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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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Tectonic Affinity, T-t Path and Uplift Trajectory of Eclo gites from Northern Dabie Mountains, Central-Eastern China 被引量:3
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作者 LiuYican XuShutong +3 位作者 LiShuguang JiaagLaili ChenGuanbao WuWeiping 《Journal of China University of Geosciences》 SCIE CSCD 2003年第1期28-33,共6页
Petrologic geochemistry and isotopic chronology of the eclogites sug ge st that most of the eclogites in northern Dabie Mountains produced from the Tria ssic Yangtze subducted continental crust (lower crust and formed... Petrologic geochemistry and isotopic chronology of the eclogites sug ge st that most of the eclogites in northern Dabie Mountains produced from the Tria ssic Yangtze subducted continental crust (lower crust and formed during the deep subduction) and the metamorphosed mafic untramafic belt with eclogite, marble and meta peridotite blocks around the Mozitan Xiaotian fault zone may represen t the meta tectonic melange produced during the active subduction of an ancient oceanic slab and subsequent collision between the Yangtze and North China conti nental plates. The cooling history of the eclogites from ~900 ℃ to 300 ℃ can b e subdivided into three stages: one isothermal stage and two rapid cooling stage s. The initial stage between (230±6) and 210 Ma was a near isothermal or tempe rature rise process corresponding to the retrograded metamorphism of granulite facies with a rapid uplift of 4 mm/a, then two fast cooling stages occurred with cooling rate of ~10 ℃/Ma during 210 Ma to (172±3) Ma and ~4 ℃/Ma durin g (172±3) Ma to 130 Ma. After the peak metamorphism of eclogite facies, their in itial isothermal stage with slower uplift rate and cooling rate and high T overprinting of granulite facies metamorphism is the major difference between t he eclogites in northern Dabie Mountains from those in southern Dabie Mountains. This may be one of the most important reasons to preserve few evidences of earl ier ultrahigh pressure metamorphism. 展开更多
关键词 ECLOGITE tectonic affinity T t path and uplift trajectory nor thern Dabie mountains.
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Crustal Uplift in the Longmen Shan Mountains Revealed by Isostatic Gravity Anomalies along the Eastern Margin of the Tibetan Plateau 被引量:3
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作者 LI Yong YAN Zhaokun +4 位作者 ZHOU Rongjun YAN Liang DONG Shunli SHAO Chongjian Svirchev LAURENCE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第1期56-73,共18页
This study examines the relationship between high positive isostatic gravity anomalies (IGA), steep topography and lower crustal extrusion at the eastern margin of the Tibetan Plateau. IGA data has revealed uplift a... This study examines the relationship between high positive isostatic gravity anomalies (IGA), steep topography and lower crustal extrusion at the eastern margin of the Tibetan Plateau. IGA data has revealed uplift and extrusion of lower crustal flow in the Longmen Shan Mountains (the LMS). Firstly, The high positive IGA zone corresponds to the LMS orogenic belt. It is shown that abrupt changes in IGA correspond to zones of abrupt change of topography, crustal thickness and rock density along the LMS. Secondly, on the basis of the Airy isostasy theory, simulations and inversions of the positive IGA were conducted using three-dimensional bodies. The results indicated that the LMS lacks a mountain root, and that the top surface of the lower crust has been elevated by 11 km, leading to positive IGA, tectonic load and density load. Thirdly, according to Watts's flexural isostasy model, elastic deflection occurs, suggesting that the limited (i.e. narrow) tectonic and density load driven by lower crustal flow in the LMS have led to asymmetric flexural subsidence in the foreland basin and lifting of the forebulge. Finally, based on the correspondence between zones of extremely high positive IGA and the presence of the Precambrian Pengguan-Baoxing complexes in the LMS, the first appearance of erosion gravels from the complexes in the Dayi Conglomerate layer of the Chengdu Basin suggest that positive IGA and lower crustal flow in the LMS took place at 3.6 Ma or slightly earlier. 展开更多
关键词 isostatic gravity anomalies crustal uplift Longmen shan mountains lower crustal flow foreland basin the eastern margin of the Tibetan Plateau
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The influence factors of gas-bearing and geological characteristics of Niutitang Formation shale in the southern margin of Xuefeng Mountain ancient uplift: A case of Well Huangdi 1 被引量:6
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作者 Ming-na Ge Ke Chen +2 位作者 Xiang-lin Chen Chao Wang Shu-jing Bao 《China Geology》 2020年第4期533-544,共12页
In order to evaluate the geological characteristics and gas-bearing factors of Niutitang Formation within the Lower Cambrian of northern Guizhou,the Huangping area located at the southern edge of the ancient uplift be... In order to evaluate the geological characteristics and gas-bearing factors of Niutitang Formation within the Lower Cambrian of northern Guizhou,the Huangping area located at the southern edge of the ancient uplift belt of Xuefeng Mountain was selected as the target area,and Well Huangdi 1 was drilled for the geological survey of shale gas.Through geological background analysis and well logging and laboratory analysis such as organic geochemical test,gas content analysis,isothermal adsorption,and specific surface area experiments on Well Huangdi 1,the results show that the Niutitang Formation is a deep-water shelf,trough-like folds and thrust fault.The thickness of black shale is 119.95 m,of which carbonaceous shale is 89.6 m.The average value of organic carbon content is 3.55%,kerogen vitrinite reflectance value is 2.37% and kerogen type is sapropel-type.The brittle mineral content is 51%(quartz 38%),clay mineral content is 38.3%.The value of porosity and permeability are 0.5%and 0.0014 mD,which the reservoir of the Niutitang Formation belongs to low permeability with characteristics of ultra-low porosity.The gas content is 0.09‒1.31 m^3/t with a high-value area and a second high-value area.By comparing with the geological parameters of adjacent wells in the adjacent area,the accumulation model of“sediment control zone,Ro control zone,structure controlling reservoir”in the study area is proposed.Therefore,deep-water shelf-slope facies,Ro is between high maturity-early stage of overmaturity and well-preserved zones in the Niutitang Formation in this area are favorable direction for the next step of shale gas exploration. 展开更多
关键词 shale gas Gas-bearing Well Huangdi 1 Influence factors Niutitang Formation Xuefeng mountain ancient uplift Oil and gas exploration engineering Lower Cambrian Guizhou Province China
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Late Cenozoic Tectonic Uplift Producing Mountain Building in Comparison with Mantle Structure in the Alpine-Himalayan Belt 被引量:1
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作者 Vladimir G. Trifonov Sergey Yu. Sokolov 《International Journal of Geosciences》 2014年第5期497-518,共22页
Tectonic uplift producing recent mountain systems has spanned in the Alpine-Himalayan Belt the time interval from Oligocene to Recent (the last 30 - 35 Ma), being divided into two stages. During the first stage, local... Tectonic uplift producing recent mountain systems has spanned in the Alpine-Himalayan Belt the time interval from Oligocene to Recent (the last 30 - 35 Ma), being divided into two stages. During the first stage, local uplands, usually not higher than middle-elevated mountains, rose and their total area increased. During the second stage (the last 5 - 2 Ma) this process was accompanied by a total uplift of the greater part of the belt. As a result, the rate of vertical movements increased, the recent mountain systems were formed, and the coarse molasses accumulated in the adjacent basins. Uplift of the land surface resulting in formation of mountain topography is an isostatic reaction to decompaction of the upper spheres of the Solid Earth. Three factors of the decompaction are discussed in the paper. These are: I, collisional compression, resulting in deformational thickening of the Earth’s crust (folding, thrusting, etc.);II, partial replacing of the lithosphere mantle by the lower-dense asthenosphere material and, as a result, decompaction of the uppermost mantle;and III, retrograde metamorphism of high-metamorphosed rocks within the lower crust and near the crust-mantle boundary and, as a result, decompaction of these rocks. These processes were initiated or facilitated by the lateral asthenosphere flows. According to the seismic tomography data, the flows spread from the stationary developed zone of the rise of deep mantle material that is expressed in the recent structure as the Ethiopian-Afar super-plume. Reworking the 400 - 700-km deep transition layer of the mantle, the sub-lithosphere flows could be enriched in sources of aqueous fluids. The flows and their fluids initiated factors II and III of the tectonic uplift and caused softening and detachment of the lithosphere, facilitating deformational thickening of the Earth’s crust, i.e., the factor I. The latter produced uplands during the entire Oligocene-Quaternary development of the orogenic belt, while the factors II and III manifested themselves only during the second stage of mountain building. The detailed studies in the Central Tien Shan and the Greater Caucasus showed that the acceleration of uplift at the second stage was caused mainly by the factor II in the Central Tien Shan and the factor III in the Greater Caucasus. 展开更多
关键词 Late CENOZOIC uplift mountain Building seismic Tomography Profiles LITHOsPHERE AsTHENOsPHERE
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Episodic Orogeny Deduced from Coeval Sedimentary Sequences in the Foreland Basin and Its Implication for Uplift Process of Longmen Mountain,China 被引量:3
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作者 LI Yong SU De-chen +4 位作者 ZHOU Rong-jun LI Hai-bing Alexander L.DENSMORE YAN Liang YAN Zhao-kun 《Journal of Mountain Science》 SCIE CSCD 2013年第1期29-42,共14页
Longmen Mountain located at the boundary between the Sichuan Basin and Tibetan Plateau,representing the steepest gradient of any edges of the plateau.Three endmember models of uplift process and mechanism have been pr... Longmen Mountain located at the boundary between the Sichuan Basin and Tibetan Plateau,representing the steepest gradient of any edges of the plateau.Three endmember models of uplift process and mechanism have been proposed,including crustal thickening,crustal flow,and crustal isostatic rebound.Here we use coeval sedimentary sequences in the foreland basin to restraint uplift process and mechanism in the Longmen Mountain.The more than 10,000 m thick Late TriassicQuaternary strata filled in this foreland basin and can be divided into six megasequences that are distinguished as two distinct types.The first type is the wedge-shaped megasequences which are sedimentary response of strong active thrust loading events,characterized by a high rate of subsidence and sediment accumulation,coarsening-upward succession and a dual-sourced sediment supply.This type includes Late Triassic,Late Jurassic to Early Cretaceous and Late Cretaceous to Paleogene megasequences.The second type is the tabular megasequences,characterized by the low rate of subsidence and sediment accumulation,finingupward succession,and a single-sourced sediment supply,which is sedimentary response of isostatic rebound and erosion unloading.This type includes the Early to Middle Jurassic,Middle Cretaceous and Neogene to Quaternary megasequences.Basing on sedimentary,active tectonic,geomorphic evidence,we infer that the direction has been reversed from SSWdirected sinistral strike-slip to NNE-directed dextral strike-slip during 40-3.6 Ma,and since 3.6 Ma,the Longmen Mountain thrust belt belong to times of isostatic rebound and erosional unloading with NNEdirected dextral strike-slip.This suggests that crustal isostatic rebound is a primary driver for uplift and topography of the present Longmen Mountain.The Wenchuan(Ms8.0) earthquake,which ruptured a large thrust fault with NNE-directed dextral strikeslip along the range front,is an active manifestation of this crustal isostatic rebound process with dextral strike-slipping and shortening.This process may be the cause for the Wenchuan Earthquake and the apparent paradox of high relief,little shortening,the relative dearth of historical seismicity in the region. 展开更多
关键词 Wedge-shaped megasequence Tabular megasequence Orogenic loading Erosional unloading uplift process Longmen mountain Foreland basin
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Cosmogenic ^(26)Al/^(10)Be Burial Dating of the Uplift Rate of Southern Qinling Mountains since the Middle Pleistocene 被引量:1
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作者 LU Yiming SUN Xuefeng +2 位作者 TU Hua ZENG Qiongxuan XU Xinghua 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第4期1674-1675,共2页
Objective The Qinling Mountains (QM) in Central China is a natural harrier that corresponds to the boundary between the southern and northern climate and environment (Gong Hujun et al., 2017). Northern QM is rela... Objective The Qinling Mountains (QM) in Central China is a natural harrier that corresponds to the boundary between the southern and northern climate and environment (Gong Hujun et al., 2017). Northern QM is relatively steep, and southern QM is in contrast relatively low and gentle. Investigations have shown that the average uplift rate of northern QM since 17.8 Ma is approximately 0.19 mm/a (Yin Gongming et al., 2001), whereas that of central QM since 0.36 Ma is approximately 0.32 mm/a (Wang Fei et al., 2004). To date, however, few investigations have yet been conducted on the uplift rate of southern QM. Accordingly, we aim to obtain the uplift rate of southern QM by using the cosmogenic ^26A1/^10 Be burial dating method to determine the age of the highest river terrace on the southern slope of QM. 展开更多
关键词 Be Burial Dating of the uplift Rate of southern Qinling mountains since the Middle Pleistocene COsMOGENIC QM Al
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THREE-DIMENSIONAL DEFORMATION ALONG THE ALTYN TAGH FAULT ZONE AND UPLIFT OF THE ALTYN MOUNTAIN, NORTHERN TIBET
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作者 Li Haibing, Yang Jingsui, Xu Zhiqin, Zhang Jianxin, Wu Cailai,Shi Rendeng (Institute of Geology, Chinese Academy of Geological Sciences, 26 Baiwanzhuang Road, Beijing 100037, China,E\|mail: lihaibing@yeah.net yangjsui@public.bta.net.cn) 《地学前缘》 EI CAS CSCD 2000年第S1期257-258,共2页
he convergence between India and Eurasia is partly accommodated by motion of a few large blocks along strike\|slip faults. About 1800km long Altyn Tagh fault strikes in N60~80°E and allows the northeastward disp... he convergence between India and Eurasia is partly accommodated by motion of a few large blocks along strike\|slip faults. About 1800km long Altyn Tagh fault strikes in N60~80°E and allows the northeastward displacement of the Tibet plateau relative to the Tarim. The Altyn Tagh fault zone is a typical transpressional fault zone, characterized by blocks rotation and crustal shortening and vertical extrusion of blocks within the Altyn Tagh strike\|slip system. Differences of three\|dimensional deformation and configuration of the active structures are recognized at different segment of the Altyn Tagh fault zone.1\ Structural configuration of the Altyn Tagh fault zone\;In the Altyn Tagh strike\|slip fault zone, the assemblage pattern of the (active) faults is in the form of parallel plumes, especially in the eastern and the western segments of the Altyn Tagh fault zone. These plumes structures in the eastern segment are assembled by string\|like left lateral strike\|slip fault and broom\|like thrusting faults, and in the western segment by arc\|like left lateral strike\|slip faults along with thrusting faults and normal faults. In the middle segment of the Altyn Tagh fault zone, the structures are characterized by the string\|like left lateral strike\|slip faults in the center and reverse thrusting faults on the two sides. 展开更多
关键词 three\|dimensional DEFORMATION uplift mountain building t ranspression Altyn Tagh fault TIBET
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Human Carrying Capacity of Rangeland Resources in China′s Mountain Areas
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作者 鲍文 《Animal Husbandry and Feed Science》 CAS 2009年第4期7-11,20,共6页
Based on analysis of the development potential of rangeland resources in China's mountain areas, the paper makes analysis and forecast in human carrying capacity of rangeland resources. It provides some reference for... Based on analysis of the development potential of rangeland resources in China's mountain areas, the paper makes analysis and forecast in human carrying capacity of rangeland resources. It provides some reference for drawing up the development strategy in mountain areas. 展开更多
关键词 China's mountain areas Rangeland resources Human carrying capacity
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求Duffing方程周期解的Mountain Pass方法 被引量:6
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作者 刘淑媛 吕显瑞 齐毅 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2007年第4期519-523,共5页
研究一类超线性Duffing方程周期解的存在性及其数值求解方法.利用山路引理证明了超线性Duffing方程周期解的存在性,并给出一种求Duffing方程周期解的Mountain Pass算法及其具体算例.
关键词 山路引理 临界点 P.s.条件 mountain Pass算法 超线性Dulling方程
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Relationships of climate change and tree ring of Betula ermanii tree line forest in Changbai Mountain 被引量:34
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作者 YU Da-pao GU Hui-yan +2 位作者 WANG Jian-dong WANG Qing-li DAI Li-min 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第3期187-192,共6页
Based on the tree-ring growth characteristics of Erman's birch (Betula ermanii charm.) and the relationships between it and climatic )'actors at elevation of 1950m, the sensitivity of tree lines in Changbai Mount... Based on the tree-ring growth characteristics of Erman's birch (Betula ermanii charm.) and the relationships between it and climatic )'actors at elevation of 1950m, the sensitivity of tree lines in Changbai Mountain to climatic factors was assessed. The results indicated tree line forest in Changbai Mountain had an obvious sensitivity to climate factors. However, difference from other study sits is that the main climatic control factor on tree-ring growth was not current growth season temperatures, as might be expected, but previous winter and current March temperature. Although the precipitation in the region was quite abundant, the tree-ring growth was still significantly correlated with the precipitation during previous winter and current spring. Additionally, climatic factors which influenced the Erman's birch growth were not the yearly variables, but seasonal and monthly variables. Therefore, the reported increase in yearly mean temperature and total yearly precipitation since 1980s was not responded by sustained increase in ring widths in recent decades. 展开更多
关键词 Climatic change dendrochronology Erman's birch Tree line in Changbai mountain
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Relationship between excessive erythrocytosis and acute mountain sickness: A field study 被引量:4
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作者 Xiao-Han Ding Ji-Hang Zhang +1 位作者 Bin Cui Lan Huang 《Journal of Medical Colleges of PLA(China)》 CAS 2014年第2期84-88,共5页
Background: Alterations in hematology, especially erythroid changes, may be involved in acute mountain sickness(AMS) at high altitude. This study aimed to identify the relationship between excessive erythrocytosis and... Background: Alterations in hematology, especially erythroid changes, may be involved in acute mountain sickness(AMS) at high altitude. This study aimed to identify the relationship between excessive erythrocytosis and AMS following different durations of high-altitude exposure.Methods: A total of 692 healthy young Chinese men were recruited for the study in June and July of 2012 and were divided into the following five groups: I) the 24-h group(24 hours after arrival at Lhasa, 3,700 m, n=261); II) the 7-d group(exposed at Lhasa, 3,700 m for seven days, n=99); III) the re-exposure group(re-exposed at Yang Bajing, 4,400 m for seven days after 】1 year of acclimation at 3,700 m, n=94); IV) the acclimated group(】1 year of acclimation at 3,700 m, Lhasa, n=42); and V) the sea-level control(control group, Chengdu, n=196). Case report forms were used to record the subjects’ demographic information and AMS-related symptoms. All of the subjects underwent routine blood tests.Results: The red blood cell(RBC) count fell slightly but was not significant upon acute exposure to high altitude, whereas the hemoglobin concentration([Hb]) increased significantly. After high-altitude re-exposure, both of the [Hb] and RBC count showed significant increases. The incidence of AMS was 65.1%, 26.3% and 51.1%, respectively in the 24-h, 7-d and re-exposure groups. The [Hb](P=0.024) and hematocrit(P=0.017) were greater in the AMS+ individuals than in the AMS– individuals in 7-d group. A correlation analysis revealed that the [Hb] and hematocrit were closely related with AMS score in 7-d and re-exposure groups, while the RBC showed a correlation with AMS score only in the re-exposure group. The AMS incidence was lowest when the [Hb] was between 140 and 160 g/L in the 24-h and 7-d groups.Conclusions: AMS is associated with both [Hb] and excessive erythrocytosis. Additionally, our findings indicate the existence of an optimal [Hb] for preventing AMS. 展开更多
关键词 HEMATOLOGY high altitude EXPOsURE acute mountain sickness
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Strain data recorded in Xinjiang and their bearing on Tianshan’s uplift/shortening and Tarim basin’s rotation 被引量:1
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作者 Jiang Jingxiang Wu Guodong Yin Guanghua Gao Ge Wang Zaihua Li Jie 《Geodesy and Geodynamics》 2011年第1期21-28,共8页
Based on the continuous strain data recorded in Xinjiang since 1985, we discuss the mechanisms of Tianshan' s uplift and Tarim basin' s clockwise rotation. The results indicate : 1 ) The principal - compression di... Based on the continuous strain data recorded in Xinjiang since 1985, we discuss the mechanisms of Tianshan' s uplift and Tarim basin' s clockwise rotation. The results indicate : 1 ) The principal - compression directions in Tianshan are nearly NS, and their intersection angles with regional structures and mountains are nearly perpendicular, which is in accordance with Tianshan' s uplift and crustal shortening. 2)The principal compressions around Tarim basin tend to facilitate the regional faults' left-lateral strike-slip movements and the basin' s clockwise rotation. These phenomena of uplift/shortening and rotation are fundamentally the re- suits of India plate' s northward push on Euro-Asia plate, and the associated Pamir arc ' s rapid northward movement and regional blocks' interaction. 展开更多
关键词 continuous borehole strain measurement principal-compression direction Tianshan uplift Nscrustal shortening Tarim basin's clockwise rotation
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Determination of the Neoproterozoic Shicaogou Syn-collisional Granite in the Eastern Qinling Mountains and Its Geological Implications 被引量:21
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作者 CHENDanling LIULiang +4 位作者 SUNYong ZHANGAnda ZHANGChengli LIUXiaoming LUOJinhai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期73-82,共10页
The Shicaogou granite has been identified as a magnesian (Fe-number=0.71-0.76), calcic to calc-alkalic (MALI=3.84-5.76) and peraluminous (ASI=1.06-1.13) granite of the syn-collisional S-type, with high SiO2(>71%), ... The Shicaogou granite has been identified as a magnesian (Fe-number=0.71-0.76), calcic to calc-alkalic (MALI=3.84-5.76) and peraluminous (ASI=1.06-1.13) granite of the syn-collisional S-type, with high SiO2(>71%), A12O3 (>13%) and Na2O+K2O (6.28%-7.33%, equal for NaO2 and K2O). Trace element and REE analyses show that the granite is rich in LILE such as of Rb, Sr, Ba and Th, and poor in HFSE like Yb, Y, Zr and Hf. Its Rb/Sr ratio is greater than 1; the contents of Nb and Ta, and the ratio of Nb/Ta as well as the REE geochemical features (e.g. REE abundance, visible fractionation of LREE and HREE and medium to pronounced negative Eu anomalies) are all similar to those of crust-origin, continent-continent syn-collisional granite. Moreover, the granite exhibits almost the same pattern as that of the typical continent-continent syn-collisional granite on the spider diagram and all samples fall within the syn-collisional granite field.The cathodoluminescence (CL) investigations have revealed that the zircon from the Shicaogou granite represents a typical magmatic product characterized by its colorless, transparent and euhedral crystals, and distinct zoning of oscillatory bands. Residual cores of irregular zircon can be found in a few enhedral grains. Trace element studies of the zircon grains, with high contents of P, Y, Hf, Th, U and REE and high ratios of Th/U, obviously positive Ce anomalies and HREE enrichment compared to LREE, also result in the same conclusion.The LA-ICP-MS U-Pb isotopic data from 24 spots of 21 zircon grains demonstrate that 20 spots in the oscillatory zone yield an average weighted 206Pb/238U age of 925±11 Ma, indicating that the Shicaogou granite was formed in the Neoproterozoic. Combined with other Neoproterozoic syn-collisional granites found in the study area, the present geochronological determination can further reveal that collision-amalgamation events could have occurred among some continental blocks in the Qinling orogenic belt during the Neoproterozoic. This in turn provides an accurate chronological constraint on the Neoproterozoic break-up and convergence in the belt. 展开更多
关键词 LA-ICP-Ms U-Pb dating ZIRCON syn-collisional s-type granite geological implication shicaogou eastern Qinling mountains
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Influence of Flow Regime on the Vegetation Zonation along Mountain Streams in the Western Cape, South Africa 被引量:1
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作者 Erwin Jacobus Joannes SIEBEN 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1484-1498,共15页
Zonation patterns of riparian vegetation have been sampled and described in mountain streams in two catchments in the Hottentots-Holland Mountains, Western Cape, South Africa. Six main vegetation types that differ in ... Zonation patterns of riparian vegetation have been sampled and described in mountain streams in two catchments in the Hottentots-Holland Mountains, Western Cape, South Africa. Six main vegetation types that differ in structure and species composition, are dominant along these river banks: Aquatic vegetation, Wetbanks, Palmiet, Scrub, Forest and Shrubland(Fynbos). The study aims to correlate the vegetation patterns to flooding patterns, in particular the inundation frequency and stream power. A problem arises: because these catchments are ungauged, like most mountain catchments, with the only weirs at the downstream end of the catchment. Discharge data at the weirs are extrapolated to the sites upstream by multiplication with a factor based on the size of the subcatchment that drains through a sample site. In this way, recurrence intervals for floods in mountain streams are derived. Discharges at sites are also calculated using bed roughness(Manning's n) and slope in straight sections with uniform flow conditions. Stream power is derived from the discharges calculated in this manner. The combination of stream power and recurrence intervals explains the occurrence of most vegetation types occurring on the banks, except for one type: Afromontane Forest. This type is probably more dependent on other factors, such as protection from fire and the depth of the groundwater table. 展开更多
关键词 Hydrology Hydraulics Riparian vegetation mountain streams Floods stream power Manning's n.
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Topography,structural and exhumation history of the Admiralty Mountains region,northern Victoria Land,Antarctica
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作者 Maria Laura Balestrieri Valerio Olivetti +3 位作者 Federico Rossetti Cecile Gautheron Silvia Catto Massimiliano Zattin 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第5期1841-1858,共18页
The Admiralty Mountains region forms the northern termination of the northern Victoria Land,Antarctica.Few quantitative data are available to reconstruct the Cenozoic morpho-tectonic evolution of this sector of the An... The Admiralty Mountains region forms the northern termination of the northern Victoria Land,Antarctica.Few quantitative data are available to reconstruct the Cenozoic morpho-tectonic evolution of this sector of the Antarctic plate,where the Admiralty Mountains region forms the northern termination of the western shoulder of the Mesozoic-Cenozoic West Antarctica Rift System.In this study we combine new low-temperature thermochronological data(apatite fission-track and(U-Th-Sm)/He analyses)with structural and topography analysis.The regional pattern of the fission-track ages shows a general tendency to older ages(80-60 Ma)associated with shortened mean track-lengths in the interior,and younger fission-track ages clustering at 38-26 Ma with long mean track-lengths in the coastal region.Differently from other regions of Victoria Land,the younger ages are found as far as 50-70 km inland.Single grain apatite(U-Th-Sm)/He ages cluster at 50-30 Ma with younger ages in the coastal domain.Topography analysis reveals that the Admiralty Mountains has high local relief,with an area close to the coast,180 km long and 70 km large,having the highest local relief of>2500 m.This coincides with the location of the youngest fission-track ages.The shape of the area with highest local relief matches the shape of a recently detected low velocity zone beneath the northern TAM,indicating that high topography of the Admiralty Mountains region is likely sustained by a mantle thermal anomaly.We used the obtained constraints on the amount of removed crustal section to reconstruct back-eroded profiles and calculate the erosional load in order to test flexural uplift models.We found that our back-eroded profiles are better reproduced by a constant elastic thickness of intermediate values(Te=20-30 km).This suggests that,beneath the Admiralty Mountains,the elastic properties of the lithosphere are different with respect to other TAM sectors,likely due to a stationary Cenozoic upper mantle thermal anomaly in the region. 展开更多
关键词 ANTARCTICA THERMOCHRONOLOGY Transantarctic mountains Rift margin uplift
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Foliar carbohydrate differs between Picea crassifolia and Sabina przewalskii with the altitudinal variation of Qilian Mountains, China
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作者 ManXiao Zhang HuiJuan Pei +2 位作者 YouFu Zhang Tuo Chen GuangXiu Liu 《Research in Cold and Arid Regions》 CSCD 2015年第2期180-188,共9页
Nonstructural carbohydrates (NSC) and nitrogen metabolism strongly influence growth and development in plants. The biosynthesis of cellulose and lignin (structural carbohydrates, SC) depends largely on the supply ... Nonstructural carbohydrates (NSC) and nitrogen metabolism strongly influence growth and development in plants. The biosynthesis of cellulose and lignin (structural carbohydrates, SC) depends largely on the supply of NSC. We desire to examine which hypothesis, carbon limitation or growth limitation, best fits the alpine plant response between NSC, SC, carbon (C), nitrogen (N) and altitude. We compared the foliar concentrations of carbohydrates, C and N between the leaves of Picea crassifolia (lower-elevation tree-line species) and Sabina przewalskii (high-elevation tree-line species) in their response to changing elevation. Our site was located in the mid-northern area of Qilian Mountains, China. We found that foliar soluble sugar (SG) concentrations were significantly higher in P. crassifolia than in S. przewalskii at the 2,700-3,400 m level. Foliar NSC levels in R crassifolia increased at the 2,700-3,100 m level, indicating that growth was limited gradually resulting in a surplus of NSC (to conform to GLH), subsequently decreasing at the 3,100-3,400 m level, the assimilation declined leading to C deficit (to conform to CLH). SC (SC metabolism disorders at 3,100-3,400 m), C, N and starch were significantly lower in R crassifolia than in S. przewalskii. Conversely, foliar SG concentration shows a fall-rise trend with increasing elevation for S. przewalskii. SC concentration in S. przewalskii leaves decreased with an increase of elevation and has a significantly positive correlation to N concentration marking the assimilation of plants. Therefore, the high-elevation tree-line species (S. przewalskii) utilize or store more foliar SG leading to a decrease of SG concentration for survival and growth/regrowth in an adverse environment, higher total C, N, SC, starch contents and lower NSC level. Also, their change trends along the elevational gradient in leaves orS. przewalskii indicate better assimilation strategies for SG use under environmental stress compared to P. crassifolia. This indicates that foliar C metabolism along the elevation follows the principle of the growth-limitation hypothesis (GLH) or carbon limitation hypothesis (CLH), which depends on the acclimation of different alpine life-forms to the environment. 展开更多
关键词 nonstructural carbohydrates structural carbohydrate ALTITUDE Qilian mountain P. crassifolia s. przewalskii
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The protective effect of cyclodextrin on the color quality and stability of Cabernet Sauvignon red wine 被引量:1
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作者 Caiyun Liu Lulu Wu +2 位作者 Shuyue Fan Yongsheng Tao Yunkui Li 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期310-323,共14页
The impact of cyclodextrins(CDs)on wine quality and stability remains largely unknown.This study systematically assessed the protective effect of the post-fermentation addition of CDs on color stability of red wine fr... The impact of cyclodextrins(CDs)on wine quality and stability remains largely unknown.This study systematically assessed the protective effect of the post-fermentation addition of CDs on color stability of red wine from the viewpoints of color characteristics,copigmentation and phenolic profiles.The grey relational analysis(GRA)and principal component analysis(PCA)methods were employed to dissect the key effective determinants related to color quality.The addition of CDs induced a significant hyperchromic effect of 8.19-25.40%,a significant bathochromic effect and an enhancement of the color intensity.Furthermore,the evolution of anthocyanin forms and the content of monomeric anthocyanins revealed that β-CD is a superior favorable cofactor during wine aging,but for long-term aging,2-HP-β-CD and 2-HP-γ-CD are more beneficial in promoting the formation of polymerized anthocyanins and color stability.This work provides an important reference for the use of CDs to enhance the color quality and stability of red wines. 展开更多
关键词 cyclodextrins color properties copigmentation Helan mountains East Foothill red wine aging
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Uplift Resistance Calculation and Sensitive Analysis of Jack-up Wind Installation Vessels
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作者 刘志杰 刘晓宇 +1 位作者 孙德平 林成新 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期210-214,共5页
The uplift resistance calculation is an important basis for the construction decisions of the jack-up wind installation vessel and the design of the jacking system,and determines the operation risk and reliability in ... The uplift resistance calculation is an important basis for the construction decisions of the jack-up wind installation vessel and the design of the jacking system,and determines the operation risk and reliability in the installation process of the wind turbine. The influence factors of the pile shoe's penetration depth and uplift resistance are analyzed,and the calculation model and flow of the uplift resistance are given. Based on a construction example,the influence rules are analyzed for the change of the pile shoe's structural parameters on the penetration depth and uplift resistance.The analysis results show that the penetration depth is more sensitive to the width of the pile shoe,and the height has greater influence on the uplift resistance than the length and width of the spud. With the increase of the height,the uplift resistance may increase rapidly.Although the decreases of the length,width and height of the pile shoe may reduce the uplift resistance,the penetration depth may increase in the meantime. This will increase the pulling pile time and reduce the construction efficiency. So the parameters of the pile shoe should be optimized according to the adaptable geology condition so as to obtain the optimal uplift resistance and working efficiency. 展开更多
关键词 jack-up wind installation vessel uplift resistance penetration depth pile shoe’s structural parameters
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Comparing mineral weathering and elemental transport between earth's critical zone with different parent rocks in Yanshan Mountain,Hebei province,China
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作者 Zijian Sun Zhen Liao +7 位作者 Wei Shen Daqing Fu Xiaofeng Wei Huiqiong Zhang Ziran Chen Lianghui Xiong Tianhao An Hao Wei 《Acta Geochimica》 EI CAS CSCD 2022年第6期982-999,共18页
Bedrock weathering performs a significant influence on the evolution of Earth’s critical zone.Carbonate rock(dolostone),metamorphic rock(gneiss),and sedimentary rock(sandstone)geological formations in Yanshan Mountai... Bedrock weathering performs a significant influence on the evolution of Earth’s critical zone.Carbonate rock(dolostone),metamorphic rock(gneiss),and sedimentary rock(sandstone)geological formations in Yanshan Mountain,Hebei Province,are taken as objects to probe the controlling of geological formations on weathering characteristics,migration,and enrichment of elements as well as structure of Earth’s critical zone under the identical climate conditions through geological field survey,analysis on minerals component,element distribution in the weathering profile.The dolostone geological formation(DGF)is lithologically dominated by dolostone,characterized by the strongest and predominant chemical weathering.During bedrock weathering and pedogenesis,DGF is marked by significant depletion of CaO,Mg O,S,Mn,Mo and enrichment of N,K,Fe_(2)O_(3),and Zn with concentrations of P,Cu,and B keeping stable.Shortage of soil-forming materials and significant loss are driven by soil erosion,which results in thin regolith and soil.The soil thickness is less than 10 cm,and the regolith thickness is less than 30 cm.The vegetation community is predominantly rock arbor or brush,which is calcivorous and tolerant of barrenness.Plagiogneiss is a dominant rock type of gneiss geological formation(GGF),characterized by the weakest weathering and fast chemical and physical weathering rate.GGF is masked by significant depletion of P,K,CaO,MgO,Fe_(2)O_(3),Mn,Cu and enrichment of N,S,Mo,and B,with contents of Zn keeping stable.Both soil and regolith developed in GGF are relatively thick for one of the reasons that biotite expands during weathering.The soil thickness is more than 50 cm,and the regolith thickness ranges from 100 to 200 cm.The vegetation community is predominantly high-quality economic forests and various arbors because of the enrichment of nutrients in GGF.Sandstone is primarily a rock type of sandstone geological formation(SGF),characterized by moderate weathering degree and slow chemical weathering rate.SGF is marked by significant depletion of P,K,CaO,MgO,Fe_(2)O_(3),and enrichment of N,S,Mn,Cu,Zn,and Mo,with fluctuant changes of Zn and B.The thickness of soil developed in SGF varies between that of DGF and GGF.The soil thickness ranges from 30 to 50 cm,and the regolith thickness ranges from 50 to 100 cm.Chinese pines are widely spread on the shady slopes of SGF.Research provides theoretical support for screening dominant ecological resource areas,ecological industry development and ecological protection and restoration for Yanshan Mountain,Hebei Province. 展开更多
关键词 Yanshan mountain Earth’s critical zone Rock weathering PEDOGENEsIs Migration and enrichment of element
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