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Spatial distribution modeling of temperature increase for the uplifted mountain terrains and its characteristics in Southwest China 被引量:2
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作者 WANG Yan-xia DING Kun +1 位作者 LI Mao-biao ZHOU Ru-liang 《Journal of Mountain Science》 SCIE CSCD 2017年第11期2270-2283,共14页
Local temperature changes in mountain areas are significantly affected by the uplifted mountain terrains. Understanding how temperature increase with mountain terrains is an important component in accurately modeling ... Local temperature changes in mountain areas are significantly affected by the uplifted mountain terrains. Understanding how temperature increase with mountain terrains is an important component in accurately modeling the spatial distribution of temperature. The study, after minimizing the effect of elevation and latitude, quantitatively simulated the temperature increase in the uplifted mountain terrains, described the characteristics in the spatial distribution of warming areas with different magnitudes, and identified the correlated indices of mountain bodies for warming. Selecting Yunnan Province in southwest China as the study area, we simulated the warming field on a baseline surface at the average elevation of 2000 m and average latitude of 24.96°. The results indicated that the warming magnitudes in different local areas varied with the change in the spatial locations, and the warming process concentrated in the mountainous regions. Throughout the entire study area, the warming field presented a general pattern of three terraces from the regions of high mountains to middle mountains and then low mountains. The areasof high warming magnitude mainly surrounded large mountain bodies and were distributed on the upper part. The areas of low warming magnitude clustered in the valleys and basins of the middle mountain region, mostly on the lower part of the large mountain bodies and its branches. The areas with zero warming magnitude occurred in the low mountains and broad valleys, which were distributed largely on the lower parts of the middle mountains and in most of the valleys. Quantified sampling analysis demonstrated good positive correlation between the warming magnitudes in uplifted mountain terrains and the volume index of the mountain body, as well as elevation difference, with the coefficients corresponding to 0.82 and 0.91, respectively. 展开更多
关键词 uplifted MOUNTAIN terrains Temperature INCREASE BASELINE surface Highwarming MAGNITUDE Remote sensing retrieval
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WHEN THE KUNLUN MTS.PASS AREA UPLIFTED TO PRESENT ELEVATION 被引量:1
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作者 Wu Yongqiu 1,2 , Cui Zhijiu 3, Ge Daokai 3, Liu Gengnian 3 Fax:+86(10)62208178 +1 位作者 E\|mail: yqwu@bnu.edu.cn 2 Key Laboratory of Environmental Change and 《地学前缘》 EI CAS CSCD 2000年第S1期201-202,共2页
Introduction There are big disputes on the uplift of the Tibetan Plateau. Some scientists believe the plateau uplifted to its highest elevation by 14Ma BP,and it decreased in elevation afterward. The second idea about... Introduction There are big disputes on the uplift of the Tibetan Plateau. Some scientists believe the plateau uplifted to its highest elevation by 14Ma BP,and it decreased in elevation afterward. The second idea about the uplift of the plateau was similar to the first one in tectonic theory, but they consider the time of C3 plant change to C4 in the South Asia, as the time when the plateau reached its highest elevation. This time is 8Ma BP. The third idea, the most Chinese scientists believed, the nearest uplift of the plateau took place since 3 4Ma BP. The occurrence of fault depression and gravel deposit with large thickness in the inner and the marge of the plateau represented the speed uplift. After the collision of the India plate and the Eurasia plateau by the 36Ma, the Tibetean area uplifted several times, but it had been planed to lower area. The plateau with 4500m elevation formed in the Quaternary. While our recent research in the Kunlun Pass area suggest , the nearest uplift occurred at the border of the Early and Middle Pleistocene, and before that time, the elevation of this area was no more than 1500 m. 展开更多
关键词 KUNLUN Mts. PASS area UPLIFT PRESENT ELEVATION
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An integrated north–south paleo-Dadu-Anning River: New insights from bulk major and trace element analyses of the Xigeda Formation
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作者 Yong Zheng Hai-bing Li +3 位作者 Jia-wei Pan Ping Wang Ya Lai Zheng Gong 《China Geology》 CAS CSCD 2024年第1期91-103,共13页
The Xianshuihe-Anninghe fault extends SE–S and constitutes the southeastern margin of the Tibetan Plateau.However,the Dadu River which is associated with the fault does not flow following the path,but makes a 90º... The Xianshuihe-Anninghe fault extends SE–S and constitutes the southeastern margin of the Tibetan Plateau.However,the Dadu River which is associated with the fault does not flow following the path,but makes a 90ºturn within a distance of 1 km at Shimian,heading east,and joins the Yangtze River,finally flowing into the East China Sea.Adjacent to the abrupt turn,a low and wide pass near the Daqiao reservoir at Mianning separates the N–S course of the Dadu River from the headwater of the Anning River which then flows south into the Yunnan Province along the Anninghe fault.Therefore,many previous studies assumed southward flow of the paleo-Dadu River from the Shimian to the Anning River.However,evidences for the capture of the integrated N–S paleo-Dadu-Anning River,its timing,and causes are still insufficient.This study explored the paleo-drainage pattern of the Dadu and Anning Rivers based on bulk mineral and geochemical analyses of the large quantities of fluvial/lacustrine sediments along the trunk of the Dadu and Anning Rivers.Similar with sands in the modern Dadu River,the Xigeda sediments also exhibit a granitoid affinity with the bulk major mineral compositions of quartz(>50%),anorthite(about 10%),orthoclase(about 5%),muscovite(about 5%),and clinochlore(about 4%).Correspondingly,bulk major elements show high SiO_(2),with all samples>60%,and some of them>70%,low TiO_(2)(≤0.75%),P_(2)O_(5)(≤0.55%),FeO*(≤5%),and relatively high CaO(1.02%–8.51%),Na_(2)O(1.60%–2.52%),and K_(2)O(2.17%–2.71%),with a uniform REE patterns.Therefore,synthesizing all these results indicate that these lacustrine sediments have similar material sources,which are mainly derived from its course in the Songpan-Ganzi flysch block,implying that the paleo-Dadu originally flowed southward into the Anning River and provided materials to the Xigeda ancient lake.The rearrangement of the paleo-Dadu River appears to be closely related to the locally focused uplift driven by strong activities of the XianshuiheXiaojiang fault system. 展开更多
关键词 Dadu River Anninghe fault River diversion Xigeda Formation Tectonic uplift PROVENANCE Songpan-Ganzi flysch Ancient lake Xianshuihe-Xiaojiang fault system Tibetan Plateau
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AI机器学习:体育消费实验Uplift因果模型研究
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作者 张敖玮 殷亚光 +2 位作者 成瀚宇 唐琳 李星民 《体育科技文献通报》 2024年第4期169-172,共4页
2019年Metalearners for Estimating Heterogeneous Treatment Effects using Machine Learning的发表引发了世界因果推断理论的研究热情。目前,机器学习与因果推断论中的许多统计模型已被广泛应用。本文采用文献资料法、数理统计分析... 2019年Metalearners for Estimating Heterogeneous Treatment Effects using Machine Learning的发表引发了世界因果推断理论的研究热情。目前,机器学习与因果推断论中的许多统计模型已被广泛应用。本文采用文献资料法、数理统计分析方法、案例研究法等研究方法,研究推演现代因果推断理论中较为知名的Uplift因果模型在体育中的应用场景,其中Uplift因果模型包括S-learner(单模型)、T-learner(双模型)、X-learner(交叉训练模型)。结果显示,在体育消费随机对照实验中应用Uplift因果模型,可以基于基本模型进一步推导出各变量因素之间的因果关系,验证并分析自变量对因变量变化的影响;率先在体育消费市场研究与实验中应用Uplift因果模型可以填补我国体育消费实验数据分析方法的空缺。 展开更多
关键词 AI 机器学习 元分析 体育消费 Uplift因果模型
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Determination of minimum overburden depth for underwater shield tunnel in sands:Comparison between circular and rectangular tunnels 被引量:2
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作者 Weixin Sun Fucheng Han +4 位作者 Hanlong Liu Wengang Zhang Yanmei Zhang Weijia Su Songlin Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第7期1671-1686,共16页
With the development of global urbanization,the utilization of underground space is more critical and attractive for civil purposes.Various shapes of shield tunnels have been gradually proposed to cope with different ... With the development of global urbanization,the utilization of underground space is more critical and attractive for civil purposes.Various shapes of shield tunnels have been gradually proposed to cope with different geological conditions and service purposes of underground structures.Generally,reducing the burial depth of shield tunnel is conducive to construction and cost saving.However,extremely small overburden depth cannot provide sufficient uplift resistance to maintain the stability and serviceability of the tunnel.To this end,this paper firstly reviewed the status of deriving the minimum sand over-burden depth of circular shield tunnel using mechanical equilibrium(ME)method.It revealed that the estimated depth is rather conservative.Then,the uplift resistance mechanism of both circular and rectangular tunnels was deduced theoretically and verified with the model tests.The theoretical uplift resistance is consistent with the experimental values,indicating the feasibility of the proposed equations.Furthermore,the determination of the minimum soil overburden depth of rectangular shield tunnel under various working conditions was presented through integrated ME method,which can provide more reasonable estimations of suggested tunnel burial depth for practical construction.Additionally,optimizations were made for calculating the uplift resistance,and the soil thickness providing uplift resistance is suggested to be adjusted according to the testing results.The results can provide reference for the design and construction of various shapes of shield tunnels in urban underground space exploitation. 展开更多
关键词 Minimum overburden depth Uplift resistance mechanism Shield tunnel shape Tunnel anti-floating
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Exploring the rules of cropland elevation uplift in China 被引量:1
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作者 YUAN Jin-tao CHEN Wan-xu +1 位作者 ZENG Jie YE Xin-yue 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1824-1841,共18页
Cropland elevation uplift(CLEU) has recently become a new challenge for agricultural modernization,food security,and sustainable cropland use in China.Uncovering the rules of CLEU is of great theoretical and practical... Cropland elevation uplift(CLEU) has recently become a new challenge for agricultural modernization,food security,and sustainable cropland use in China.Uncovering the rules of CLEU is of great theoretical and practical significance for China’s sustainable agricultural development and rural revitalization strategy.However,existing studies lack in-depth disclosure of multi-scale CLEU evolution rules,making it difficult to support the formulation of specific cropland protection policies.We analyzed the spatio-temporal evolution and multiscale CLEU in China from 1980 to 2020 using the Lorenz curve,gravity center model,hotspot analysis,and cropland elevation spectrum.The results indicated that the center of gravity of cropland moved to the northeast from 1980 to 2000 and then shifted to the northwest.The spatial distribution of cropland became increasingly imbalanced from 1980 to 2000.The change hotspots clustered in the northwest and the northeast,whereas cold-spots were mainly in southeastern China.The average elevation of cropland increased by 17.38 m,and the elevation uplift rule in different regions differed evidently across scales.From 1980 to 2000,all provinces except Xinjiang,Inner Mongolia,Gansu,and Yunnan exhibited CLEU,with Qinghai,Tibet,Beijing,and Guangdong showing the most noticeable uplifting.The CLEU can alleviate the shortage of cropland to some extent.However,without a planning constraint,the CLEU will lead to the increase of ecological risk and food security risk. 展开更多
关键词 CROPLAND Elevation uplift rules MULTI-SCALE Elevation spectrum China
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Texture development of mesophase in reservoir pyrobitumen and the temperature-pressure converting of the gas reservoir in the Chuanzhong Uplift, Southwestern China
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作者 Cheng-Yu Yang Mei-Jun Li +3 位作者 Tie-Guan Wang Ning-Ning Zhong Rong-Hui Fang Long Wen 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期721-732,共12页
The Neoproterozoic-Lower Paleozoic dolostone gas reservoirs in the Chuanzhong Uplift in Southwestern China contain the mesophase pyrobitumen (pyrobitumen with mesophase). The mesophase in the pyrobitumen is mostly com... The Neoproterozoic-Lower Paleozoic dolostone gas reservoirs in the Chuanzhong Uplift in Southwestern China contain the mesophase pyrobitumen (pyrobitumen with mesophase). The mesophase in the pyrobitumen is mostly composed of a mixture of condensed macromolecule polycyclic aromatic hydrocarbons (PAH), and has been mostly converted to various grain, flow, and domain textures. The volcanic activity nearby the Chuanzhong Uplift may have generated very hot (over 300 °C) hydrothermal fluid, with migration of the fluid into the dolostone reservoir transforming the hydrocarbons in the reservoir into an anisotropic carbon by-product, which formed under high temperature and pressure conditions;over 300 °C and 200 MPa according to fluid inclusion analysis. The high temperature-pressure in reservoir was caused by sudden devolatilization of the hydrocarbons due to hydrothermal heating, which formed the unusual texture of the mesophase. The elliptical mesophase grains (EG), the honeycomb structure of pyrobitumen, and the occurrence of polarized classes of mesophase in single pyrobitumen deposits are all unusual textures. This study investigates the texture development of this pressure-affected pyrobitumen. Observation and study of the mesophase suggest that the class of mesophase in pyrobitumen is determined by temperature, while pressure (assessed from associated fluid inclusions) significantly affected the texture. Analysis of the texture of the pyrobitumen in conjunction with previous thermometry results from methane inclusions suggests that the high class mesophase of the pyrobitumen could be applied as a temperature indicator for geological conditions. Furthermore, the unusual textures of the pyrobitumen including elliptical mesophase grains (EG), the honeycomb structure of pyrobitumen, and the occurrence of polarized classes of mesophase in single pyrobitumen could reflect the abnormal high formation pressure. 展开更多
关键词 PYROBITUMEN MESOPHASE Optical texture Pressure affect Oil reservoir Chuanzhong Uplift
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Failure of levees induced by toe uplift:Investigation of post-failure behavior using material point method
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作者 Veronica Girardi Francesca Ceccato +2 位作者 Alex Rohe Paolo Simonini Fabio Gabrieli 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期970-983,共14页
Levees are essential structures in flood defense systems,and their failures can lead to devastating consequences on the surrounding territories.One of the failure mechanisms mostly controlled by the foundation soil st... Levees are essential structures in flood defense systems,and their failures can lead to devastating consequences on the surrounding territories.One of the failure mechanisms mostly controlled by the foundation soil stratigraphy is the instability of the land side slope,triggered by the development of high uplift pressures in the foundation.This complex phenomenon has been investigated experimentally with centrifuge tests or large-scale tests and numerically with the limit equilibrium method(LEM)and the finite element method(FEM).In this work,we applied a multiphase formulation of the material point method(MPM)to analyze the development of toe uplift instability mechanism,from the onset of failure to large displacements.The numerical model is inspired by an experiment carried out in a geotechnical centrifuge test by Allersma and Rohe(2003).The comparison with the experiment allows for understanding critical pore pressure triggering large displacements in the foundation soils.Moreover,we numerically evaluated the impact of different values of foundation soils’hydraulic conductivity on the failure mechanism.The results show that hydraulic conductivity mainly influences the time of failure onset and the extension of shear localization at depth.Finally,the advantages of using large displacement approaches in the safety assessment of earth structures are discussed.Unlike FEM,there are no issues with element distortions generating difficulties with numerical convergence,allowing for full postfailure reproduction.This capability permits precise quantification of earth structure damages and post-failure displacements.The ensuing reinforcement systems’design is no longer over-conservative,with a significant reduction in associated costs. 展开更多
关键词 Slopes safety assessment LEVEES Uplift pressure Large deformation analysis
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Investigation of groundwater characteristics and its influence on Landslides in Heifangtai Plateau using comprehensive geophysical methods
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作者 Feng-dan Yu Gang Qiao +1 位作者 Kai Wang Xu Zhang 《Journal of Groundwater Science and Engineering》 2023年第2期171-182,共12页
The occurrence of landslides in Heifangtai plateau is primarily caused by the rise in water levels due to irrigation. To accurately understand the distribution of groundwater and its impact on the landslide hazard, a ... The occurrence of landslides in Heifangtai plateau is primarily caused by the rise in water levels due to irrigation. To accurately understand the distribution of groundwater and its impact on the landslide hazard, a combination of Electrical Resistivity Tomography(ERT), Induced Polarization(IP) and Surface Nuclear Magnetic Resonance(SNMR) methods were used in this study. By conducting a comprehensive analysis, the characteristics of water-bearing structure in vertical and groundwater distribution in horizontal were detected;and the influence of the groundwater on plateau and landslides was also identified. The results indicate that the groundwater occurs in the loess aquifer with a three-layer structure in vertical.Horizontally, the aquifer has a unified water table over the plateau, with a low water level in the north and high one in the south. The high resistivity bedrock uplift belt in the middle of the plateau forms a watershed,with the north side of the uplift belt being a relatively stable slope area with stable water content and fewer geological disasters. In contrast, the south side of the uplift belt is a disaster-prone region with vertical fissures well developed in the loess aquifers. The southern landslides are characterized by the interphase distribution of high and low electrical resistivity. The infiltration and discharge of groundwater result in the formation of a collapse belt in the low resistivity water-bearing structure of landslide, which causes the entire block with high resistivity and stable bedrock to slide. There was a newly formed landslide in a larger range at the landslide' s trailing edge. This study provides a scientific basis for the study of landslides mechanisms and disaster prevention by identifying the distribution characteristics of groundwater and analyzing its influence from a geophysical perspective in Heifangtai. 展开更多
关键词 ERT IP SNMR Distribution characteristics Uplift belt Sliding surface
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Geochemical characteristics of Sr isotopes in the LS33 drill core from the Qiongdongnan Basin, South China Sea, and their response to the uplift of the Tibetan Plateau
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作者 Ke Wang Shikui Zhai +1 位作者 Zenghui Yu Huaijing Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第5期117-129,共13页
Making full use of modern analytical and testing techniques to explore and establish new indexes or methods for extracting paleoseawater geochemical information from sediments will help to reconstruct the sedimentary ... Making full use of modern analytical and testing techniques to explore and establish new indexes or methods for extracting paleoseawater geochemical information from sediments will help to reconstruct the sedimentary paleoenvironment in different research areas.The connection between the subsidence of the South China Sea basin and the uplift of the Tibetan Plateau has been a scientific concern in recent decades.To explore the information on the sedimentary paleoenvironment,provenance changes and uplift of Tibetan Plateau contained in core sediments(debris),we selected core samples from Well LS33 in the Qiongdongnan Basin,South China Sea,and analyzed the contents of typical elements(Al,Th,and rare earth elements)that can indicate changes in provenance and the Sr isotopic compositions,which can reveal the geochemical characteristics of the paleoseawater depending on the type of material(authigenic carbonate and terrigenous detritus).The results show the following:(1)during the late Miocene,the Red River transported a large amount of detrital sediments from the ancient continental block(South China)to the Qiongdongnan Basin.(2)The authigenic carbonates accurately record changes in the 87Sr/86Sr ratios in the South China Sea since the Oligocene.These ratios reflect the semi-closed marginal sea environment of the South China Sea(relative to the ocean)and the sedimentary paleoenvironment evolution process of the deep-water area of the Qiongdongnan Basin from continental to transitional and then to bathyal.(3)Since the Neogene,the variations in the 87Sr/86Sr ratio in the authigenic carbonates have been consistent with the variations in the uplift rate of the Tibetan Plateau and the sediment accumulation rate in the Qiongdongnan Basin.These consistent changes indicate the complex geological process of the change in the rock weathering intensity and terrigenous Sr flux caused by changes in the uplift rate of the Tibetan Plateau,which influence the Sr isotope composition of seawater. 展开更多
关键词 sediments from a drill core grouping analysis elements and Sr isotopes provenance and paleoenvironment uplift of the Tibetan Plateau and subsidence of the South China Sea basin
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Night Vision Object Tracking System Using Correlation Aware LSTM-Based Modified Yolo Algorithm
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作者 R.Anandha Murugan B.Sathyabama 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期353-368,共16页
Improved picture quality is critical to the effectiveness of object recog-nition and tracking.The consistency of those photos is impacted by night-video systems because the contrast between high-profile items and diffe... Improved picture quality is critical to the effectiveness of object recog-nition and tracking.The consistency of those photos is impacted by night-video systems because the contrast between high-profile items and different atmospheric conditions,such as mist,fog,dust etc.The pictures then shift in intensity,colour,polarity and consistency.A general challenge for computer vision analyses lies in the horrid appearance of night images in arbitrary illumination and ambient envir-onments.In recent years,target recognition techniques focused on deep learning and machine learning have become standard algorithms for object detection with the exponential growth of computer performance capabilities.However,the iden-tification of objects in the night world also poses further problems because of the distorted backdrop and dim light.The Correlation aware LSTM based YOLO(You Look Only Once)classifier method for exact object recognition and deter-mining its properties under night vision was a major inspiration for this work.In order to create virtual target sets similar to daily environments,we employ night images as inputs;and to obtain high enhanced image using histogram based enhancement and iterative wienerfilter for removing the noise in the image.The process of the feature extraction and feature selection was done for electing the potential features using the Adaptive internal linear embedding(AILE)and uplift linear discriminant analysis(ULDA).The region of interest mask can be segmen-ted using the Recurrent-Phase Level set Segmentation.Finally,we use deep con-volution feature fusion and region of interest pooling to integrate the presently extremely sophisticated quicker Long short term memory based(LSTM)with YOLO method for object tracking system.A range of experimentalfindings demonstrate that our technique achieves high average accuracy with a precision of 99.7%for object detection of SSAN datasets that is considerably more than that of the other standard object detection mechanism.Our approach may therefore satisfy the true demands of night scene target detection applications.We very much believe that our method will help future research. 展开更多
关键词 Object monitoring night vision image SSAN dataset adaptive internal linear embedding uplift linear discriminant analysis recurrent-phase level set segmentation correlation aware LSTM based yolo classifier algorithm
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An Orthogonal Collision Dynamic Mechanism of Wave-Like Uplift Plateaus in Southern Asia
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作者 Weihong Qian Jeremy Cheuk-Hin Leung Banglin Zhang 《Open Journal of Geology》 2023年第8期828-846,共19页
In southern Asia, there are three large-scale wave-like mountains ranging from the Tibetan Plateau westward to the Iranian Plateau and the Armenian Plateau. On the southern side between plateaus, there are the Indian ... In southern Asia, there are three large-scale wave-like mountains ranging from the Tibetan Plateau westward to the Iranian Plateau and the Armenian Plateau. On the southern side between plateaus, there are the Indian Peninsula and the Arabian Peninsula. What dynamic mechanisms form the directional alignment of the three plateaus with the two peninsulas remains a mystery. In the early stages of the Earth’s geological evolution, the internal structure of the Earth was that the center was a solid core, and the outmost layer was a thin equatorial crust zone separated by two thick pristine continents in polar areas, while the middle part was a deep magma fluid layer. Within the magma fluid layer, thermal and dynamic differences triggered planetary-scale vertical magma cells and led to the core-magma angular momentum exchange. When the core loses angular momentum and the magma layer gains angular momentum, the movement of upper magma fluids to the east and the tropical convergence zone (TCZ) drives the split and drift of two thick pristine continents, eventually forming the current combination of these plateaus and peninsulas and their wave-like arrangement along the east-west direction. Among them, the horizontal orthogonal convergence (collision) of upper magma fluids from the two hemispheres excited the vertical shear stress along the magma TCZ, which is the dynamic mechanism of mountain uplifts on the north side and plate subductions on the south side. To confirm this mechanism, two examples of low-level winds are used to calculate the correspondence between cyclone/anticyclonic systems generated by the orthogonal collision of airflows along the atmospheric TCZ and satellite-observed cloud systems. Such comparison can help us revisit the geological history of continental drift and orogeny. 展开更多
关键词 Plateau Uplift Plate Subduction Tibetan Plateau Iranian Plateau Armenian Plateau
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Soft Sediment Deformation Structures in the Sediment Deposits of Ganga River and Its Oxbow Lakes in Parts of Indo-Gangetic Plain: Implications for Quake Proxies and Paleoseismicity Tracking
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作者 Gufran Ali Mohd Sajid Mohammad Shamim Khan 《International Journal of Geosciences》 CAS 2023年第1期75-93,共19页
The Late Quaternary thick sedimentary fills of the Ganga basin predominantly consist of unconsolidated fluvial sandy deposits which are often intercalated with mud. These deposits at various places record the evidence... The Late Quaternary thick sedimentary fills of the Ganga basin predominantly consist of unconsolidated fluvial sandy deposits which are often intercalated with mud. These deposits at various places record the evidence of earthquakes, which occurred in the recent geological past. The evidence is contained and manifested in the form of Soft Sediment Deformation Structures (SSDSs). Saturated sediments/muds/soils are liquefied by earthquake tremors which either generate SSDS or produce structural discordance in the pre-existing sedimentary structures. The present study reports the occurrence of SSDS, e.g. load and associated flame structures, clastic dikes and sill structures, slump structures and sedimentary breccias, etc. from the Ganga River and adjacent oxbow lake sediment deposits. An attempt has been made to establish the origin of soft sediment structures of this region in accordance with its neotectonic history and in turn, identification of seismic structural proxies to delineate paleoseismic events in this region with futuristic implications. The preservation of soft sediment deformation structures in large numbers with multiple geomorphology and scale, in the river and adjoining lake sediments, is indicative of frequent earthquakes of high magnitude consequent to tectonic activism in the Himalayan region. 展开更多
关键词 Quaternary Sediments Flood Plain Central Ganga Basin Sediment Dynamism Himalayan Uplift Paleoquakes
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噻托溴铵治疗稳定期慢性阻塞性肺疾病的疗效评价 被引量:16
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作者 冯玉麟 邱婷 唐永江 《世界临床药物》 CAS 2009年第1期15-19,26,共6页
噻托溴铵是新一代治疗慢性阻塞性肺疾病(COPD)的吸入型长效抗胆碱药物,通过选择性作用于M1和M3受体,扩张支气管,疗效持续,每天只需使用一次。UPLIFT研究结果进一步证实,长期规律使用噻托溴铵能够改善中重度、极重度稳定期COPD患者肺功... 噻托溴铵是新一代治疗慢性阻塞性肺疾病(COPD)的吸入型长效抗胆碱药物,通过选择性作用于M1和M3受体,扩张支气管,疗效持续,每天只需使用一次。UPLIFT研究结果进一步证实,长期规律使用噻托溴铵能够改善中重度、极重度稳定期COPD患者肺功能情况,缓解症状、提高运动耐量及改善生活质量,延长急性发作的时间间隔、减少急性加重发作次数,降低COPD患者死亡率,具有良好的安全性。 展开更多
关键词 噻托溴铵 抗胆碱药物 吸入制剂 慢性阻塞性肺疾病 UPLIFT研究
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Tibet,the Himalaya,Asian monsoons and biodiversity-In what ways are they related? 被引量:31
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作者 Robert A. Spicer 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第5期233-244,共12页
Prevailing dogma asserts that the uplift of Tibet, the onset of the Asian monsoon system and high biodiversity in southern Asia are linked, and that all occurred after 23 million years ago in the Neogene.Here, spannin... Prevailing dogma asserts that the uplift of Tibet, the onset of the Asian monsoon system and high biodiversity in southern Asia are linked, and that all occurred after 23 million years ago in the Neogene.Here, spanning the last 60 million years of Earth history, the geological, climatological and palaeontological evidence for this linkage is reviewed. The principal conclusions are that: 1) A proto-Tibetan highland existed well before the Neogene and that an Andean type topography with surface elevations of at least 4.5 km existed at the start of the Eocene, before final closure of the Tethys Ocean that separated India from Eurasia. 2) The Himalaya were formed not at the start of the India-Eurasia collision, but after much of Tibet had achieved its present elevation. The Himalaya built against a pre-existing proto-Tibetan highland and only projected above the average height of the plateau after approximately 15 Ma. 3)Monsoon climates have existed across southern Asia for the whole of the Cenozoic, and probably for a lot longer, but that they were of the kind generated by seasonal migrations of the Inter-tropical Convergence Zone. 4) The projection of the High Himalaya above the Tibetan Plateau at about 15 Ma coincides with the development of the modern South Asia Monsoon. 5) The East Asia monsoon became established in its present form about the same time as a consequence of topographic changes in northern Tibet and elsewhere in Asia, the loss of moisture sources in the Asian interior and the development of a strong winter Siberian high as global temperatures declined. 6) New radiometric dates of palaeontological finds point to southern Asia's high biodiversity originating in the Paleogene, not the Neogene. 展开更多
关键词 Tibetan Plateau HIMALAYA Uplift history MONSOONS BIODIVERSITY Molecular phylogeny
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The Uplift of the Longmenshan Thrust Belt and Subsidence of the West Sichuan Foreland Basin 被引量:21
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作者 Liu Shugen, Luo Zhili, Dai Sulan, Changlu Institute of Technology, Chengdu, Sichuan, ChinaDennis Arne Dalhousie U niversity, Canadaand C.J.L. Wilson Melbourne U niversity, Australia Jiang M inxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1996年第1期16-26,共11页
Based on fission track dating of apatite, and measurement of vitrinite reflectance of rock samples from the Longmenshan (Longmen Mountain)area and the West Sichuan foreland basin and computer modelling it is concluded... Based on fission track dating of apatite, and measurement of vitrinite reflectance of rock samples from the Longmenshan (Longmen Mountain)area and the West Sichuan foreland basin and computer modelling it is concluded that (l)the Songpan-Garze fold belt has uplifted at least by 3-4 km with an uplift rate of no less than 0.3-0.4 mm/a since 10 Ma B.P.; (2) the Longmenshan thrust nappe belt has uplifted at least by 5-6 km with an uplift rate of more than 0.5- 0.6 mm /a since 10 Ma B.P.; (3) the Longmenshan detachment belt has uplifted by 1 - 2 km at a rate of 0.016-0.032 mm/a since 60 Ma B.P.; (4) the West Sichuan foreland basin has uplifted by 1.7-3 km at a rate of 0.028-0.05 mm/a since 60 Ma B.P.; (5) the uplift rate of the area on the west side of the Beichuan-Yingxiu-Xiaoguanzi fault for the last 10 Ma is 40 times as much as that on its east side; (6) the uplifting of the the Songpan - Garze fold belt and the subsidence of the West Sichuan foreland basin 60 Ma ago exhibit a mirro-image correlation, i. 展开更多
关键词 fission track uplift (subsidence) history BASIN modelling LONGMENSHAN thrust belt West SICHUAN FORELAND BASIN
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Sedimentary Record of the Planation Surface in the Hoh Xil Region of the Northern Tibet Plateau 被引量:22
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作者 YI Haisheng WANG Chengshan +2 位作者 LIU Shun LIU Zhifei WANG Shifeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第4期827-835,共9页
Miocene marl is the most widespread Tertiary stratigraphic record in the northern Tibet Plateau, termed the Wudaoliang Group in the Hoh Xil region and the correlative Suonahu Formation in the Qiangtang region. The uni... Miocene marl is the most widespread Tertiary stratigraphic record in the northern Tibet Plateau, termed the Wudaoliang Group in the Hoh Xil region and the correlative Suonahu Formation in the Qiangtang region. The uniform marl overlies red beds of the Eocene-Oligocene Fenghuoshan Group. The Wudaoliang Group is generally 100-400 m thick, but the thickest strata are 700-1300 m, located in the Haidinghu (Maiding Lake) and Tuotuohe (Tuotuo River) regions respectively. Based on observations from eight measured sections and outcrops, the thin-bedded marl, which varies in colour from grey-white to light brown-grey, is explained as a large-scale or serial lacustrine deposit stretching throughout northern Tibet.The Wudaoliang Group commonly crops out on geographic lowland at an average elevation of 4600 m above sea level within the mountain chains, showing concordant summit levels, e.g. the Fenghuoshan and Bairizhajia Mountains. These mountains with a flat ridge are considered to be remains of the 展开更多
关键词 MIOCENE sedimentary record planation surface UPLIFT COLLAPSE Hoh Xil northern Tibet
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Distribution and Significance of Carbazole Compounds in Palaeozoic Oils from the Tazhong Uplift, Tarim 被引量:11
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作者 LIU Luofu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1998年第1期87-93,共7页
Carbazole compounds in crude oils from the Tazhong uplift of the Tarim basin have been fractionated and detected and successfully used to study petroleum migration and trace source rocks in the study area. Alkylcarbaz... Carbazole compounds in crude oils from the Tazhong uplift of the Tarim basin have been fractionated and detected and successfully used to study petroleum migration and trace source rocks in the study area. Alkylcarbazoles have been found in large amounts in the oil samples analyzed and alkylbenzocarbazoles detected in a small concentration only in part of the samples, but alkyldibenzocarbazoles have not been found in oils. Based on the distribution of G1, G2 and G3 of C2-alkylcarbazoles, the ratio of C3-carbazoles to C2-carbazoles and the relative amounts of alkylcarbazoles and alkylbenzocarbazoles, one can know that the vertical oil migration in the Tazhong uplift is generally from below upward, i.e. from the Ordovician through the Silurian to the Carboniferous. Evidently, source rocks in the uplift should be lower Palaeozoic strata (Ordovician and Cambrian). This study shows that carbazoles are of great importance in the study of petroleum migration and source rocks. 展开更多
关键词 Tarim basin Tazhong uplift pyrrolic nitrogen compounds oil migration oil source
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Garnet-bearing Granulite Facies Rock Xenoliths from Late Mesozoic Volcaniclastic Breccia, Xinyang, Henan Province 被引量:7
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作者 ZHENG Jianping, SUN Min, LU Fengxiang, WANG Chunyangand ZHONG Zengqiu Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China Department of Earth Sciences, The University of Hong Kong, China 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第4期445-451,共7页
This paper presents the primary results of petrologic,mineralogical and petrochemical studies of garnet beating granulite facies rock xenoliths from Xinyang, Henan Province. These xenoliths, which are found in a pipe ... This paper presents the primary results of petrologic,mineralogical and petrochemical studies of garnet beating granulite facies rock xenoliths from Xinyang, Henan Province. These xenoliths, which are found in a pipe of late Mesozoic volcaniclastic breccia, are of high density (3.13-3.30 g/cm3) and high seismic velocity (Vp = 7.04-7.31 km/s), being products of underplating of basaltic magmas and had experienced granulite facies metamorphism. The underplating and metamorphism took place before the eruption of the host rock. Petrographical studies and equilibrium T-P calculations show that these xenoliths were captured at a 49 km depth and experienced at least a 16 km uplift before they were captured. The dynamics of the uplift could be related to the continent-continent collision between the North China plate and the Yangtze plate during the Triassic. 展开更多
关键词 granulite facies mafic rock XENOLITH uplift Xinyang
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Upward surface movement above deep coal mines after closure and flooding of underground workings 被引量:6
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作者 André Vervoort Pierre-Yves Declercq 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第1期53-59,共7页
After the mass closures of entire coal mine districts in Europe at the end of the last century, a new phenomenon of surface movement was observed—an upward movement.Although most surface movement(i.e., subsidence) oc... After the mass closures of entire coal mine districts in Europe at the end of the last century, a new phenomenon of surface movement was observed—an upward movement.Although most surface movement(i.e., subsidence) occurs in the months and years after mining by the longwall method, surface movement still occurs many decades after mining is terminated.After the closure and flooding of underground excavations and surrounding rock, this movement was reversed.This paper focuses on quantifying the upward movement in two neighboring coal mines(Winterslag and Zwartberg, Belgium).The study is based on data from a remote sensing technique: interferometry with synthetic aperture radar(INSAR).The results of the study show that the rate of upward movement in the decade after closure is about 10 mm/year on average.The upward movements are not linked directly to the past exploitation directly underneath a location.The amounts of subsidence at specific locations are linked mainly to their positions relative to an inverse trough shape situated over the entire mined-out areas and their immediate surroundings.Local features, such as geological faults, can have a secondary effect on the local variation of the uplift.The processes of subsidence and uplift are based on completely different mechanisms.Subsidence is initiated by a caving process, while the process of uplift is clearly linked to flooding. 展开更多
关键词 Coal mining Surface movement SUBSIDENCE UPLIFT Radar-interferometry
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