Geomorphic Changes Related to Anthropogenic Interference Along the Ganga River From Rishikesh to Haridwar, Uttarakhand, India

Author(s):  
Manish Pandey ◽  
Aman Arora ◽  
Rajesh Kumar ◽  
Vijendra Kumar Pandey ◽  
Akshay Kumar

The authors, in this study, have quantified the changes in the geomorphic activity of the Ganga River between Rishikesh and Haridwar by using Survey of India (SOI) 1:5000 scale topographic sheets, satellite data, digital elevation model (DEM), and hydrological data from published resources. They have also correlated the change in settlement area in Haridwar and Rishikesh and connected it to the changing geomorphic features in the downstream reach of the Tehri dam site. The study finds that the change in geomorphology of the river in the studied reach of the Ganga River is attributable to reduced water and sediment supply. The study area being in the active tectonic zone, bound between MCT in the north and HFT in the south, may have experienced offsetting of the reduction in sediment supply by dam in the post dam era (after 2006) due to massive earthquakes delivering sediment directly delivered to streams through enhanced landslide and other mass wasting processes.

2011 ◽  
Vol 5 (1) ◽  
pp. 401-430 ◽  
Author(s):  
C. Mayer ◽  
A. Lambrecht ◽  
W. Hagg ◽  
Y. Narozhny

Abstract. Glaciers are important water storages on a seasonal and long-term time scale. Where high mountains are surrounded by arid lowlands, glacier runoff is an important source of water during the growing season. This situation can be found in the Altay mountains in Southern Siberia, where the recent glacierization of >700 km2 is subject to continuous mass loss, even though the shrinking is comparably slow. The glacier retreat is accompanied by an extension of supra-glacial moraine, which itself strongly influences ablation rates. To quantify these effects, the spatial evolution of debris cover since 1952 was analysed for three glaciers in the North Chuya Ridge using satellite and airborne imagery. In summer 2007, an ablation experiment was carried out on debris covered parts of Maliy Aktru glacier. Thermistors in different depths within the moraine provided data to calculate thermal resistance of the debris. A set of ablation stakes was installed at locations with differing debris thickness and observed regularly throughout the entire melt season. Air temperature from an AWS was used to calculate degree day factors in dependence of the debris thickness. To take into account the shading effect of surrounding walls and peaks, the potential solar radiation and its evolution throughout the summer was determined from a digital elevation model. This allows us to extrapolate our measurements from Maliy Aktru to the other two glaciers of the Aktru basin and to estimate basin melt rates. In addition accumulated ice melt was derived for 12 glaciers in the North Chuya Range. Changes in summer runoff from the 1960s are compared to the results from our melt model and the evolution of debris cover is analysed in respect to the melt activity.


2006 ◽  
Vol 21 (4) ◽  
pp. 195-202
Author(s):  
Marvin R. Pyles ◽  
Mari Kramer

Abstract An aerial photo-based inventory of landslides on recently harvested and reforested land after a significant landslide-producing storm in February 1996, was compared with a digital elevation model-based assessment of slope stability (shallow landsliding stability model [SHALSTAB]) for Confederated Tribes of Siletz Indians (CTSI) and surrounding forestland. The SHALSTAB predictions of landslide locations did not correlate well with the locations of observed landslides. Eighty-nine percent of the landslides on the more stable landform in the southern portion of the CTSI ownership occurred on land that SHALSTAB indicated to be at a low risk of landsliding. Seventy-two percent of the landslides on the less stable landform to the north occurred on land that SHALSTAB indicated to be at a low risk of landsliding. Conversely, only 11 and 28%, respectively, of the observed landslides occurred on lands predicted to be “chronically unstable” or at “high risk” by SHALSTAB. This level of correct prediction of landsliding was judged to be unacceptable for SHALSTAB to be used for slope stability assessment as a part of forest management planning. West. J. Appl. For. 21(4):195–202.


2018 ◽  
Vol 17 (2) ◽  
pp. 65-80
Author(s):  
Eva Stopková

The paper summarizes the geodetic contribution for the Slovak team within the joint Polish-Slovak archaeological mission at Tell el-Retaba in Egypt. Surveying work at archaeological excavations is usually influenced by somewhat specific subject of study and extreme conditions, especially at the missions in the developing countries. The case study describes spatial data development according to the archaeological conventions in order to document spatial relationships between the objects in excavated trenches. The long-term sustainability of surveying work at the site has been ensured by detailed metadata recording. Except the trench mapping, Digital Elevation Model has been calculated for the study area and for the north-eastern part of the site, with promising preliminary results for further detection and modelling of archaeological structures. In general, topographic mapping together with modern technologies like Photogrammetry, Satellite Imagery, and Remote Sensing provide valuable data sources for spatial and statistical modelling of the sites; and the results offer a different perspective for the archaeological research.


Solid Earth ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 2047-2074
Author(s):  
Oleg Sizov ◽  
Anna Volvakh ◽  
Anatoly Molodkov ◽  
Andrey Vishnevskiy ◽  
Andrey Soromotin ◽  
...  

Abstract. Analysing the genesis of Quaternary sediments is important for understanding the glaciation history and development of marine sediments in the northern part of Western Siberia. The problem is relevant since there is no consistent concept of the Quaternary sediment genesis in the north of Western Siberia. The formation of sediments is associated with marine, glacial and interglacial sedimentation conditions. The research objective is to identify the persistent features characterising the conditions of sedimentation and relief formation using the Nadym River basin as an example. The best method for studying this problem is a comprehensive analysis of the lithological, chronostratigraphic, petrographic and geomorphological studies of the Quaternary sediment upper strata. This study provides data from the analysis of the basic characteristics of quartz grains at the site. The rounding and morphology of the quartz grains provide evidence of possible glacial processing of some of the site strata. A petrographic study of selected boulder samples was performed. Some of them, by the shape and presence of striation, can be attributed to ice basins. The first use of a detailed digital elevation model applied to the study area made it possible to identify specific relief forms that could very likely be created during glaciations. Based on the analysis, we propose to consider the vast lake alluvial plains in the Nadym River basin as periglacial regions. This idea lays the lithological framework for understanding the reasons for the formation of the modern landscape structure. The materials and descriptions provided are of interest to researchers of Quaternary sediments, topography, vegetation and soil cover, particularly researchers engaged in revising the history of the natural environment development in the north of Western Siberia.


Land ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 667
Author(s):  
Xun Yang ◽  
Fabian Becker ◽  
Daniel Knitter ◽  
Brigitta Schütt

Current landforms are the basis for understanding past geomorphodynamics and human activities. Based on multiple materials and methods, including geomorphometric analyses of a digital elevation model and visual interpretations of satellite images, different landscape units of the Bakırçay and Madra River catchments in the environs of ancient Pergamon are described. The area was mainly shaped by tectonics that formed a horst-and-graben structure; small Miocene horsts and NE-trending subgrabens in the Kozak and Yunt Dağı Mountains were separated by the NEE-trending Plio-Pleistocene Bergama Graben. The asymmetry in relief, drainage network, and sediment accumulation between the Kozak Mountains to the north and the Yunt Dağı Mountains to the south of the lower Bakırçay plain characterize the Pergamon Micro-Region. The regional relief characteristics, with wide flat basin and plateau areas, are suitable for agriculture. Complemented by its richness in natural resources, the Pergamon Micro-Region became a preferred settlement area, with evidence of human impact since the Hellenistic–Roman period at the latest. As a consequence of settlement activities, several landscape engineering measures were implemented simultaneously with a parallel change in morphodynamics.


Author(s):  
O. M. Kunah ◽  
O. S. Papka

<span>The role of geomorphological ecogeographical variables have been shown, which are received by means of the digital elevation model created on the basis of remote sensing data as markers of an ecological niche of weeds on an example common milkweed (</span><em>Asclepias syriaca</em><span> L.). The research range chooses territory which is in settlement Vovnjanka district (the Poltava region). The range has the linear sizes of 26 kilometres in a direction from the east on the west and 15 kilometres in a direction from the north on the south, the range total area makes 390 км</span><sup>2</sup><span>. As geomorphological variables the topographical wetness index, topographic position index, mass balance index, erosion LS-factor, direct and disseminated insolation, altitude above channel network, multiresolution valley bottom flatness, multiresolution ridge top flatness index, vector ruggedness measure have been considered. It is established, that on set of the geomorphological indicators received by means of digital model of a relief, it is possible to assert, that within a separate agricultural field a wide variety of microconditions which is caused by relief features is formed. Possibly, the variation of thermal and water modes, moisture redistribution, and also productivity mechanical processings of soil and efforts under the control of number of weeds make a background in which limits there is possible a moving of weed plants, including common milkweed.</span>


2021 ◽  
Author(s):  
Bahar Rezaeinahal ◽  
Mohsen PourKermani ◽  
Mehdy Zare ◽  
Maryam Dehbozorgi ◽  
Reza Nozaem

Abstract The northwest zone of Saveh city is located in the fault zone of the Indes, Koosh e Nosrat, Avaj and Aipak. Indes faults, Cox Nosrat, Avaj and Aipak are considered as the major faults of central Iran, which are also active in the Quaternary and the last movements of these faults are attributed to the present covenant, therefore, the estimation of morphometri in order to identify the effect of active tectonics on the tectonic evolution of drainage basins seems necessary. Therefore, in this study, six important morphotectonic indexes were analyzed; longitudinal gradient of the river, asymmetry of drainage basin, hypometric integral, Drainage basin shape,the ratio of the width of the floor to the height of the valley and forehead of the mountain is discussed.to create the basins on the studied area, Arc Hydro software (Arc GIS software) has been used based on data from a digital elevation model, Then, 6 morphotectonic indexes have been compiled and classified on each of the basins.Finally, according to which the region has been classified into 4 categories of high, medium and low tectonic activity the, Active Tectonic Index (IAT) has been calculated.According to the IAT index, 5% of the study area shows very high tectonic activity, 25% of the studied area has high tectonic activity, the average tectonic activity has 65% and about 5% of the tectonic activity are low. In this study, the highest level of tectonic activity is in the north-eastern part of the region. In most of the sectors, the level of activity is high and moderate, which is related to the activity of Koshk E Nosrat, Aipak, Avaj faults.


2001 ◽  
Vol 34 (1) ◽  
pp. 345 ◽  
Author(s):  
Z. TUTKUN ◽  
S. PAVLIDES

The Mw=7.4 Izmit (Kocaeli) earthquake of August 17, 1999 (Turkey) ruptured 100 km at least surface faults on land along the northwestern branch of the North Anatolian Fault Zone (NAFZ). Although the preexisting structures of NAFZ has been divided into segments, showing stepover and pull apart geometry, the earthquake ruptures are generally linear, E-W striking (N80°-100°), right-lateral. In small scale and on the recent sediments they show very typical strike-slip displacements (2 to 5m), pop-ups and pressure ridges (N 40- 70°), Ρ (N80°), R (N100-1100) and R' (~N350°) Riedel shears, extensional cracks (N115°-135°), restraining and releasing bends and small pull apart structures. In the epicentral area (Gölcük-Tepetarla) the seismic ruptures did not follow any known or previously mapped fault, but the morphology and the Digital Elevation Model (DEM) show typical and recognizable paleo-earthquake features. That is elongated valleys, shutter ridges, high angle slopes, scarplets, stream offset; while trenching tectonostratigraphy indicate palaeo sag-ponds (clayly deposits) and palaeo liquefaction (C14 dating-Holocene-historical deposits 200 to 11,000 yr. BP).


Author(s):  
J. K. Ogunmola ◽  
E. A. Ayolabi ◽  
S. B. Olobaniyi

The Upper Benue Trough is part of the Benue Trough of Nigeria and is comprised of three basins: the east–west trending Yola Basin (Yola Arm), the north–south trending Gongola Basin (Gongola Arm) and the northeast–southwest trending Lau Basin (Main Arm). This research is an ongoing research at understanding the structural framework of the Upper Benue Trough using several techniques including the use of Remote Sensing and GIS. Several digital image enhancement techniques such as general contrast stretching and edge enhancement were applied to the NigeriaSat-X and SPOT 5 image in ERDAS IMAGINE 9.2 after which structures were mapped out on-screen using ArcMap 10. The Digital Elevation Model (DEM) of the Trough was also used to enhance geomorphic features. The analysis carried out on the images revealed that lineaments are abundant in the Upper Benue Trough and they can be subdivided into four major trends, NE&ndash;SW, NW&ndash;SE, W&ndash;E and N&ndash;S in order of abundance and range in length from about 300 m to 26 km. Several faults were also mapped out within the Basin such as a sinistral fault around Bakoreji village in Bauchi, a dextral fault close to Kalmai town in Gombe and a dextral fault close to Wong in Taraba. It was discovered that some of the sites where minerals such as lead and zinc ores are being mined occur in the zones of high lineament density. This study shows the capability of the DEM, SPOT 5 and NigeriaSat-X images for lineament/structural interpretations.


2020 ◽  
Vol 70 (4) ◽  
pp. 145-154
Author(s):  
Caroline Schuldt ◽  
Jochen Schiewe ◽  
Johannes Kröger

AbstractThe future sea-level rise caused by climate change will lead to coastal regions being flooded and ecological and socio-economic systems being disrupted. This study examines the question of how the sea-level rise in Northern Germany can be simulated on a regional level and visualized as a media map. The simulation is based on the TanDEM-X digital elevation model, IDW interpolated current measurements of the sea level and the vertical land movement, as well as regional sea surface elevation projections for the year 2100. Two different climate scenarios were applied based on IPCC forecasts. Particular attention was paid to transforming elevation systems into orthometric heights. In addition, the uncertainties existing in the simulation of future developments were quantified and visualized. Depending on the applied scenario, an area between 1061 and 9004 km2 will be inundated. Accordingly, the affected population varies between 5477 and 626,880 people. The calculation of the inundated areas reveals serious differences; between the various climate scenarios, as well as between the North and Baltic coasts, but above all between the assumption of a stable coastal protection on the one hand and a dike breach on the other. Based on the requirements of journalistic cartography and the specific requirements of the German broadcasting company Norddeutscher Rundfunk (NDR), static maps were developed, which will be shown as a sequence starting with the least and ending with the most severe possible impact.


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