fill sedimentary rocks,indicating that the ultimate formation of the mélanges was after deposition of the Lower Carboniferous strata(detrital zircon age modes:320-330 Ma),but before the age of the intruding granite and the dike cutting the mélanges(~310 Ma).Based on above discussions and taking into consideration of the previous studies,a tectonic evolution scenario is proposed for the Devonian to Carboniferous in the West Junggar region.In the middle Devonian or earlier(>390Ma),a paleo-ocean basin existed,stretching across North Xinjiang from Darbut-Baijiantan area in West Junggar to the Kalamaili area in East Junggar.This basin was most likelyaback-arcbasinrelatedtothe Boshchekule–Chengiz–Yemaquan arc.Subduction ended in thepaleo-oceanbasinrepresentedbythe Hongguleleng-Kujibai-Armantai ophiolite belt by late Devonian(375-360 Ma),leading to slab break-off and upwelling of asthenosphere under the remnant ocean basin,which induced The OIB-like basalts in West Junggar.The oceanic basin started to receive sufficient sediment deposition into which OIB-like basalts flows could bulldoze to form the regional distributed peperites(~360 Ma).A little later,in the early Carboniferous(~340 Ma),continent-continent collision took place between the Junggar block and the Yemaquan arc,and Kalamaili ophiolite obduction occurred in the eastern part of Junggar block.The remnant ocean basin was preserved in the western part of the Junggar Block.Accompanying the relative motion between Junggar block and ocean basin in West Junggar during collision,a series of NW trending sinistral strike-slip faults were triggered and activated parallel to the western boundary of the Junggar block.During the late stage of the Early Carboniferous(~320 Ma),the remnant ocean basin was almost filled with sediments.The collision between the Yili and Junggar blocks at the beginning of the late Carboniferous reactivated the strike-slip faults,which disrupted the oceanic crust and basin-fill successions and caused diapirs of serpentinite to form the Baijiantan and Darbut ophiolitic mélanges.The emplacement of Upper Carboniferous(~310 Ma)stitching A-type granitoid plutons indicates the evolutionary history of the remnant ocean basin and strike-slip fault zone ophiolitic mélanges terminated by that time. 展开更多
关键词 WEST langes in Strike-slip Fault Zones in West Junggar XINJIANG NW China The Ophiolitic M
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Timing and mechanism of opening the Neo-Tethys Ocean:Constraints from mélanges in the Yarlung Zangbo suture zone 被引量:1
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作者 Tong LIU Chuanzhou LIU +4 位作者 Fuyuan WU Wenbin JI Chang ZHANG Weiqi ZHANG Zhenyu ZHANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2023年第12期2807-2826,共20页
The evolution and final closure of the Neo-Tethys Ocean are one of the most important geological events that have occurred on Earth since the Mesozoic.However,the evolution of the Neo-Tethys is not well constrained,in... The evolution and final closure of the Neo-Tethys Ocean are one of the most important geological events that have occurred on Earth since the Mesozoic.However,the evolution of the Neo-Tethys is not well constrained,in particular whether its opening occurred in the Permian or the Triassic and whether a plume was involved with its opening or not.In this study,we present geochronological and geochemical data for mafic igneous rocks in mélanges along the Yarlung Zangbo suture zone(YZSZ)in southern Xizang to constrain the timing and mechanism of opening the Neo-Tethys Ocean.Based on field observations,the YZSZ mélanges can be divided into three segments.The western(west of Zhongba)and eastern(Sangsang-Renbu)segments are composed of ocean plate stratigraphy representing accretionary complexes that formed during subduction of Neo-Tethyan oceanic lithosphere beneath the southern margin of the Asian continent.Mélanges in the central segment(Zhongba-eastern Saga)typically have a siliciclastic matrix,and represent Tethyan Himalayan strata that were structurally mixed with the southern margin of the Asian continent.Based on our and previously published geochemical data,the mafic rocks in the YZSZ mélanges are ocean island basalt(OIB)-like,with ages in the Late Permian-Middle Triassic,the Middle-Late Jurassic,and the Early Cretaceous,respectively.An OIB-like block with an age of ca.253 Ma is identified from the Zhongba mélanges in the western segment,and it is the oldest OIB lithology yet identified in the YZSZ mélanges related to the evolution of the Neo-Tethys Ocean.Geochemical features indicate that this OIB-like block is distinct from typical OIBs and would be formed during continental rifting to incipient seafloor spreading.In the framework of plate divergent-convergent coupling systems and based on literature data for early Middle Triassic seamounts,radiolarian cherts,and normal mid-ocean ridge basalt-like oceanic crust,we conclude that opening of the Yarlung Zangbo Neo-Tethys Ocean would mainly occur at~250–243 Ma in the Early Triassic,not later than the early phase of Middle Triassic.In addition,a mantle plume was not involved in opening the Yarlung Zangbo Neo-Tethys Ocean.On the other hand,we have also identified a suite of ca.160 Ma OIB-like basaltic sills from the Bainang mélanges in the eastern segment,which is the same age as the OIB lithologies previously reported in the Zhongba mélanges.Based on the sill-like occurrence and absence of plume-related rock associations in this region,the Bainang OIB-like rocks might result from Middle-Late Jurassic continental rifting in northern Gondwana.Magmatism related to this tectonic event is preserved in both the YZSZ mélanges and Himalayan strata,but its tectonic significance requires further investigation.Based on this study of the YZSZ mélanges and the previous studies of YZSZ ophiolites,Gangdese belt igneous rocks,and sedimentary rocks,we have reconstructed the entire Wilson Cycle of the Yarlung Zangbo Neo-Tethys Ocean,mainly involving continental rifting and ocean opening,subduction initiation,ultraslow-spreading ridge-trench conversion,subduction re-initiation,and oceanic closure and initial India-Asia collision for the tectonic emplacement of ophiolites.These processes were associated not only with magmatic flare-ups and lulls in the Gangdese belt but also with two stages of ophiolite obduction.Our data therefore provide new insights into the evolution of the Yarlung Zangbo Neo-Tethys Ocean and related Tethyan geodynamics. 展开更多
关键词 Neo-Tethys Ocean Wilson Cycle Yarlung Zangbo suture zone MÉLANGE Ocean island basalt Tethyan geodynamics
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Cornelia de Lange综合征患者临床特征及其遗传学分析2例报告及文献复习
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作者 蔡美娇 陈佳燕 +3 位作者 马小敏 黄燕茹 张剑 葛运生 《吉林大学学报(医学版)》 北大核心 2025年第2期501-507,共7页
Cornelia de Lange综合征(CdLS)是一种罕见的先天性畸形疾病,其典型特征包括生长受限、智力迟钝、颅面异常和多毛症等。本研究报道2例CdLS患者,对其临床表现和基因变异特点进行总结,并结合相关文献进行复习。患者1,女性,5岁,因生长发育... Cornelia de Lange综合征(CdLS)是一种罕见的先天性畸形疾病,其典型特征包括生长受限、智力迟钝、颅面异常和多毛症等。本研究报道2例CdLS患者,对其临床表现和基因变异特点进行总结,并结合相关文献进行复习。患者1,女性,5岁,因生长发育缓慢就诊。查体多毛,一字眉,牙齿小、稀疏,前胸、后背可见血管瘤(约2 cm×2 cm),语言发育迟缓,智力落后;身高98 cm [≤-2标准差(SD)],体质量15 kg (-2SD~-1SD),头围46 cm (-3SD~-2SD);脑核磁共振成像(MRI)平扫显示左侧侧脑室侧后角和双侧侧脑室三角略扩大,双侧上颌窦和筛窦黏膜轻度增厚,心脏彩超显示二、三尖瓣轻度反流。患者2,女性,1个月,生后气促,软腭裂,吞咽困难及三凹征阳性,双手小、左手通贯掌、右手第5指短小,右侧髋关节外展受限,双足内翻,右眼底白斑。1个月时超声显示三尖瓣轻度反流,房间隔卵圆孔未闭。2d时脑MRI平扫显示纵裂池及天幕可见少许斑片状低信号影,少量蛛网膜下腔出血,双侧上颌窦、筛窦和中耳乳突少量积液。染色体核型分析未见明显结构及数目异常。全外显子组测序检测,患者1存在NIPBL基因c.6653_6655del杂合变异,患者2存在NIPBL基因c.337C>T杂合变异,父母均未检测到该变异。NIPBL基因变异是CdLS患者的主要遗传学病因,基因变异c.337C>T的鉴定扩展了NIPBL基因的变异谱系,为研究CdLS患者致病性基因变异提供了新证据。 展开更多
关键词 Cornelia de Lange综合征 NIPBL基因 基因变异 变异谱系
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HDAC8基因突变所致Cornelia de Lange综合征1例并文献复习
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作者 郝晓轲 李朝阳 +3 位作者 赵晨玥 孙泽钫 张雯娟 王亮亮 《中国儿童保健杂志》 北大核心 2025年第5期576-580,共5页
Cornelia de Lange综合征(Cornelia de Lange syndrome,CdLS)在1933年由荷兰儿科医生Cornelia首次描述,该病是一种伴有多系统发育异常的遗传缺陷综合征,呈常染色体显性或X连锁显性方式遗传,发病率介于1/10000~1/30000活产新生儿,常表现... Cornelia de Lange综合征(Cornelia de Lange syndrome,CdLS)在1933年由荷兰儿科医生Cornelia首次描述,该病是一种伴有多系统发育异常的遗传缺陷综合征,呈常染色体显性或X连锁显性方式遗传,发病率介于1/10000~1/30000活产新生儿,常表现为成比例的身材矮小、宫内及出生后发育迟缓、特定的面部特征、多器官系统畸形(特别是心脏、胃肠道和肌肉骨骼系统)以及认知和行为方面的异常等。该病常见的突变基因有NIPBL、SMC1A、SMC3、RAD21、BRD4、HDAC8和ANKRD11,所有这些基因表达的蛋白都参与组成黏连蛋白复合物或影响其调节功能[1-2]。本团队对1例CdLS患儿及其家系成员进行基因突变检测,发现患儿携带HDAC8基因c.111+3A>T新发突变,既往未见报道,并统计中国目前报道的HDAC8基因突变所致CdLS患者基因型及临床表现,具体报告如下。 展开更多
关键词 Cornelia de Lange综合征 HDAC8基因 突变 遗传缺陷综合征
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The replacement Global Stratotype Section and Point(GSSP)of the Telychian Stage of the Llandovery Series,Silurian System,at El Pintado(Spain)
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作者 David K.Loydell Juan Carlos Gutiérrez-Marco +1 位作者 Petr Štorch Jiří Frýda 《Episodes》 2025年第2期199-211,共13页
The El Pintado 1 Silurian section in Seville Province,Spain,described by Loydell et al.(2015),has been ratified by the IUGS as the replacement GSSP for the base of the Telychian Stage,to replace the Cefn Cerig quarry ... The El Pintado 1 Silurian section in Seville Province,Spain,described by Loydell et al.(2015),has been ratified by the IUGS as the replacement GSSP for the base of the Telychian Stage,to replace the Cefn Cerig quarry section in the Llandovery area of Wales,which was found to be within a sedimentary mélange and therefore not a continuous section.No section other than El Pintado 1 has been found to be continuously fossiliferous across the Aeronian/Telychian boundary. 展开更多
关键词 Silurian System el pintado sedimentary m lange silurian section Telychian Stage cefn cerig quarry section Llandovery Series El Pintado
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Exploring the Failure Mechanism of the Baige Landslide via Field Observations and Physical Model Tests
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作者 Peng Cao Huiming Tang +4 位作者 Meng Wang Kun Fang Minhao Miao Jianhui Deng Xinming Wu 《Journal of Earth Science》 2025年第4期1682-1699,共18页
In 2018,a catastrophic high-altitude landslide occurred at Baige,located within the tectonic suture zone of the Upper Jinsha River.The failure mechanism of this event remains poorly understood.This study aims to eluci... In 2018,a catastrophic high-altitude landslide occurred at Baige,located within the tectonic suture zone of the Upper Jinsha River.The failure mechanism of this event remains poorly understood.This study aims to elucidate the deformation characteristics and failure mechanism of the Baige landslide by employing a comprehensive methodology,including field geological surveys,analysis of historical remote sensing imagery,high-density electrical resistivity surveys,and advanced displacement monitoring.Additionally,the physical modeling experiments were conducted to replicate the unique failure modes.The findings propose a novel perspective on the failure mechanism of the Baige landslide,which involves two critical stages:first,the brittle shear zone bypasses and fails at the lower locked segment,and second,the failure of the upper locked segment,combined with the shear zone's impact on the lower locked segment,triggers overall slope instability.Physical modeling experiments revealed a transition from initial acceleration to a rapid acceleration phase,particularly marked by a significant increase in velocity following the failure of the upper locked segment.The intensity of acoustic emission signals was found to correlate with the failure of the locked segments and the state of particle collisions post-failure.It offers new insights into the failure mechanisms of tectonic mélange belt large-scale landslides in suture zones,contributing to the broader field of landslide research. 展开更多
关键词 Baige landslides Jinsha River tectonic mélange belt failure pattern physical model experiments mechanisms
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Locking Effect of the Inhomogeneous Tectonic Lenticular Rock Mass in the Internal Geological Structure of the Baige Landslides
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作者 Peng Cao Huiming Tang +3 位作者 Kun Fang Jianhui Deng Zongliang Li Xinming Wu 《Journal of Earth Science》 2025年第4期1663-1681,共19页
In 2018,Baige,Xizang,witnessed two consecutive large-scale landslides,causing significant damage and drawing widespread attention.From March 2011 to February 2018,the Baige landslide exhibited a 50-m displacement with... In 2018,Baige,Xizang,witnessed two consecutive large-scale landslides,causing significant damage and drawing widespread attention.From March 2011 to February 2018,the Baige landslide exhibited a 50-m displacement without complete failure,culminating in a collapse in October 2018.The mechanisms behind its resistance to failure despite substantial deformation and the influence of the complex geo-structure within the tectonic mélange belt remain unclear.To address these questions,this study utilized a multidisciplinary approach,integrating on-site geological field mapping,surface deformation monitoring,multielectrode resistivity method,and deep displacement analysis.The aim was to evaluate the impact of the intricate geo-structure within the tectonic mélange belt on the Baige landslide events.Findings reveal that the landslide's geo-structure consists of structurally fractured,mesh-like rock masses,including heterogeneous lenticular rock masses and intermittent brittle shear zones distributed around the lens-shaped rock masses.The study underscores that the inhomogeneous and weakly deformed lenticular rock masses function as natural locked segments,governing the stability of the Baige landslide.Specifically,the relatively intact and hard granodiorite porphyry play a crucial role in locking the landslide's deformation.Deep displacement analysis indicates that the brittle shear zones act as the sliding surfaces.The progressive destruction of the locked segments and the gradual penetration of brittle shear zones,driven by gravitational potential energy,contribute to the landslide occurrence.This research provides critical insights into the formation mechanisms of large-scale landslides within tectonic mélange belts. 展开更多
关键词 Baige landslides Jinsha River tectonic mélange belt internal geological structure macro-meso-micro scales rock mass strength heterogeneity locked effect mechanisms
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Late Triassic back-arc basin of the Ganzi-Litang Ocean:constraints from SSZ-type basalt in the Litang area,Eastern Tibet
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作者 Songtao Yan Ailing Ding +5 位作者 Lidong Zhu Meng Qin Tao Liu Jie Wang Chongyang Xin Qingsong Wu 《Episodes》 2025年第3期241-254,共14页
The genesis and tectonic setting of Late Triassic volcanic rocks in the Ganzi–Litang ophiolitic mélange belt have long been a subject of contention.To elucidate these ambiguities,comprehensive petrological,geoch... The genesis and tectonic setting of Late Triassic volcanic rocks in the Ganzi–Litang ophiolitic mélange belt have long been a subject of contention.To elucidate these ambiguities,comprehensive petrological,geochemical,zircon U-Pb geochronological,and Sr-Nd isotopic analyses were conducted on the Luexigou basalts in the Litang area.This investigation has newly delineated a typical volcano-sedimentary sequence indicative of a mid-ocean ridge,with basalts dated to 215±3 Ma.These basalts exhibit geochemical characteristics akin to E-MORB,displaying relatively flat distribution patterns for rare earth elements and trace elements.They are notably depleted in high-field-strength elements(such as Nb and Ta),similar to volcanic arc basalts. 展开更多
关键词 ophiolitic m lange belt back arc basin Late Triassic Litang area late triassic volcanic rocks SSZ type basalt geochemical chara Ganzi Litang Ocean
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鱇白鱼的生物学及其种群衰减原因分析 被引量:11
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作者 李再云 陈银瑞 杨君兴 《淡水渔业》 CSCD 北大核心 2003年第1期26-27,共2页
关键词 鱇Lang白鱼 生物学特性 种群衰减 种间竞争 种间平衡 银鱼灯光诱捕
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6~18GHz脊波导宽带功率合成放大器 被引量:5
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作者 党章 朱海帆 黄建 《微波学报》 CSCD 北大核心 2019年第4期21-25,41,共6页
提出一种不通过波导脊背与微带导带接触来实现脊波导-微带射频信号过渡的新型电路,具有工作频带宽、插入损耗小、电性能稳定等优点,非常适合工程应用。通过对该非接触式脊波导-微带过渡与Lange电桥进行理论分析与仿真计算,提出了一种可... 提出一种不通过波导脊背与微带导带接触来实现脊波导-微带射频信号过渡的新型电路,具有工作频带宽、插入损耗小、电性能稳定等优点,非常适合工程应用。通过对该非接触式脊波导-微带过渡与Lange电桥进行理论分析与仿真计算,提出了一种可覆盖C/X/Ku频段的宽带功率合成方法,并按照该方案在6~18 GHz频段内设计了一种以脊波导为射频端口的高效率2路功率合成放大器。实测结果表明,6~18 GHz频率范围内的无源合成效率高于87%。采用该电路将典型输出功率12 W的2只MMIC的输出功率合成,在6~18 GHz频率范围内得到了高于20 W的饱和功率输出,附加效率最高可达28.9%。该宽带功率合成放大器以脊波导为接口,不但功率容量大,且便于采用脊波导功率合成器进行高效率二次合成,为6~18 GHz更大输出功率的固态功放研制提供了解决方案。 展开更多
关键词 非接触式脊波导-微带过渡 Lange电桥 宽带 高效率 功率合成
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HDAC8基因变异所致Cornelia de Lange综合征1例报告 被引量:2
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作者 董燕 史晓依 +5 位作者 徐瑞娟 杜开先 贾天明 王丽君 李肖 宋盼盼 《临床儿科杂志》 CAS CSCD 北大核心 2021年第1期51-54,共4页
目的探讨Cornelia de Lange综合征(CdLS)的临床表型及基因型特点。方法回顾分析1例确诊CdLS患儿的临床资料,并总结分析国内已报道病例的情况。结果女性患儿,1岁2月龄,有特殊外貌,智力及运动发育落后,合并四肢畸形及听力异常。基因检测... 目的探讨Cornelia de Lange综合征(CdLS)的临床表型及基因型特点。方法回顾分析1例确诊CdLS患儿的临床资料,并总结分析国内已报道病例的情况。结果女性患儿,1岁2月龄,有特殊外貌,智力及运动发育落后,合并四肢畸形及听力异常。基因检测发现患儿HDAC8基因c.675C>A(p.Y 225X)存在新发杂合无义变异,根据ACMG指南预测为致病性变异,确诊CdLS。通过对万方、维普、中国知网及PubMed数据库搜索,发现国内报道CdLS病例46例。其中26例行基因检查,20例(76.9%)存在NIPBL基因变异,3例(11.5%)HDAC8基因变异,1例(3.8%)SCM1A基因变异,2例未发现与临床吻合的致病性基因变异,表型各异。结论CdLS患儿存在特殊外貌、生长发育迟缓、多器官受累、听力障碍,多数可通过典型临床表型诊断,基因检测有助于非典型患者的早期诊断。 展开更多
关键词 HDAC8基因 新发突变 Cornelia de Lange综合征 临床分析
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一种基于Lange耦合器的S波段小型化集成功放 被引量:2
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作者 林川 杨斌 +1 位作者 苑小林 高群 《固体电子学研究与进展》 CAS CSCD 北大核心 2012年第6期565-568,共4页
设计了一种全部采用国产芯片研制的小型化集成功放模块。该模块采用一种全新的结构模式,通过Lange耦合器将GaAs MMIC单片、单电源GaAs功率芯片和硅功率芯片混合集成,使得其体积比同等性能的功率放大器减小。测试结果表明,在工作电压36V... 设计了一种全部采用国产芯片研制的小型化集成功放模块。该模块采用一种全新的结构模式,通过Lange耦合器将GaAs MMIC单片、单电源GaAs功率芯片和硅功率芯片混合集成,使得其体积比同等性能的功率放大器减小。测试结果表明,在工作电压36V、脉宽300μs、占空比10%的测试条件下,2.7~3.1GHz或3.1~3.4GHz带内输出功率均能达到50W,36V电源效率大于40%。 展开更多
关键词 小型化 LANGE耦合器 功放 集成
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S波段小型化大功率功放模块设计与实现 被引量:5
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作者 刘登宝 王卫华 《现代雷达》 CSCD 北大核心 2023年第3期84-87,共4页
现代S波段相控阵雷达对T/R组件发射通道小型化和大功率的需求越来越高。GaN功率器件具有高功率密度、高效率和突出的热属性,采用GaN功率器件来构建功放模块是实现小型化和大功率的首选方案。文中采用载片式内匹配GaN功率放大器、GaN MMI... 现代S波段相控阵雷达对T/R组件发射通道小型化和大功率的需求越来越高。GaN功率器件具有高功率密度、高效率和突出的热属性,采用GaN功率器件来构建功放模块是实现小型化和大功率的首选方案。文中采用载片式内匹配GaN功率放大器、GaN MMIC功放芯片、Lange电桥及微组装工艺,研制出一种S波段功放模块,体积小,重量轻,在10%带宽内,实现了输出功率大于150 W、功率增益超过35 dB、效率超过50%的性能指标,相较于基于分立封装功率管构建的功放模块,重量和体积上的优势巨大,可广泛应用于现代轻型化相控阵雷达。 展开更多
关键词 功放模块 GaN功率器件 小型化 大功率 载片式 内匹配 Lange电桥
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儿童发育障碍相关性疾病 被引量:8
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作者 麻宏伟 黎芳 《中国儿童保健杂志》 CAS 2017年第10期973-977,共5页
在发育儿科门诊中,经常会遇到一些伴有特殊面容或特殊行为的发育障碍儿童,临床医生可以像掌握唐氏综合症特殊面容那样,通过识别这些发育障碍儿童的特殊面容或行为疑诊为某种疾病。伴有特殊面容或行为的常见发育障碍疾病包括William综合... 在发育儿科门诊中,经常会遇到一些伴有特殊面容或特殊行为的发育障碍儿童,临床医生可以像掌握唐氏综合症特殊面容那样,通过识别这些发育障碍儿童的特殊面容或行为疑诊为某种疾病。伴有特殊面容或行为的常见发育障碍疾病包括William综合征,Cornelia de Lange综合征,脆性X综合征,Rett综合征,DiGeorge综合征及Prader-Willi综合征。对于以多动症为主诉的患儿,应注意William综合征,该病除了有多动的表现之外,还伴有过度活泼,热情,常见的特殊面容有眶周丰满,面颊突出,嘴唇厚,嘴巴宽,人中长,鼻梁扁平。对于语言发育迟缓或构音障碍为主诉的患儿,应注意DiGeorge综合征,DiGeorge综合征除了语言发育迟缓或/和构音障碍以外,还伴有腭咽功能不全,学习障碍,以及小下颌、低耳位和耳廓异常等特殊面容。怀疑William综合征及DiGeorge综合征时需要做MLPA或array-CGH检查,二者分别为7q11.2及22q11.2微缺失。另外,在发育迟缓或矮小的患儿当中,还应注意Cornelia de Lange综合征,该病除了发育迟缓及矮小的表现外,还伴有连眉,弓形眉,睫毛长且弯曲浓密,前额多毛,鼻梁扁平,短鼻、鼻孔前倾,人中长等特殊面容,确诊本病需要做NIPBL基因、SMC1A基因、SMC3基因、RAD21基因及HDAC8基因分析,其中NIPBL基因突变达50%以上。在男性孤独症或智力低下的患儿中,应注意脆性X综合征,该病除了孤独症及智力低下表现,还伴有脸形较长,双耳明显大,前额和下颌突出,嘴大唇厚,高腭弓等特殊面容,确诊需要做FMR-1基因分析。在女性孤独症、发育迟缓或发育倒退的患儿中,应注意Rett综合征,Rett综合征除了有上述表现,还伴有手的刻板动作(绞手、拍手、拍打、咬手、搓手等),确诊需要做MECP2基因分析。在婴幼儿期表现为营养不良、体重不增或发育迟缓以及儿童期表现为肥胖的患儿中,应注意Prader-Willi综合征,Prader-Willi综合征除了上述表现外,还伴有头颅长、窄脸、杏仁眼、小嘴、薄上唇、嘴角向下等典型的特殊面容,该病为父源染色体15q11.2-q13区域印记基因的功能缺陷所致,确诊需要MS-MLPA技术。 展开更多
关键词 William综合征 Cornelia de Lange综合征 脆性X综合征 RETT综合征 DIGEORGE综合征 PRADER-WILLI综合征 发育障碍
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Cornelia de Lange综合症1例报告 被引量:5
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作者 高延 洪琦 《中国儿童保健杂志》 CAS 2011年第7期679-680,共2页
病例:患儿男性,6岁,因"言语及智力发育落后"就诊。至今大小便尚不能自理,只会无意识发"妈妈"音,对指令基本不能理解,在陌生环境里紧张焦虑易哭泣。自幼脾气急躁,多动,哭闹久时唇周青紫,寒冷环境中下肢皮肤出现深浅斑纹。
关键词 Cornelia DE Lange综合症 智力 先天异源性疾病
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A4~12GHz Wideband Balanced MIC Power Amplifier 被引量:1
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作者 姚小江 李滨 +2 位作者 刘新宇 陈中子 陈晓娟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1868-1871,共4页
A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz cente... A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz center frequency with an associated gain of 8.5dB and a gain flatness of + /- 0.6dB in the 4-12GHz frequency range. 展开更多
关键词 WIDEBAND Lange coupler microwave integrated circuit balanced power amplifiers
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具身化的情绪理解研究:James-Lange错了吗? 被引量:20
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作者 张静 陈巍 《心理研究》 2010年第1期46-51,共6页
采用移动窗口技术探讨情绪理解的具身性。以汉语双字形容词为情绪启动材料,通过让被试用"牙齿固定铅笔"和"嘴唇固定铅笔"两种方式控制被试面部表情使其处于"笑"与"无法笑"两种条件下。实验1要... 采用移动窗口技术探讨情绪理解的具身性。以汉语双字形容词为情绪启动材料,通过让被试用"牙齿固定铅笔"和"嘴唇固定铅笔"两种方式控制被试面部表情使其处于"笑"与"无法笑"两种条件下。实验1要求被试在不同的表情条件下对计算机屏幕呈现的词汇进行效价的判断;实验2要求被试在不同的表情条件下对计算机屏幕呈现的词汇进行颜色的判断;实验3要求被试在表情自然条件下对词汇效价进行判断。结果表明,表情控制会影响效价判断、表情控制不会影响颜色判断、词汇效价判断反应时差异不显著。总的实验结果表明,词汇加工能够有效启动情绪,表情控制与词汇加工存在交互作用,说明情绪理解是具身的,即表情控制会影响情绪。 展开更多
关键词 James—Lange 情绪理解 具身认知 模仿 镜像神经元
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