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Geomorphological responses of rivers to active tectonics along the Siwalik Hills,Midwestern Nepalese Himalaya

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Journal of Mountain Science 2021年第5期18卷 1268-1294页

作者： Indu BHATTARAI Nahid D.GANI Liang XUE Department of Earth Environmentaland Atmospheric SciencesWestern Kentucky UniversityBowling GreenKentucky 42101USA Earth and Environmental Sciences Syracuse UniversitySyracuseNew York 13244USA

The Nepalese Himalaya is well known for ongoing collisional tectonics,witnessed by major historical and recent *** Siwalik Hills in Midwestern Nepalese Himalaya are bounded by eastwest trending Main Frontal Thrust(MFT)to the south and the Main Boundary Thrust(MBT)to the *** area is dissected by numerous southwest to south-flowing bedrock *** study investigates geomorphic metrics of these rivers to unravel landscape evolution and active tectonics of the Siwalik *** Elevation Model(DEM)analysis was conducted to extract structural lineaments and longitudinal river profile and their metrics(knickpoints,Normalized Steepness Index(ksn),concavity index,and chi integral)using steam powerlaw *** of the lineaments trend eastwest like *** profiles exhibit convex to double-concave shapes with upstream-propagating tectonic knickpoints that separate upstream and downstream reaches,indicating different phases of river *** spatial distribution of ksn shows high values along with low concavity values at the eastern part of the study area,reflecting disequilibrium conditions that are likely responding to a high uplift *** integral distribution shows a variation in drainage divide migration between the eastern and western parts of the study *** study suggests that the rivers in the Siwalik Hills are undergoing active incision likely related to the ongoing uplift and active deformation associated with the Himalayan *** above findings can bring fresh perspectives to comprehend the neotectonic deformation and lateral variability along the Siwalik Hills landscapes within the Himalaya.

关键词： Longitudinal river profiles Siwalik Hills Nepalese Himalaya active tectonics

Geomorphic signatures and active tectonics in western Saurashtra,Gujarat,India

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Geodesy and Geodynamics 2024年第1期15卷 82-99页

作者： Bikramaditya Mondal Mery Biswas Soumyajit Mukherjee Mohamedharoon A.Shaikh Department of Earth Sciences Indian Institute of Technology BombayMumbai 400076MaharashtraIndia Department of Geography Presidency UniversityKolkata 700073West BengalIndia

active tectonics in an area includes ongoing or recent geologic *** paper investigates the tectonic influence on the subsidence,uplift and tilt of western Saurashtra through morphotectonic analysis of ten watersheds along with characteristics of relief and drainage *** 7-9 to the north(N)are tectonically active,which can be linked with the North Kathiawar Fault System(NKFS)and followed by watersheds 6,10,1,4 and ***-length gradient index and sinuosity index indicate the effect of tectonic events along the master streams in watersheds *** R^(2)values of the linear curve fit for watershed 7 indicate its master stream is much more tectonically active than the *** R^(2)curve fitting model and earthquake magnitude/depth analysis confirm the region to be *** reactivation of the NKFS most likely led to the vertical movement of western Saurashtra.

关键词： active tectonics Geomorphology Western Saurashtra Archeology North kathiawar fault system

Geomorphic signatures of active tectonics in Subansiri River Basin, eastern Himalayas

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Journal of Mountain Science 2020年第6期17卷 1523-1540页

作者： Diganta KUMAR Bhagawat Pran DUARAH Department of Geological Sciences Gauhati UniversityGuwahatiAssam-781014India

The Subansiri,a major tributary of the Brahmaputra with its catchment area(35763 km^2)spreading almost entirely in the Eastern Himalayas across almost all the major and local tectonic features in the area witnesses large numbers of seismic *** tectonic indices like relief and slope,drainage pattern,longitudinal profile,valley profile,hypsometry,valley asymmetry factors and transverse topographic symmetry index,stream length gradient,valley floor-height ratio extracted from SRTM 3 arcsecond data prove that the evolving basin morphology has substantial contribution from the Himalayan *** data are incorporated in the study to establish the potentially active tectonic elements in the catchment *** study shows that the western part of the Subansiri River Basin is profoundly tilted towards north in the upper catchment and towards east in the lower and middle part of the *** predominant tectonic movements in the western part of the basin caused the tilting of the basin towards north in the upstream and towards east in the middle and lower parts.

关键词： Eastern Himalayas active tectonics Subansiri Geomorphometry SRTM DEM Seismicity

Relative active tectonics evaluation using geomorphic and drainage indices, in Dadra and Nagar Haveli, western India

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Geodesy and Geodynamics 2022年第3期13卷 219-229页

作者： Naveen Kumar Rakesh K.Dumka Kapil Mohan Sumer Chopra Institute of Seismological Research(ISR) RaysanGandhinagarGujaratIndia Department of Earth Science Gujarat UniversityNavrangpuraAhmedabad380009India

The present study area,Dadra and Nagar Haveli,contains several lineaments and traces of active *** various aspect of the geomo rphic analysis,i.e.,stream length(SL) gradient,hypsometric integral(HI),basin shape(BS),valley floor(VF),have been applied to evaluate the relative index of active tectonics(RIAT) of the Damanganga *** high and low zones of tectonic activity have been identified based on the geomorphic analysis of the *** evaluation of all indices,three classes,class IIhigh(1.3 ≤RIAT <1.5),class Ⅲ-moderate(1.5 ≤RIAT <1.8),and class Ⅳ-low(1.8 ≤RIAT),have been obtained to outline the degree/gradation of comparative tectonic activities in the study *** appraised outcome of the RIAT dispersal is also well reinforced by the geomorphic evidence in the *** collective outcomes of geomorphic evidence,such as stream deflection and analysis of lineament,deflection of streams,and geomorphic indices,conceal that the Damanganga watershed is affected by tectonic activity.

关键词： active tectonics Geomorphic indices Relative index of active tectonics(RIAT) Drainage indices

Implication of Surface Fractal Analysis to Evaluate the Relative Sensitivity of Topography to active tectonics,Zagros Mountains, Iran

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Journal of Mountain Science 2015年第1期12卷 177-185页

作者： Ali Faghih Ahmad Nourbakhsh Department of Earth Sciences College of Sciences Shiraz University

Fractal geometry is increasingly becoming a useful tool for modeling and quantifying the complex patterns of natural phenomena. The Earth's topography is one of these phenomena that have fractal characteristics. This paper investigates the relative sensitivity of topography to active tectonics using ASTER Global Digital Elevation Model. The covering divider method was used for direct extraction of surface fractal dimension(D surf) to estimate the roughness-surface of topography with aid of geographic information system(GIS)techniques. This evaluation let us highlight the role of the geomorphic and tectonic processes on the spatial variability of fractal properties of natural *** zones can be delineated using fractal dimension mapping in which variability of surface fractal dimension reflects the roughness of the landform surface and is a measure of topography texture. Obtained results showed this method can be a quick and easy way to assess the distribution of land surface deformation in different tectonic settings. The loose alluvial deposits and irregularities derived by tectonic activity have high fractal dimensions whereas the competent formations and higher wavelength folded surfaces have lower fractal *** to the obtained results, the Kazerun Fault Zone has a crucial role in the separation of the Zagros Mountain Ranges into the different lithological,geomorphological and structural zones.

关键词： Surface fractal analysis Topography active tectonics Kazerun Fault Zone Zagros Iran

Uniform Strike-Slip Rate along the Xianshuihe-Xiaojiang Fault System and Its Implications for active tectonics in Southeastern Tibet

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Acta Geologica Sinica(English Edition) 2006年第3期80卷 376-386页

作者： HE Honglin RAN Hongliu Yasutaka IKEDA Institute of Geology China Earthquake Administration Beijing 100029 China Department of Earth and Planetary Science University of Tokyo Tokyo 113-0033 Japan

Recent studies on the Xianshuihe-Xiaojiang fault system suggest that the Late Quaternary strike-slip rate is approximately uniform along the entire length of the fault zone, about 15±2 mm/a. This approximately uniform strike slip rate strongly supports the clockwise rotation model of the southeastern Tibetan crust. By approximating the geometry of the arc-shaped Xianshuihe-Xiaojiang fault system as a portion of a small circle on a spherical Earth, the 15±2 mm/a strike slip rate corresponds to clockwise rotation of the Southeastern Tibetan Block at the （5.2±0.7）×10^-7 deg/a angular velocity around the pole （21°N, 88°E） relative to the Northeast Tibetan Block. The approximately uniform strike slip rate along the Xianshuihe-Xiaojiang fault system also implies that the Longmeushan thrust zone is not active, or at least its activity has been very weak since the Late Quaternary. Moreover, the total offset along the Xiaushuihe-Xiaojiang fault system suggests that the lateral extrusion of the Southeastern Tibetan Block relative to Northeastern Tibetan Block is about 160 km and 200-240 km relative to the Tarim-North China block. This amount of lateral extrusion of the Tibetan crust should have accommodated about 13-24% convergence between India and Eurasia based on mass balance calculations. Assuming that the slip rate of 15±2 mm/a is constant throughout the entire history of the Xianshuihe-Xiaojiang fault system, 11±1.5 Ma is needed for the Xianshuihe-Xiaojiang fault system to attain the 160 km of total offset. This implies that left-slip faulting on the Xianshuihe-Xiaojiang fault system might start at 11±1.5 Ma.

关键词： Xianshuihe-Xiaojiang fault system southeastern Tibet strike-slip rate active tectonics

A Review on Researches of active tectonics—History,Progress and Suggestions

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Earthquake Research in China 2009年第1期23卷 1-27页

作者： Deng Qidong Wen Xueze Institute of Geology China Earthquake Administration Beijing 100029 China Earthquake Administration of Sichuan Province Chengdu 610041 China

This paper reviews the history and progress of research on active tectonics in China and *** giving a brief introduction on the history of active tectonic research in China and other countries,the paper sums up the process and development of quantitative investigation of active tectonics since the *** focus is on the main efforts and progress made in China on certain aspects of research,such as basic surveys and applied investigation of active tectonics,the study of theories related to regional active tectonics and their kinematics and geodynamics,surveys on coupling relations between deep and shallow structures,active fault surveys and prospecting and seismic hazard assessment in urban areas,as well as the efforts made using Quaternary ***,the paper looks back on Chinese quantitative investigation of active tectonics in China and sums up cognitions derived from studies on the determination of several basic and measurable parameters of active *** parameters include the length of fault and fault segmentation,coseismic slip and cumulative slip,fault slip rate,the sequence of paleoearthquake events and the time elapsed since the most recent *** the same time,efforts and progress made in China on assessing the long-term seismic potential for active faults and evaluating the risk from potential active fault movement have been reviewed by summarizing research on developing theories,models,methods and the application of time-dependent seismic potential to probabilistic assessment,magnitude estimation for potential earthquakes on active faults,and the forecast of potential risk caused by active fault ***,in consideration of the realities and problems in the research of active tectonics in China,the authors put forward several suggestions for issues worthy of more attention for further investigation in the future.

关键词： active tectonics History and progress of research Quantitative investigation Problems and suggestions

An Introduction to the Latest-generation Spatial Database of active tectonics of China

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Earthquake Research in China 2009年第2期23卷 237-243页

作者： Qu Chunyan Deng Qidong State Key Laboratory of Earthquake Dynamics Institute of Geology CEA Beijing 100029 China

Based on ArcGIS and MapInfo software, we digitized the active tectonics map (1:4,000,000) of China, which was compiled and revised by academician Deng Qidong, and built the spatial database of active tectonics of China. The database integrates rich active tectonic data, such as a catalogue of earthquakes with magnitude above 6.0, active faults, Quaternary basins, active folds and their associated attribute parameters, and implements scientific and effective management to this data. At the same time, the spatial database joins the spatial map data and the associated attribute data together, which implements the data query between spatial properties and attribute parameters and also makes it possible to perform spatial analysis with different data layers. These provide much convenience for earthquake study and allows engineering construction institutions to use this data in practical applications.

关键词： active tectonics Spatial database GIS

Geospatial analysis of neotectonics in the Jebel Gustar Mountain,northeastern Algeria

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Journal of Mountain Science 2025年第2期22卷 391-403页

作者： TAIB Hassan HADJI Riheb ZIGHMI Karim HAMED Younes GENTILUCCI Matteo BEDRI Khaoula Department of Geological Sciences Faculty of Earth SciencesGeography and Regional PlanningUniversitéFrères Mentouri-Constantine 1 BP325 Route d’Ain El Bey 25017ConstantineAlgeria Laboratory of Applied Research in Engineering Geology GeotechnicsWater Sciences and EnvironmentFerhat Abbas UniversitySetif 19137Algeria Department of Earth Sciences Institute of Architecture and Earth SciencesFerhat Abbas UniversitySetif 19137Algeria International Association of Water Resources in the Southern Mediterranean Basin Gafsa 2112Tunisia Department of Earth Sciences Faculty of Sciencesuniversity of GafsaCampus Universitaire Sidi Ahmed Zarroug–2112GafsaTunisia School of Science and Technology Geology DivisionUniversity of CamerinoVia Gentile III da Varano762032 Camerino MCItaly Mining Engineering Laboratory National Polytechnic School of Algiers10 Rue des Frères OUDEKEl Harrach 16200 AlgiersAlgeria

This research investigates dynamic earth processes within the South Setifian allochthonous ensemble,providing insights into landscape evolution and seismotectonic activity within the Tellian mountain *** on the Jebel Gustar and Kef Lahmar area,which includes 14 sub-basins,this research uses a DEM-based technique to assess Holocene activities,lineament characteristics,and stream *** geomorphic indices are used to assess relative active tectonics:the stream lengthgradient index(SL),drainage basin asymmetry(AF),valley-floor width to valley height ratio(VF),drainage basin shape(BS),and mountain front sinuosity(SMF).A weighted overlay of these five indices produces the Index of Relative active tectonics(IRAT)*** findings reveal significant neotectonic activity in the study area,supported by profound basement *** research highlights the morpho-structural processes and neotectonics activity in the Jebel Gustar,providing a framework for investigating the evolution of this ***,it enhances comprehension of the interactions between the alpine range's internal zones in Eastern Algeria and the Atlasic *** study proposes a systematic approach to evaluate the tectonic and geomorphological dynamics of the South Setif region.

关键词： active tectonics Crustal deformation Holocene activities Geomorphic indices Neotectonic dynamics