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Rock Magnetic Evidence for the Seismogenic Environment of Large Earthquakes in the Motuo Fault Zone,Eastern Himalayan Syntaxis 被引量:1
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作者 CAO Yong SUN Zhiming +5 位作者 GAO Yang LIU Jian LI Bin YANG Yuhan YE Hao XU Peng 《Acta Geologica Sinica(English Edition)》 2025年第3期896-907,共12页
Knowledge of the seismogenic environment of fault zones is critical for understanding the processes and mechanisms of large earthquakes.We conducted a rock magnetic study of the fault rocks and protoliths to investiga... Knowledge of the seismogenic environment of fault zones is critical for understanding the processes and mechanisms of large earthquakes.We conducted a rock magnetic study of the fault rocks and protoliths to investigate the seismogenic environment of earthquakes in the Motuo fault zone,in the eastern Himalayan syntaxis.The results indicate that magnetite is the principal magnetic carrier in the fault rocks and protolith,while the protolith has a higher content of paramagnetic minerals than the fault rocks.The fault rocks are characterized by a high magnetic susceptibility relative to the protolith in the Motuo fault zone.This is likely due to the thermal alteration of paramagnetic minerals to magnetite caused by coseismic frictional heating with concomitant hydrothermal fluid circulation.The high magnetic susceptibility of the fault rocks and neoformed magnetite indicate that large earthquakes with frictional heating temperatures>500℃have occurred in the Motuo fault zone in the past,and that the fault maintained an oxidizing environment with weak fluid action during these earthquakes.Our results reveal the seismogenic environment of the Motuo fault zone,and they are potentially important for the evaluation of the regional stability in the eastern Himalayan syntaxis. 展开更多
关键词 rock magnetism frictional heating seismogenic environment Motuo fault zone eastern himalayan syntaxis
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Characteristics of Massive Glacier-Related Watershed Geohazard Chains in the Eastern Himalayan Syntaxis,China 被引量:1
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作者 Shaohua Gao Yang Gao +4 位作者 Yueping Yin Bin Li Wenpei Wang Tiantian Zhang Haoyuan Gao 《Journal of Earth Science》 2025年第3期1181-1197,共17页
Frequent glacier-related watershed geohazard chains are causing severe damage to life and infrastructure,reported consistently from the Eastern Himalayan Syntaxis.This paper presents a systematic method for researchin... Frequent glacier-related watershed geohazard chains are causing severe damage to life and infrastructure,reported consistently from the Eastern Himalayan Syntaxis.This paper presents a systematic method for researching geohazard,from regional to individual scale.The methodology includes the establishment of geological chain inventories,discrimination of geohazard chain modes,analyses of dynamics and dam breaches,and risk assessments.The following results were obtained:(1)In the downstream of Yarlung Zangbo River,175 sites were identified as high-risk for river blockage disasters,indicating the development of watershed geohazards.Five geohazard chain modes were summarized by incorporating geomorphological characteristics,historical events,landslide zoning,and materials.The risk areas of typical hazard were identified and assessed using InSAR data.(2)Glacier-related watershed geohazard chains are significantly different from traditional landslides.A detailed inversion analysis was conducted on the massive rock-ice avalanche in the Sedongpu gully in 2021.This particular event lasted roughly 300 seconds,with a maximum flow velocity of 77.2 m/s and a maximum flow height of 93 meters.By scrutinizing the dynamic processes and mechanical characteristics,mobility stages and phase transitions can be divided into four stages.(3)Watershed geohazard chains tend to block rivers.The peak breach discharge of the Yigong Landslide reached 12.4×10^(4) m^(3)/s,which is 36 times the volume of the seasonal flood discharge in the Yigong River.Megafloods caused by landslide dam breaches have significantly shaped the geomorphology.This study offers insights into disaster patterns and the multistaged movement characteristics of glacier-related watershed geohazard chains,providing a comprehensive method for investigations and assessments in glacial regions. 展开更多
关键词 glacier-related watershed geohazard chains geohazard chain modes secondary hazards InSAR Eastern himalayan Syntax DISASTERS glaciers
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Lithium-rich tourmaline in Himalayan leucogranite:An example from the Gabo Li-rich granite-pegmatite system,Xizang,China
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作者 Hongzhao Shi Yiyun Wang +3 位作者 Linkui Zhang Hong Liu Weikang Guo Jiangang Fu 《Acta Geochimica》 2025年第2期297-313,共17页
The Gabo lithium deposit represents a newly discovered pegmatite-type lithium deposit within the Himalayan metallogenic belt.The tourmaline-muscovite granite,the largest leucogranite in the mining area,displays a clos... The Gabo lithium deposit represents a newly discovered pegmatite-type lithium deposit within the Himalayan metallogenic belt.The tourmaline-muscovite granite,the largest leucogranite in the mining area,displays a close spatial correlation with the Li-pegmatite veins.This study aims to examine the genesis of tourmaline and evaluate the significance and potential of pegmatite lithium deposits.Tourmaline is extensively distributed in tourmaline-muscovite granite at Gabo deposit in Luozha county(Xizang).Investigation of the compositional and in situ boron isotopes of the tourmaline revealed that the tourmalines mainly belong to the schorl group and exhibit uniform elevated Li-Sn contents andδ^(11)B values(-11.6‰to-10.5‰).This indicates that the tourmaline mainly crystallized from a boron-rich granitic magma undergoing enrichment in elemental lithium during the tourmaline crystallization process.Compared with the principal rare metal leucogranite-pegmatites in the Himalayan orogen,it is proposed that the elevated lithium(Li)content of tourmaline serves as an eff ective mineral indicator for the highly evolved pegmatite-type rare metal deposits. 展开更多
关键词 TOURMALINE Genetic relationship Pegmatitic deposit Gabo himalayan metallogenic belt
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Explore the gift of nature—Himalayan salt
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作者 秦虞 《疯狂英语(新读写)》 2025年第3期35-37,76,共4页
1 Himalayan salt,a pink organic variety of the essential food sourced from Pakistan,is becoming increasingly popular in China,fueled by growing demand from quality‑conscious consumers.Himalayan salt is on the dining t... 1 Himalayan salt,a pink organic variety of the essential food sourced from Pakistan,is becoming increasingly popular in China,fueled by growing demand from quality‑conscious consumers.Himalayan salt is on the dining tables of more Chinese consumers on occasions such as camping,barbecue parties and grilling steak at home,and it has been used to improve taste and for decorative purposes. 展开更多
关键词 grilling steak himalayan salt improve taste dining tables pink salt CAMPING quality conscious consumers barbecue parties
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Population and conservation status of the Himalayan Griffon(Gyps himalayensis) at the Drigung Thel Monastery,Tibet,China 被引量:3
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作者 刘超 霍志萍 于晓平 《Chinese Birds》 CSCD 2013年第4期328-331,共4页
The Himalayan Griffon(Gyps himalayensis), occurring mainly in the Tibetan Plateau, is one of the scavengers of Old World vultures. As of now, knowledge about the Himalayan Griffon in China remains scarce. Estimates of... The Himalayan Griffon(Gyps himalayensis), occurring mainly in the Tibetan Plateau, is one of the scavengers of Old World vultures. As of now, knowledge about the Himalayan Griffon in China remains scarce. Estimates of its number, habitat, and conservation status were carried out in 2003, 2009 and 2102 in the Lhasa River Valley, where we paid particular attention to the population living at the Drigung Thel Monastery, Mzizhokunggar County. The resident species occupies alpine meadows in the daytime and roosts at the upper parts of cliffs at night between 4400–5000 m elevation. The number of individual birds of the Himalayan Griffon around the monastery was estimated as 230 in 2003, 250 in 2009 and 200 in 2012. This population is considered relatively stable, thanks to the current conservation measures by Buddhist monks and local people. Given the lack of any baseline information, it is difficult for us to recommend and provide any effective conservation measures. 展开更多
关键词 himalayan Griffon HABITAT POPULATION conservation status
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Himalayan Monal(Lophophorus impejanus):distribution,habitat and population status in Tibet,China
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作者 马小春 郭俊峰 于晓平 《Chinese Birds》 2011年第3期157-162,共6页
The Himalayan Monal (Lophophorus impejanus) is a national first grade protected species in China.So far,current knowledge of the Himalayan Monal in China is still poor.An estimate of its distribution,numbers and habit... The Himalayan Monal (Lophophorus impejanus) is a national first grade protected species in China.So far,current knowledge of the Himalayan Monal in China is still poor.An estimate of its distribution,numbers and habitat was conducted during a two-year investigation from 2008 to 2009 in southern Tibet,especially in Lhozhag,Cona and Yadong counties.In total,12 sightings of the Himalayan Monal were recorded during the study period.Our data suggest that this bird is mainly found in Medog,Zayu,Cona,Lhunze,Lhozhag,Nyalam,Dingjie,Gamba and Yadong counties on the southern slopes of the Himalayas.Its western-most location was confirmed to be Nyalam County.The bird ranges in elevation from 3800 to 4300 m in the summer and from 3200 to 3500 m in the winter.We sighted 36-37 individual birds,consisting of 8-10 males,16-20 females and 7-8 sub-adults inhabiting the area around the Kajiu Monastery in Lhozhag County.The birds are mainly found in rocky forests,interspersed with steep slopes,cliffs and alpine meadows at elevations between 3800 and 4000 m.The population density of the Himalayan Monal near the Kajiu Monastery is 2.03 individual birds per km2,much larger than that of Yadong and Cona counties (0.052 individuals per krn2). 展开更多
关键词 himalayan Monal DISTRIBUTION HABITAT population density
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Structural and Chronological Evidence for the India-Eurasia Collision of the Early Paleocene in the Eastern Himalayan Syntaxis, Namjagbarwa 被引量:10
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作者 张进江 季建清 +2 位作者 钟大赉 桑海清 何顺东 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2002年第4期446-454,共9页
The eastern Himalayan syntaxis in Namjagbarwa is a high-grade metamorphicterrain formed by the India-Eurasia collision and northward indentation of the Indian continent intoAsia. Right- and left-lateral slip zones wer... The eastern Himalayan syntaxis in Namjagbarwa is a high-grade metamorphicterrain formed by the India-Eurasia collision and northward indentation of the Indian continent intoAsia. Right- and left-lateral slip zones were formed by the indentation on the eastern and westernboundaries of the syntaxis respectively. The Dongjug-Mainling fault zone is the main shear zone onthe western boundary. This fault zone is a left-lateral slip belt with a large component ofthrusting. The kinematics of the fault is consistent with the shortening within the syntaxis, andthe slipping history along it represents the indenting process of the syntaxis. The Ar-Archronological study shows that the age of the early deformation in the Dongjug-Mainling fault zoneranges from 62 to 59 Ma. This evidences that the India-Eurasia collision occurred in the earlyPaleocene in the eastern Himalayan syntaxis. 展开更多
关键词 India-Eurasia collision eastern himalayan syntaxis Namjagbarwa structuralchronology Paleocene
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DEFORMATION OF THE EASTERN HIMALAYAN SYNTAXIS: EVIDENCES FROM STRUCTURES AND KINEMATICS OF ITS WESTERN BOUNDARY 被引量:5
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作者 Zhang J.,Zhong D.,Ding L.,Ji J.,He S(Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029,China) 《地学前缘》 EI CAS CSCD 2000年第S1期18-20,共3页
The western boundary of the Eastern Himalayan Syntaxis (EHS) is a deformation belt up to 30km wide (Fig.1). Trending ca. N35°E, it separates the Gangdise magmatic belt in the west from the gneiss of EHS in the ea... The western boundary of the Eastern Himalayan Syntaxis (EHS) is a deformation belt up to 30km wide (Fig.1). Trending ca. N35°E, it separates the Gangdise magmatic belt in the west from the gneiss of EHS in the east. Its rock association, mica\|schist, quartzite, marble, and amphibolite, can be traced to the south to Gangdise belt and they were probably metamorphosed from the sediments along Yarlung Zangbo. This belt consists of several intensive deformation zones, the largest one of which is along the belt’s western margin from Dongjug to Mainling and we called this ca. 10km wide shear zone as the Dongjug\|Mainling shear zone (DMSZ).DMSZ experienced earlier ductile shear and later ductile\|brittle normal faulting. The earlier deformation produced mylonitic rocks. Their foliation trends N30°~40°E and dips northwest with the angle ranging from 55°to 80°, steepening northeastward. The penetrative kinematic lineation in the rocks has a varying attitude along the trend of DMSZ. It dips southwest with an angle of ca.35° in the southwest near Mainling, whereas dips northeast in the northeast. Moreover, the northeast dipping lineation steepens northeastwards, e.g., its angle ranges form 30° to 45° in the segment from Serkyim La to Dongjug but becomes 60~70° in the northeast most in another zone near Parlung. Kinematic indicators show that the motion of DMSZ had a left\|lateral slipping component, but the vertical motion components were different in the southwest from the northeast. From Serkyim La to the northeast, DMSZ had a kinematics of NW plate (Gangdise belt) thrusting over the SE plate (EHS) and its thrusting component increased toward northeast. However, the DMSZ has a vertical motion with the SE plate (EHS) as the uplifting plate. 展开更多
关键词 EASTERN himalayan Syntaxis INDENTATION UPLIFT
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Earthquake swarms near eastern Himalayan Syntaxis along Jiali Fault in Tibet:A seismotectonic appraisal 被引量:8
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作者 Basab Mukhopadhyay Sujit Dasgupta 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第5期715-722,共8页
The seismotectonic characteristics of ten repeated earthquake swarm sequence within a seismic cluster along Jiali Fault in eastern Himalayan Syntaxis(EHS) have been analysed.The swarms are spatially disposed in and ar... The seismotectonic characteristics of ten repeated earthquake swarm sequence within a seismic cluster along Jiali Fault in eastern Himalayan Syntaxis(EHS) have been analysed.The swarms are spatially disposed in and around Yigong Lake(a natural lake formed by blocking of Yigong River by landslide) and are characterized by low magnitude,crustal events with low to moderate b values.Ms:mb discriminant functions though indicate anomalous nature of the earthquakes within swarm but are considered as natural events that occurred under condition of high apparent stress and stress gradients.Composite fault plane solutions of selected swarms indicate strike-slip sense of shear on fault planes;solution parameters show low plunging compression and tensional axes along NW-SE and NE-SW respectively with causative fault plane oriented ENE-WSW.dipping steeply towards south or north.The fault plane is in excellent agreement with the disposition and tectonic movement registered by right lateral Jiali Fault.The process of pore pressure perturbation and resultant ’r—t plot’ with modelled diffusivity(D = 0.12 m^2/s) relates the diffusion of pore pressure to seismic sequence in a fractured poro-elastic fluid saturated medium at average crustal depth of 15-20 km.The low diffusivity depicts a highly fractured interconnected medium that is generated due to high stress activity near the eastern syntaxial bent of Himalaya.It is proposed that hydro fracturing with respect to periodic pore pressure variations is responsible for generation of swarms in the region.The fluid pressure generated due to shearing and infiltrations of surface water within dilated seismogenic fault(Jiali Fault) are causative factors. 展开更多
关键词 Seismic swarm Eastern himalayan Syntaxis(EHS) Jial
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Estimation of Seismic Landslide Hazard in the Eastern Himalayan Syntaxis Region of Tibetan Plateau 被引量:8
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作者 DU Guoliang ZHANG Yongshuang +5 位作者 YANG Zhihua Javed IQBAL TONG Bin GUO Changbao YAO Xin WU Ruian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期658-668,共11页
The eastern Himalayan syntaxis is one of the most tectonically active and earthquake-prone regions on Earth where earthquake-induced geological disasters occur frequently and caused great damages. With the planning an... The eastern Himalayan syntaxis is one of the most tectonically active and earthquake-prone regions on Earth where earthquake-induced geological disasters occur frequently and caused great damages. With the planning and construction of Sichuan-Tibet highway, Sichuan-Tibet railway and hydropower development on the Yarlung Zangbo River etc. in recent years, it is very important to evaluate the seismic landslide hazard of this region. In this paper, a seismic landslide hazard map is produced based on seismic geological background analysis and field investigation using Newmark method with 10% PGA exceedance probabilities in future 50 years by considering the influence of river erosion, active faults and seismic amplification for the first time. The results show that the areas prone to seismic landslides are distributed on steep slopes along the drainages and the glacier horns as well as ridges on the mountains. The seismic landslide hazard map produced in this study not only predicts the most prone seismic landslide areas in the future 50 years but also provides a reference for mitigation strategies to reduce the exposure of the new building and planning projects to seismic landslides. 展开更多
关键词 probabilistic seismic hazard Newmark method seismic landslide the eastern himalayan syntaxis TIBET Proto-Tethys
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Climate change effects in the Western Himalayan ecosystems of India: evidence and strategies 被引量:5
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作者 Vindhya Prasad Tewari Raj Kumar Verma Klaus von Gadow 《Forest Ecosystems》 SCIE CSCD 2017年第3期232-240,共9页
Background: The fragile landscapes of the Himalayan region are highly susceptible to natural hazards, and there is ongoing concern about current and potential climate change impacts. This study provides background in... Background: The fragile landscapes of the Himalayan region are highly susceptible to natural hazards, and there is ongoing concern about current and potential climate change impacts. This study provides background information on India's Western Himalayas and reviews evidence of warming as well as variability in precipitation and extreme events.Methods: Understanding and anticipating the impacts of climate change on Himalayan forest ecosystems and the services they provide to people are critical. Efforts to develop and implement effective policies and management strategies for climate change mitigation and adaptation requires particular new research initiatives. The various studies initiated and conducted in the region are compiled here.Results: Several new initiatives taken by the Himalayan Forest Research Institute in Shimla are described. This includes new permanent observational field studies, some with mapped trees, in high altitude transitional zones for continuous monitoring of vegetation response. We have also presented new strategies for mitigating potential climate change effects in Himalayan forest ecosystems.Conclusions: Assessment of the ecological and genetic diversity of the Himalayan conifers is required to evaluate potential responses to changing climatic conditions. Conservation strategies for the important temperate medicinal plants need to be developed. The impact of climate change on insects and pathogens in the Himalayas also need to be assessed. Coordinated efforts are necessary to develop effective strategies for adaptation and mitigation. 展开更多
关键词 himalayan ecosystem Climate change New strategies High altitude New observational studies
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Water in the Thickened Lower Crust of the Eastern Himalayan Orogen 被引量:5
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作者 Li Zhang Yu Ye +1 位作者 Shan Qin Zhenmin Jin 《Journal of Earth Science》 SCIE CAS CSCD 2018年第5期1040-1048,共9页
Water content in nominally anhydrous minerals (NAMs) of the high-pressure (HP) metamorphic rocks controls the thermal structure, rheology and partial melting of orogenic belts. This paper conducts a systematic ana... Water content in nominally anhydrous minerals (NAMs) of the high-pressure (HP) metamorphic rocks controls the thermal structure, rheology and partial melting of orogenic belts. This paper conducts a systematic analysis of water in NAMs of the HP granulites from the Greater Himalayan Sequence (GHS), representing the thickened lower crust of the eastern Himalayan Orogen. The present result shows that the garnet, clinopyroxene, feldspar, quartz and kyanite contain 188 ppm-432 ppm, 193 ppm-547 ppm, 335 ppm-1 053 ppm, 125 ppm-185 ppm and 89 ppm H2O, respectively, and indicates that the thickened lower crust of the Himalayan Orogen is relatively wet rather than dry. The considerable concentrations of water in the HP granulites are expected to promote the rheological weakening of the metamorphic core of the Himalayan Orogen, providing a favorable evidence for the channel flow model of the exhumation of thickened lower crust. 展开更多
关键词 micro-FTIR (Fourier transform infrared spectroscopy) water content GRANULITE himalayan Orogen.
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Observed changes in surface air temperature and precipitation in the Hindu Kush Himalayan region over the last 100-plus years 被引量:11
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作者 REN Yu-Yu REN Guo-Yu +6 位作者 SUN Xiu-Bao Arun Bhakta SHRESTHA YOU Qing-Long ZHAN Yun-Jian Rupak RAJBHANDARI ZHANG Pan-Feng WEN Kang-Min 《Advances in Climate Change Research》 SCIE CSCD 2017年第3期148-156,共9页
In this paper, we analyzed the long-term changes in temperature and precipitation in the Hindu Kush Himalayan (HKH) region based on climate datasets LSAT-V1.1 and CGP1.0 recently developed by the China Meteorological ... In this paper, we analyzed the long-term changes in temperature and precipitation in the Hindu Kush Himalayan (HKH) region based on climate datasets LSAT-V1.1 and CGP1.0 recently developed by the China Meteorological Administration. The analysis results show that during 1901e2014 the annual mean surface air temperature over the whole HKH has undergone a significant increasing trend. We determined the change rates in the mean temperature, mean maximum temperature, and mean minimum temperature to be 0.104 C per decade, 0.077 C per decade, and 0.176 C per decade, respectively. Most parts of the HKH have experienced a warming trend, with the largest increase occurring on the Tibetan Plateau (TP) and south of Pakistan. The trend of precipitation for the whole HKH is characterized by a slight decrease during 1901e2014. During 1961e2013, however, the trend of the annual precipitation shows a statistically significant increase, with a rate of 5.28% per decade and has a more rapid increase since the mid-1980s. Most parts of northern India and the northern TP have experienced a strong increase in the number of precipitation days (daily rainfall 1 mm), whereas Southwest China and Myanmar have experienced a declining trend in precipitation days. Compared to the trends in precipitation days, the spatial pattern of trends in the precipitation intensity seems to be more closely related to the terrain, and the higher altitude areas have shown more significant upward trends in precipitation intensity during 1961e2013. 展开更多
关键词 Climate change Temperature PRECIPITATION Trend HINDU Kush himalayan TIBETAN PLATEAU
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Diversity, Distribution Pattern and Conservation Status of the Plants Used in Liver Diseases/Ailments in Indian Himalayan Region 被引量:2
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作者 S.S. Samant Shreekar Pant 《Journal of Mountain Science》 SCIE CSCD 2006年第1期28-47,共20页
In the Indian Himalayan Region, th studies focused on diversity of the plants used fo treating liver diseases/ailments have not been carried out so far. Therefore, the present attempt has been made to study the divers... In the Indian Himalayan Region, th studies focused on diversity of the plants used fo treating liver diseases/ailments have not been carried out so far. Therefore, the present attempt has been made to study the diversity, distribution pattern and conservation status of the plant species used fo treating liver diseases/ailments in that region. A tota of 138 species (35 species of trees, 22 shrubs and 8 herbs) belonging to 98 genera in 60 families hav been recorded. Amongst the families, Euphorbiacea (9 species), and altitudinal zone <1,800 m, (i.e., 11 species) are rich in species. Traditionally, variou plant parts, such as roots/rhizomes/tubers (46 species), leaves (31), whole plants (30), barks (15) fruits (13), seeds and unspecified parts (8 each), and inflorescence (1) are used for the treatment of live diseases/ailments. 34 species are native, 3 ar endemic and 15 near endemic. 7 species ar categorized as Critically Endangered (Betula utilis) Endangered (Podophyllum hexandrum, Ephedra gerardiana, and Nardostachys grandiflora) and Vulnerable (Bergenia ligulata, B. stracheyi, and Hedychium spicatum) using new IUCN criteria Available chemical composition of plant parts used fo the treatment of liver diseases/ailments have beengiven. Assessment of the populations of threatened species, development of an appropriate strategy, action plan for the conservation and sustainable utilization of such components of plant diversity are suggested. 展开更多
关键词 Indian himalayan Region DIVERSITY liver ailments chemical composition NATIVE ENDEMIC critically endangered ENDANGERED
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THE EFFECT OF LESSER HIMALAYAN CALC-SILICATES ON THE ^(87)Sr/^(86)Sr OF THE BHOTE KOSI RIVER OF NEPAL—IMPLICATIONS FOR HIMALAYAN WEATHERING, THE MARINE ^(87)Sr/^(86)Sr RECORD AND GLOBAL CLIMATE 被引量:1
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作者 Lee Oliver 1,Nigel Harris 1, Nancy Dise 1,Mike Bickle 2 2 Department of Earth Sciences, Cambridge University, Cambridge CB2 3EQ, UK) 《地学前缘》 EI CAS CSCD 2000年第S1期396-397,共2页
During the last 40Ma the marine 87 Sr/ 86 Sr record shows a rapid rise (from 0 7078 to 0 7092) [1] , a trend which has been linked to the Himalayan Orogeny [2] . Indeed, many Himalayan rivers, principally those of the... During the last 40Ma the marine 87 Sr/ 86 Sr record shows a rapid rise (from 0 7078 to 0 7092) [1] , a trend which has been linked to the Himalayan Orogeny [2] . Indeed, many Himalayan rivers, principally those of the Ganges\|Brahmaputra system, display high 87 Sr/ 86 Sr relative to [Sr] [3] . Theories concerning the cause of this radiogenic Sr enrichment are diverse, but our results suggest that Lesser Himalayan carbonate\|rich lithologies play a vital role [4,5] .The Bhote Kosi originates in Tibet at ca.5km elevation from Tibetan Sedimentary Series (TSS) bedrock, before traversing the High Himalayan Crystalline Series (HHCS) and Lesser Himalaya (LH) of eastern Nepal, joining the Indrawati (at ca.0 6km elevation) to form the Sun Kosi, part of the Ganges system. Carbonates, calc\|silicates and silicates have been identified from the TSS, HHCS and LH, and the Bhote Kosi provides an opportunity to study the influence of these upon fluvial chemistry. Interest is focused on the cause of a rapid rise in riverine Sr\|isotope ratios immediately downstream of the Main Central Thrust (MCT) and the role of carbonate\|rich lithologies exposed in this section. Similar lithologies are lacking in the catchment of a second Nepalese river system, the Lantang Khola—Trisuli, sampled during the same period, and used as a baseline indicator for the effect of LH carbonates on the dissolved load of the Bhote Kosi. 展开更多
关键词 WEATHERING STRONTIUM ISOTOPES himalayan rivers CARBONATES
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Rhododendrons in Indian Himalayan Region: Diversity and Conservation 被引量:2
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作者 K. Chandra Sekar Sunil Kumar Srivastava 《American Journal of Plant Sciences》 2010年第2期131-137,共7页
The genus Rhododendron of Indian Himalayan Region (IHR) has been enumerated in the present paper. A total of 87 species, 12 subspecies and 8 varieties of Rhododendrons recorded in IHR, among these 6 species and one su... The genus Rhododendron of Indian Himalayan Region (IHR) has been enumerated in the present paper. A total of 87 species, 12 subspecies and 8 varieties of Rhododendrons recorded in IHR, among these 6 species and one subspecies are reported from Western Himalaya. The maximum concentration of 86% observed in Arunachal Pradesh (75 species). The species of Rhododendrons exhibit significant diversity in habit and broad range of distribution from the altitude of 800-6000 m. and the best range is observed in 3001-3500 m altitudes. In analysis revealed 20 taxa are endemic, 30 are rare, 24 are threatened / endangered, 3 are vulnerable and 47 taxa have to be assessed. The major threats to rhododendrons are deforestation and unsustainable extraction for firewood and incense by local people has been discussed. 展开更多
关键词 Rhododendrons INDIAN himalayan Region ERICACEAE INDIA
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Lesser Himalayan sequences in Eastern Himalaya and their deformation:Implications for Paleoproterozoic tectonic activity along the northern margin of India 被引量:7
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作者 Dilip Saha 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第3期289-304,共16页
Substantial part of the northern margin of Indian plate is subducted beneath the Eurasian plate during the Caenozoic Himalayan orogeny, obscuring older tectonic events in the Lesser Himalaya known to host Proterozoic ... Substantial part of the northern margin of Indian plate is subducted beneath the Eurasian plate during the Caenozoic Himalayan orogeny, obscuring older tectonic events in the Lesser Himalaya known to host Proterozoic sedimentary successions and granitic bodies. Tectonostratigraphic units of the Proterozoic Lesser Himalayan sequence (LHS) of Eastern Himalaya, namely the Daling Group in Sikkim and the Bomdila Group in Arunachal Pradesh, provide clues to the nature and extent of Proterozoic passive margin sedimentation, their involvement in pre-Himalayan orogeny and implications for supercontinent reconstruction. The Daling Group, consisting of flaggy quartzite, meta-greywacke and metapelite with minor mafic dyke and sill, and the overlying Buxa Formation with stromatolitic carbonate-quartzite- slate, represent shallow marine, passive margin platformal association. Similar lithostratigraphy and broad depositional framework, and available geochronological data from intrusive granites in Eastern Himalaya indicate strikewise continuity of a shallow marine Paleoproterozoic platformal sequence up to Arunachal Pradesh through Bhutan. Multiple fold sets and tectonic foliations in LHS formed during partial or complete closure of the sea/ocean along the northern margin of Paleoproterozoic India. Such deformation fabrics are absent in the upper Palaeozoic-Mesozoic Gondwana formations in the Lesser Himalaya of Darjeeling-Sikkim indicating influence of older orogeny. Kinematic analysis based on microstructure, and garnet composition suggest Paleoproterozoic deformation and metamorphism of LHS to be distinct from those associated with the foreland propagating thrust systems of the Caenozoic Himalayan collisional belt. Two possibilities are argued here: (1) the low greenschist facies domain in the LHS enveloped the amphibolite to granulite facies domains, which were later tectonically severed; (2) the older deformation and metamorphism relate to a Pacific type accretionary orogen which affected the northern margin of greater India. Better understanding of geodynamic evolution of the northern margin of India in the Paleoproterozoic has additional bearing on more refined model of reconstruction of Colllrnhia. 展开更多
关键词 Garnet composition Kinematics Lesser himalayan sequence Microstructure Paleoproterozoic Supercontinent
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An overview of studies of observed climate change in the Hindu Kush Himalayan (HKH) region 被引量:5
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作者 YOU Qing-Long REN Guo-Yu +5 位作者 ZHANG Yu-Qing REN Yu-Yu SUN Xiu-Bao ZHAN Yun-Jian Arun Bhakta SHRESTHA Raghavan KRISHNAN 《Advances in Climate Change Research》 SCIE CSCD 2017年第3期141-147,共7页
The Hindu Kush Himalayan (HKH hereafter) region is characterized by mountainous environments and a variety of regional climatic conditions. High-altitude regions in the HKH have the recent warming amplifications, espe... The Hindu Kush Himalayan (HKH hereafter) region is characterized by mountainous environments and a variety of regional climatic conditions. High-altitude regions in the HKH have the recent warming amplifications, especially during the global warming hiatus period. The rapid warming cause solid state water (snow, ice, glacier, and permafrost) to shrink, leading to increase in meltwater and there have been found more frequent incidences of flash floods, landslides, livestock diseases, and other disasters in the HKH region. Increasing awareness of climate change over the HKH region is reached a consensus. Meanwhile, the HKH region is often referred to as the water towers of Asia as many highaltitude regions store its water in the form of snow and/or glacier, feeding ten major large rivers in Asia. Therefore, the impacts of climate change on water availability in these river basins have huge influences on the livelihood of large number of population, especially in downstream regions. However, the scarcity of basic hydro-meteorological observations particularly in high-altitude regions of HKH limits rigorous analysis of climate change. Most studies used reanalysis data and/or model-reconstructed products to explore the spatial and temporal characteristics of hydro-meteorological processes, especially for extreme events. In this study, we review recent climate change in the HKH region, and the scientific challenges and research recommendations are suggested for this high-altitude area. 展开更多
关键词 Climate change HINDU Kush himalayan TIBETAN PLATEAU HYDROLOGICAL cycles
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RELATIONSHIP BETWEEN HIMALAYAN TECTONO-MAGNETIC MOVEMENT AND MINERALIZATION IN LANPING BASIN, YUNNAN PROVINCE 被引量:1
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作者 Teng Yanguo, Zhang Chengjiang, Peng Xiuhong, Ni Shijun, Liu Jiaduo(Chengdu University of Technology, Chengdu 610059,China) 《地学前缘》 EI CAS CSCD 2000年第S1期432-432,共1页
Lanping basin is located between Lancangjiang fault and Jinshajiang fault. Himalayan movement is the important tectogenesis, during which the activity of mid\|alkali magma is strong. For a long time, because the previ... Lanping basin is located between Lancangjiang fault and Jinshajiang fault. Himalayan movement is the important tectogenesis, during which the activity of mid\|alkali magma is strong. For a long time, because the previous had focused on studying porphyry copper, lead, zinc multi metal ore deposit in east uplift to this area, and they had ignored the relationship between Himalayan tectonomagnetic movement and multi\|metal mineralization in the basin.1 Characteristic of the Himalayan magmatic rock Himalayan magmatic rocks, a part of Himalayan porphyry zone, mainly distributed along Lijiang\|Beiya\|Weishan, which is the east to Lanping basin. There are a few magmatic rocks in the basin, a big scale of which is Yongping Zhuopan rock body, Yunlong Zaojiaochang rock body and Eryuan Shangyicun rock body. These magmatic rocks are mainly intrusion rocks and their characteristics are quartz syenite porphyry, alkalic rock, and granite porphyry. The ratio 87 Sr/ 86 Sr of rocks is 0 7046~0 7084, which reflects the magma source comes from mantle.The average isotopic age of these magmatic rocks is 40Ma. For example, Zhuopan rock body’s age of K\|Ar is 33 8Ma, Weishan rock body’s age of K\|Ar is 46 9Ma. 展开更多
关键词 MAGMATIC ROCKS himalayan tectonomagnetic TRACE element L anping basin
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Invasive Alien Plants of Indian Himalayan Region—Diversity and Implication 被引量:2
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作者 K. Chandra Sekar 《American Journal of Plant Sciences》 2012年第2期177-184,共8页
The present study deals with comprehensive list of Invasive alien plants of Indian Himalayan Region with background information on family, habit and nativity. A total of 190 invasive alien species under 112 genera, be... The present study deals with comprehensive list of Invasive alien plants of Indian Himalayan Region with background information on family, habit and nativity. A total of 190 invasive alien species under 112 genera, belonging to 47 families have been recorded. Among these, the dicotyledons represent by 40 families, 95 genera and 170 species;monocotyledons represent by 7 families, 17 genera and 20 species. The analysis of invasive species reveals that 18 species have been introduced intentionally, while the remaining species established unintentionally through trade. In terms of nativity, amongst 13 geographic regions, the majority of invasive plants reported from American continent (73%). While in life form analysis, the herbs (148 species) are dominant, followed by shrubs (19 species), Grass (11 species), Trees (4 species), sedges and climber (3 species each). Most of the invasive species are annual habit (63%). Apart from these, 90 species (47%) are being used by locals for medicinal purposes. A better planning is needed for early detection to control and reporting of infestations of spread of new and naturalized weeds to be monitored. 展开更多
关键词 INVASIVE ALIEN Species INDIAN himalayan Region NATIVITY India
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