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Evaluating farmers' strategies and socioeconomic drivers for adaptation to climate uncertainty: A case study in the Himalayan region of West Bengal,India
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作者 Sourakanti SARKAR Aishi MUKHERJEE +6 位作者 Auindrila BISWAS Subrata GORAIN Bimal BERA Anmol GIRI Malini ROY CHOUDHURY Suman DUTTA Sumanta DAS 《Regional Sustainability》 2026年第2期116-137,共22页
Climate change poses a profound threat to mountain agro-ecosystems,particularly in the Himalayan region of West Bengal,India,by disrupting precipitation patterns,increasing temperature variability,and intensifying ext... Climate change poses a profound threat to mountain agro-ecosystems,particularly in the Himalayan region of West Bengal,India,by disrupting precipitation patterns,increasing temperature variability,and intensifying extreme weather events.Despite growing evidence of climate change impacts,there remains a critical research gap in understanding how socioeconomic factors drive farmers' adaptation strategies to climate change in this vulnerable region.This study examines how farmers in the Himalayan region of West Bengal,India,perceived and responded to the growing impacts of climate change on mountain agro-ecosystems.Drawing on cross-sectional data from 370 farm households selected through multistage sampling,the research employs a combination of analytical tools,including the severity index(SI) to assess farmers' perceptions to climate change,the adaptation index(AI) to evaluate adaptive responses,the Garrett's ranking technique to prioritize constraints,and the ordered logistic regression to identify key socioeconomic drivers of adaptation.Findings reveal a high level of climate awareness among farmers,particularly regarding the increase in weather extremes(SI=74.87%),increase in temperature(SI=72.31%),and irregular rainfall patterns and highly erratic rainfall(SI=62.52%).The most commonly adopted strategies include adopting intercropping and mixed cropping systems(AI=0.613),adoption of the integrated farming system model(AI=0.600),and shift towards non-farm employment(AI=0.608),while the adoption of climate-resilient crop varieties and improved irrigation remains limited.Regression analysis highlights that education(regression coefficient=0.38),average landholding size(regression coefficient=1.21),and access to daily weather forecast information(regression coefficient=1.92) significantly promote adaptive behaviour,whereas age(regression coefficient= –0.09) and gender(regression coefficient= –0.76) are negatively associated.Institutional constraints,particularly unavailability of institutional credit,emerge as primary barriers.The study underscores the urgent need for region-specific,inclusive policy frameworks that enhance climate advisory services,support technology dissemination,and empower marginalized groups in the Himalayan region of West Bengal.By fostering informed,equitable,and resilient agricultural systems,these strategies can significantly strengthen the adaptive capacity of mountain farming communities and contribute to sustainable development under a changing climate. 展开更多
关键词 Adaptation index Severity index Climate change Adaptation strategies Garrett's ranking himalayan region
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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:3
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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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喜马拉雅造山带现今汇聚模式的数值模拟
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作者 田镇 于鑫 +2 位作者 李振洪 马星宇 王师迪 《地球物理学报》 北大核心 2026年第3期1018-1033,共16页
自~55 Ma以来,印度大陆与欧亚大陆的持续挤压、碰撞,使得喜马拉雅造山带成为了全球地壳运动最强烈、构造机理最复杂的地区之一,对其变形模式与动力机制的研究历来是地学界的前沿与热点.目前,虽已有部分研究初步解释了造山带局部的形变特... 自~55 Ma以来,印度大陆与欧亚大陆的持续挤压、碰撞,使得喜马拉雅造山带成为了全球地壳运动最强烈、构造机理最复杂的地区之一,对其变形模式与动力机制的研究历来是地学界的前沿与热点.目前,虽已有部分研究初步解释了造山带局部的形变特征,但基于区域动力背景与流变特性的精细动力学模拟仍较为匮乏,喜马拉雅弧整体的地壳汇聚模式仍存在较大争议.基于此,本文以喜马拉雅造山带震间GNSS速度场为约束,采用三维有限元数值模拟方法,建立了造山带径向汇聚、斜向汇聚以及黏弹性汇聚等动力学模型,揭示了喜马拉雅现今的形变机制与动力模式.结果显示:相比于径向汇聚模型,斜向汇聚模型的预测值与GNSS观测值的拟合度更高,说明了印度板块与青藏高原的汇聚既存在着径向运动(速率为18 mm·a^(−1)),还存在着与弧平行的运动(中段2 mm·a^(−1)、东段14 mm·a^(−1)).因此本文认为青藏高原南部广泛存在的拉张裂谷的构造动力很可能来源于印度—欧亚板块沿边界断裂所发生的斜向汇聚,这与重力垮塌或岩石圈地幔对流等假说有着一定的差异.另一方面,相比于弹性汇聚模型,考虑区域流变特性的黏弹性汇聚模型对远场GNSS观测值的拟合度更高,说明区域构造应力很可能引发了远场稳定的黏弹性变形,也意味着黏弹性的地学模型能够更精细、更合理地模拟造山带的动力过程.此外,黏弹性模型所估计的边界断裂闭锁深度为16 km,略低于弹性模型的结果.上述研究工作有助于我们从数值模拟角度全面、深刻地理解喜马拉雅现今可能的变形模式与板块汇聚机制. 展开更多
关键词 喜马拉雅造山带 有限元模拟 汇聚模式 黏弹性介质 动力学机制
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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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东喜马拉雅构造结核部早古生代花岗岩的成因
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作者 梁翼茹 丁慧霞 +3 位作者 张泽明 李中尧 王迪 张宇 《岩石学报》 北大核心 2026年第4期1350-1362,共13页
早古生代时期是冈瓦纳大陆演化的一个重要时期,包括大陆最终聚合和原特提斯洋俯冲。喜马拉雅造山带(印度大陆)位于冈瓦纳大陆的北缘,是其重要的组成部分。但其关于在该时期构造演化还存在争议。本文对东喜马拉雅构造结核部高喜马拉雅结... 早古生代时期是冈瓦纳大陆演化的一个重要时期,包括大陆最终聚合和原特提斯洋俯冲。喜马拉雅造山带(印度大陆)位于冈瓦纳大陆的北缘,是其重要的组成部分。但其关于在该时期构造演化还存在争议。本文对东喜马拉雅构造结核部高喜马拉雅结晶岩系中早古生代的花岗岩(现为花岗片麻岩)进行了详细的岩石学、年代学和地球化学研究。所研究的岩石由斜长石、钾长石、石英、黑云母、角闪石、石榴石、三元长石、蓝晶石、夕线石、绿帘石和褐帘石组成。锆石U-Pb年代学研究表明,其锆石具有明显的核-边结构,继承锆石为典型的岩浆锆石,其结晶年龄为~492Ma,锆石边部显示出变质锆石的特征,其年龄为~24Ma。所研究的岩石的SiO_(2)含量为59.1%~73.2%,铝饱和系数为0.8~1.1(其中一个样品为1.4),具有较低的MgO(0.61%~3.40%)和过渡族元素[Co(5.81×10^(-6)~23.9×10^(-6))和Ni(4.63×10^(-6)~52.3×10^(-6))]含量,总体上显示出中-酸性偏铝质-弱过铝质岩石的性质,另外其还表现出高钾钙碱性岩石的地球化学特征,同时,其富集大离子亲石元素(如,Th),相对亏损Nb、Ta和Ti,显示出典型弧岩浆岩的特征。此外,锆石核部微量元素特征也表明,这些片麻岩的原岩具有大陆弧岩浆岩的特征。研究表明这些岩石为基性下地壳部分熔融的产物。结合前人的研究成果,我们认为所研究的岩石其原岩形成在早古生代原特提洋俯冲过程中,后又在喜马拉雅造山过程中经历了新生代变质作用。 展开更多
关键词 早古生代 花岗岩 岩浆弧 新生代变质作用 东喜马拉雅构造结
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Kerguelen地幔柱早期活动新证据:藏东南隆子辉长岩年代学与地球化学制约
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作者 穆洎仲 康志强 +2 位作者 杨锋 吴玲玲 乔泽东 《现代地质》 北大核心 2026年第1期44-61,共18页
特提斯喜马拉雅带东段出露大规模早白垩世火成岩,其形成机制是否与东冈瓦纳大陆裂解有关备受学者们关注。本文以特提斯喜马拉雅带东段隆子地区呈东西向展布的基性岩脉为研究对象,在详细野外工作基础上,开展了岩石学、全岩地球化学、LA-I... 特提斯喜马拉雅带东段出露大规模早白垩世火成岩,其形成机制是否与东冈瓦纳大陆裂解有关备受学者们关注。本文以特提斯喜马拉雅带东段隆子地区呈东西向展布的基性岩脉为研究对象,在详细野外工作基础上,开展了岩石学、全岩地球化学、LA-ICP-MS锆石U-Pb定年及Sr-Nd同位素研究。结果显示隆子地区辉长岩成岩年龄为(136.9±1.4)Ma和(137.5±2.2)Ma,具有较高的FeO^(T)、TiO_(2)、P_(2)O_(5)含量,富集Nb、Ta、Zr等高场强元素,其地球化学特征介于OIB与E-MORB之间。Sr-Nd同位素显示高的(^(87)Sr/^(86)Sr)i值(0.7073~0.7097)和正的ε_(Nd)(t)值(3.78~4.82)。隆子地区辉长岩与Kerguelen地幔柱OIB型基性岩的全岩地球化学特征和Sr-Nd同位素组成相似,来源于Kerguelen地幔柱,受到了岩石圈地幔混染,是大陆裂谷背景下Kerguelen地幔柱早期活动(约136Ma)的产物。结合前人研究,本文认为是新特提斯洋板块北向俯冲引发了被动陆缘东冈瓦纳大陆的裂解,而Kerguelen地幔柱的出现加快了东冈瓦纳大陆的裂解。 展开更多
关键词 特提斯喜马拉雅带 早白垩世 SR-ND同位素 Kerguelen地幔柱 东冈瓦纳大陆裂解
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塔里木盆地中生代晚期‒新生代的区域应力场恢复及分析
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作者 吴尚欣 魏论研 +3 位作者 王睿哲 侯贵廷 李祥 夏金凯 《大地构造与成矿学》 北大核心 2026年第2期285-306,共22页
构造应力场研究在盆地演化、裂缝发育及断层封闭性分析中具有重要意义。近年来,盆地周缘大地构造演化与原型盆地研究取得了重要进展,地震和钻井数据为盆地建模及古应力场恢复提供了关键证据,从而为探讨盆地内部构造特征及其演化历史提... 构造应力场研究在盆地演化、裂缝发育及断层封闭性分析中具有重要意义。近年来,盆地周缘大地构造演化与原型盆地研究取得了重要进展,地震和钻井数据为盆地建模及古应力场恢复提供了关键证据,从而为探讨盆地内部构造特征及其演化历史提供应力场支持。本文基于弹性力学有限元数值模拟方法,对塔里木盆地中生代晚期‒新生代(即燕山期与喜山期)的构造应力场进行模拟分析,以恢复这两个时期的区域应力场特征。结果表明,塔里木盆地燕山期应力场主要受拉萨地块拼贴的远程效应影响,其东南缘表现出显著的左旋压扭作用,水平张应力主要集中于库车坳陷与塔中北部地区,差应力高值区偏向东北部。喜山期由于帕米尔构造结向北推挤,塔里木盆地西南缘的压扭作用显著增强,最大主压应力方向与一级控盆断裂走向呈垂直或大角度相交,与盆地内新生代主要断裂体系的发育及几何展布特征相呼应。塔里木盆地这两期构造应力场的差异反映了中‒新生代时期盆地南北两侧挤压作用与东西两侧旋扭应力作用边界条件的不同,表明盆地内部应力场的演化与周缘大地构造作用密切相关。 展开更多
关键词 塔里木盆地 数值模拟 应力场 燕山期 喜山期
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利用剪切波分裂方法研究喜马拉雅造山带中段地震方位各向异性特征
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作者 李鹏飞 李伦 +2 位作者 廖杰 赵凌峰 付媛媛 《地学前缘》 北大核心 2026年第3期403-413,共11页
喜马拉雅造山带是印度板块与欧亚板块碰撞所形成的,是研究陆陆碰撞深部过程的理想区域。剪切波分裂是一种能够获取壳幔地震方位各向异性的有效方法,可用于探测岩石圈变形与地幔流动。然而,由于喜马拉雅造山带中段的宽频地震台站分布较... 喜马拉雅造山带是印度板块与欧亚板块碰撞所形成的,是研究陆陆碰撞深部过程的理想区域。剪切波分裂是一种能够获取壳幔地震方位各向异性的有效方法,可用于探测岩石圈变形与地幔流动。然而,由于喜马拉雅造山带中段的宽频地震台站分布较为稀疏,对该区域地震各向异性研究较少,对俯冲的印度板块下方的地幔物质流动方向与状态仍缺乏足够的认识。本研究基于在喜马拉雅造山带中段布设的三分量宽频地震台网(2015年5月—2016年6月)记录到的地震波形数据,计算了远震SK(K)S波的各向异性参数,共获得12个台站的44个SKS震相和13个SKKS震相结果。结果显示,喜马拉雅造山带中段尼泊尔地区慢波平均延迟时间为0.72 s,快波偏振方向呈近东西向,与喜马拉雅造山带走向基本平行。这与前人在东喜马拉雅造山带获取的结果较为相似。结合喜马拉雅造山带已有的剪切波分裂结果,本研究认为喜马拉雅造山带走向平行的方位各向异性特征可能指示印度板片下方近东西向地幔流的存在,该地幔流在协调印度板块的俯冲动力学过程中可能扮演着重要角色。 展开更多
关键词 剪切波分裂 喜马拉雅造山带 上地幔 地震各向异性 地幔流
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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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喜马拉雅东构造结早古生代片麻岩锆石U-Pb年龄、Hf同位素特征及其地质意义
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作者 刘佳俊 王冬兵 +2 位作者 曾纪培 赵达臣 罗亮 《沉积与特提斯地质》 北大核心 2026年第1期155-168,共14页
高分异花岗岩与稀有金属成矿之间关系密切,喜马拉雅新生代花岗岩与喜马拉雅早古生代花岗岩同属高分异类型。同时喜马拉雅新生代花岗岩中的淡色花岗岩已被证实具有稀有金属成矿的潜力,关于喜马拉雅早古生代花岗岩是否有相同的潜力,还需... 高分异花岗岩与稀有金属成矿之间关系密切,喜马拉雅新生代花岗岩与喜马拉雅早古生代花岗岩同属高分异类型。同时喜马拉雅新生代花岗岩中的淡色花岗岩已被证实具有稀有金属成矿的潜力,关于喜马拉雅早古生代花岗岩是否有相同的潜力,还需进一步研究。本次在东构造结中识别出一套眼球状片麻岩,对其进行岩石地球化学、LA-ICP-MS锆石U-Pb定年及Hf同位素分析,结果显示,该套眼球状片麻岩原岩为高钾钙碱性过铝质花岗岩,样品具有高的SiO2(72.4%~75.18%)、Na_(2)O(2.72%~2.92%)含量和K_(2)O值(5.15%~5.72%),高的Na_(2)O/K_(2)O(0.52~0.53)和A/CNK比值(>1.1)。岩石地球化学特征表明其经历了较强的分异作用,是S型花岗岩。获得的锆石U-Pb年龄为(486±2)Ma,其Th/U比均大于0.1,代表了眼球状片麻岩原岩的结晶时间。εHf(t)值介于-12.5~-8.4,具有典型的壳源成因特点,Hf同位素的二阶段模式年龄TDM C介于2.20~1.99 Ga。综合野外地质和地球化学特征,本文认为喜马拉雅地块在早古生代发生了强烈的地壳重熔,南迦巴瓦眼球状片麻岩的原岩——高钾钙碱性花岗岩可能是在其影响下形成的,该套岩石与喜马拉雅早古生代岩浆岩具有良好的对应关系,可能是在同期喜马拉雅早古生代造山事件中形成。二者都是地壳熔融形成的产物,并且经历过较强的分异作用,具有相当有利于稀有金属成矿的条件。 展开更多
关键词 眼球状片麻岩 早古生代岩浆岩 结晶分异作用 东构造结
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喜马拉雅隆升历史对印藏碰撞模式的动力学制约
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作者 林丕旺 皇甫鹏鹏 李忠海 《大地构造与成矿学》 北大核心 2026年第2期325-343,共19页
青藏高原的形成与演化受印度板块与亚洲板块碰撞的控制,然而该碰撞系统的构造格架长期以来存在激烈争议。针对碰撞模式,目前存在三种观点:大印度大陆模式、洋内岛弧模式和大印度洋盆模式。为此,本文基于大尺度地球动力学数值模拟方法,... 青藏高原的形成与演化受印度板块与亚洲板块碰撞的控制,然而该碰撞系统的构造格架长期以来存在激烈争议。针对碰撞模式,目前存在三种观点:大印度大陆模式、洋内岛弧模式和大印度洋盆模式。为此,本文基于大尺度地球动力学数值模拟方法,构建上述三类不同构造格架下的印藏碰撞动力学模型。通过将模型结果与喜马拉雅‒青藏高原区域的实际观测资料进行系统对比分析,揭示在喜马拉雅地貌演化和青藏高原壳幔结构方面,大印度大陆模型均优于另外两类模型。本研究阐明喜马拉雅隆升时间显著滞后于印藏初始碰撞的动力学机制:在碰撞早期,大陆汇聚量首先被流变强度较低的青藏岩石圈吸收,导致青藏高原逐步隆升和扩展,而喜马拉雅地区的构造变形较弱,未出现明显的地形隆升;当高原主体完成隆升后,印度大陆岩石圈才开始俯冲至青藏岩石圈之下,伴随着俯冲过程中印度大陆上地壳物质的剥离并留存在地表形成造山楔,最终引发喜马拉雅的剧烈隆升。 展开更多
关键词 印藏碰撞 碰撞模式 数值模拟 青藏高原 喜马拉雅隆升
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Liupan Mountain National Nature Reserve
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《ChinAfrica》 2026年第3期62-63,共2页
Located in southern Ningxia Hui Autonomous Region,northwest China,the Liupan Mountain National Nature Reserve covers a total area of 26,783.64 hectares.Established in 1982 and upgraded to national status in 1988,it pr... Located in southern Ningxia Hui Autonomous Region,northwest China,the Liupan Mountain National Nature Reserve covers a total area of 26,783.64 hectares.Established in 1982 and upgraded to national status in 1988,it protects a vital temperate mountainous forest ecosystem on the Loess Plateau.The reserve is centred around the Liupan Mountain range,one of China’s youngest mountain chains,formed by Himalayan tectonic movements. 展开更多
关键词 National Nature Reserve Loess Plateau Northwest China Southern Ningxia Hui Autonomous Region temperate mountainous forest nature reserve himalayan tectonic movements Liupan Mountain
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2015年M_(W)7.8尼泊尔地震同震与震后应力调整对喜马拉雅地区地震活动性的影响
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作者 王凯 王志浩 +1 位作者 许炜 胡岩 《地球物理学报》 北大核心 2026年第4期1559-1568,共10页
2015年M_(W)7.8尼泊尔地震显著改变了喜马拉雅地区的地震活动性,表明该地震同震与震后应力调整可能对本地区地震触发具有一定影响.观测表明,尼泊尔地震后,破裂区附近的地震活动在2015年地震后到2017年间显著增强,而空间距离相对较远的2... 2015年M_(W)7.8尼泊尔地震显著改变了喜马拉雅地区的地震活动性,表明该地震同震与震后应力调整可能对本地区地震触发具有一定影响.观测表明,尼泊尔地震后,破裂区附近的地震活动在2015年地震后到2017年间显著增强,而空间距离相对较远的2025年M_(W)7.1定日地震区域在震后10年内的地震活动性亦较震前明显提升,表明震后应力调整可能起到关键作用.本研究基于长期GNSS观测数据约束的区域三维黏弹性有限元模型,系统分析了同震破裂、震后余滑及下地壳、上地幔的黏弹性松弛对区域应力场的时空演化特征的影响.结果表明,同震事件在主喜马拉雅逆冲断层(MHT)上引起了高达15 MPa的同震库仑应力扰动,而震后过程(如余滑和黏弹性松弛)则贡献了长期应力调整,在MHT震后余滑区域引起了可达3.7 MPa的10年累积的最大库仑应力降低.研究结果进一步揭示了震后应力调整对喜马拉雅活动断层地震危险性的影响,发现破裂区上下倾位置的主要断层均受到不同程度的应力加载,具有潜在的地震危险性.例如,此次尼泊尔地震和其7.3级余震对2025年M_(W)7.1定日地震的同震触发贡献了近18 kPa的库仑应力积累,并在震后持续缓慢增加,这显示了该尼泊尔地震对其后续邻近区域地震活动具有一定的促进作用.本研究为理解喜马拉雅地区的构造动力学及地震危险性评估提供了重要依据,同时强调了震后应力调整在地震周期中的重要作用. 展开更多
关键词 2015年M_(W)7.8尼泊尔地震 喜马拉雅造山带 库仑应力 震后过程 2025年M_(W)7.1定日地震
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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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